Rotax Oil Injection: Friend or Foe?

[Trez]

This might be of use to some...........

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http://www.aero-news.net/columns/sportplane.cfm?ContentBlockID=1088b2c0-0dff-42ba-93f8-cf3fc588062c&Dynamic=1


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[Doug Riley]

OTOH:

K.I.S.S.

The injection system is a veritable cuckoo clock of little parts. I am grumpy about trusting my well-being to a small plastic gear.

[Earthboundmisft]

Ditto, this hoss done been rode to death....:bored:

[Passin' Thru]

ditto, this hoss done been rode to death....:bored:
........................... .

[Trez]

Ditto, this hoss done been rode to death....:bored:

Sounds like "pull up the ladder"? ............ :rip:

[DennisFetters]

You should never fly a Rotax without an oil injector. Its like riding a motorcycle without a helmet, just stupid. It is one of the best improvements they came up with for those engines. I have posted on the points here before, so for those that want the facts, just search for what I wrote.

[Friendly]

OTOH:

K.I.S.S.

The injection system is a veritable cuckoo clock of little parts. I am grumpy about trusting my well-being to a small plastic gear.

Doug,
this is funny coming from you. I respect your decision. I just always consider you on the advancing edge of things. I wonder what the statistics say about pumps vs premix

[C. Beaty]

Mark, there is absolutely no advantage to running oil injection with a fixed pitch prop where load and engine rpm closely correlate.

There is an advantage to oil injection when running a constant speed prop or powering a helicopter.

With the engine running at constant rpm and power controlled by throttle, there may be too much oil at full throttle and too little oil at partial power setting, the engine always running at say 6,000 rpm.

[Earthboundmisft]

Thank you Chuck.:hail:

[DennisFetters]

Mark, there is absolutely no advantage to running oil injection with a fixed pitch prop where load and engine rpm closely correlate.

There is an advantage to oil injection when running a constant speed prop or powering a helicopter.

With the engine running at constant rpm and power controlled by throttle, there may be too much oil at full throttle and too little oil at partial power setting, the engine always running at say 6,000 rpm.

What chuck said about a helicopter is true, but about being no advantage in a fixed pitch application is just absolutely wrong. I suggest that if you are going to listed to advice, at least make sure the person has gone to the authorized Rotax overhaul and maintenance school.

Here is just some common since information I posted here some time ago;

"""Always use the oil injector. Never allow yourself to be talked into taking it off, because "it's just something else that can fail" reason. Oil viscosity is what protects your engine. Mixing with gas will lower the viscosity and give much less protection and reduced engine life. Oil injected into the ports brakes up into micro-beads of oil, but each still have their high viscosity for protection.

The only two things that wear out the Rotax engine that has been properly installed and cooled, is poor lubrication and carbon buildup.

When Rotax first offered oil injection, there were a few problems. It was not the oil injector failing, but contamination that was somehow getting in the oil that was causing the failure. Rotax made it mandatory to use a special filter between the tank and injector, and all the problems went away, and that was years ago.

There is no good reason not to use the oil injector, and there are many good reasons to use an oil injector.

1. Better lubrication from higher viscosity oil droplets.

2. Uses much less oil then mixing, reducing pollution, carbon buildup and smoke.

3. Oil injected droplets tend not to burn as much, or in the bad way that mixed oil does. Mixed oil burns dry and causes buildup, while injected droplets tend to stay wet and burn in the exhaust system, clogging rings to a much lesser degree.

4. You can take much longer trips using oil injection, because you don't need to add oil for up to 10 fill-ups, while you need to mix every time you fill-up.

5. You don't need to carry oil with you on cross country flights when you fill-up at other locations, mixing oil you do.

6. You can go up to 10 fill-ups before having to remember to add oil when you have an oil injector. You have to remember every time when mixing.

7. I have had only 2 Rotax engine failures out of the thousands of hours I have flown gyros. Both were due to not mixing the oil with the fuel. I have never had a single engine failure since I started using oil injection.

Why would anyone not use oil injection?""

[Flying_Lab_Rat]

I could argue on both sides, but as oil injection has been around a while, I would have one question to ask...Has anyone seen a failure in the oil injection system?

[mark treidel]

I ran a blue head 582 (with oil injection) on my trike for 500+ hours before selling it.
The only thing I had to do was normal decarbonization. Never had an issue or failure in all that time. When We pulled the exhaust (prior to sale) to look inside, the pistons still had cross hatching readily visible and the rings were free. The tops of the pistons were shiney w/o carbon. My experience....It (injection system) is improved now to the point where it is worry free. The only crucial requirements is to make sure the rotary valve reservoir is full and that the hash marks are lined up on the delivery adjustment. Not a bad idea to change the filter at annual either.
By the way, all these hours were put on between 2004-2009. Injection has been around for a long time now and is fully recommended by rotax. Gotta agree with D.F. on this one.

[CLS447]

I was going to start another new thread on this subject, but instead I am just going to add on to this one.

I have oil injection on my 503 & so far I love it. I started thinking about the weaknesses of the system.

Starting at the pump, I would like to discuss how it all works & what could or has failed with these systems.

What actually drives the pump shaft ?

Please....let's not get into a debate about removing it !

[Brent Drake]

The oil injection quit on the Rotax at Mentone this year. Which caused a force landing. I would always mix.

[CLS447]

What exactly quit ?

Did the motor sieze ?

[JEFF TIPTON]

The Rotax oil oil pump is simple in design and although failures are rare they could happen.

The pump is mounted on the end of the motor opposite the output shaft and is typically attached with four screws. A plastic shaft connects the pump to the engine crankshaft. This shaft rotates with the engine RPM. The faster the engine turns the more oil the pump will provide.

A second part of the pump is the regulator. This part is controlled by the lever at the pump. Its purpose is restrict the oil flow at part throttle positions. There is a mark of the pump and the lever arm that must be set after the carburetor slides have been adjusted. Depending on your pump the marks will line up with the throttle at idle or the other style will line up with throttle full open.


Weak points might be the plastic input shaft. With age, I would suspect it would become brittle.
Connections at the oil pump or the injection point being loose.
Congealed oil not pumping. I think I read that mixing synthetic with petroleum based oils will cause this.


I have never seen a recommended replacement time for the input shaft.

And I am not sure of the best way to purge the oil from the system when going from the synthetic to the petroleum based or the other way around.

[cburg]

What exactly quit ?

Did the motor sieze ?

http://www.rotaryforum.com/forum/showthread.php?t=35036&highlight=glen

http://www.rotaryforum.com/forum/showthread.php?t=34814&highlight=rotax+rick&page=3

[Glenn_K]

Mine was the one that quit at Mentone. Rotax 670 with 13.5 hours on it. I'm not sure of the specifics of the failure, but maybe Rick will chime in here with those particulars. He only told me that the oil injection system failed and the resulting damage to the PTO side of the engine was total. All the bearings were destroyed, the rod punched through the bottom of the case and cracked the case all the way around. Debris found its way into the chamber and damaged the piston and the cylinder. I had to put it down in a bean field about 5 miles from the Mentone airport. He sent the replacement engine with the oil injection removed and I'm premixing from here on out as per his instructions.

[gyronutjoe]

I believe in oil injection. In the 15+ years working on 2 stroke scooters I have had to replace only 2 engines because of oil pump failure and even those gave warnings first. The only other oil related failures were forgetting to fill the oil tank!!! I love the way Aprilia does it on their 2 stroke scooters. 2 separate injection systems, oil into the crankcase and fuel directly into the top of the piston chamber. The oil is not diluted by fuel and this way they use much less oil. Works better than anything else I've ever seen.

[CLS447]

Jeff, thanks.....well written. So the regulator cuts back on the flow at idle ? Then after that ,RPM dictates the exact amount ? There is no metering device ?

so when I am at 6000 rpms the oil pump is the same, or does it use a gear reduction ?

The plastic input shaft might be a concern, but I guess Rotax doesn't think so.

Next are the two little banjo fittings.....what is the deal with them (check valves) ?

[CLS447]

This might be of use to some...........

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http://www.aero-news.net/columns/sportplane.cfm?ContentBlockID=1088b2c0-0dff-42ba-93f8-cf3fc588062c&Dynamic=1


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What was this ??

[scottessex]

If I am not mistaken, Bombardier, the parent company of BRP-Rotax,
makes the engines for Aprilla.....Rotax does not make the oil pump, the oil pump is made by Mikuni.
Mikuni would not allow Rotax to use its carbs on aircraft engines because of liability issues. same with the ignition, that is why they went with Ducatti,

But Mikuni allowed them to use the oil pump, so apparently Mikuni thought it was reliable enough that they would allow rotax to use it.

Better argument---Ginger or Maryann? :)

[Penguin]

Better argument---Ginger or Maryann? :)

Mrs. Howell.
Damn - I'm old!

[JEFF TIPTON]

The oil pump lever controls the oil flow at all RPM's. The oil pump will supply more oil than the engine needs and the lever restricts the oil.

Imagine a shaft with a hole drilled across it. Now imagine the shaft goes into a hole that also has a hole drilled across it and the shaft hole will line up with. We can either rotate the shaft, or move the shaft in and out to change the relationship of the two holes. With the two holes lined up, we would have maximum flow, and as we move the holes out of alignment we can restrict the flow based on how much offset between the holes.

There can be times when the lever is restricting the oil flow to much such as engine at idle and the propeller is windmilling during a steep decent. I could also see this happening on an engine using premix.

The banjo fittings. check valves, are important. The oil tank is mounted above the oil pump. This helps to ensure no air enters the oil lines during operation. The check valves are spring loaded balls that will stop the flow of oil when the engine is not running. Without these check valves the oil would drain from the oil tank into the engine or onto the ground depending on the angle of the intakes.

[Rotax Rick]

Oil; injection is UNRELIABLE . PERIOD We completed test, Test 1 = 56 to 1 ratio, Test 2 = 91 to 1 ratio, Test 3 = 81 to 1 ratio Oil injection was developed to make 2 strokes seem like a 4 stroke engine of easy use. NOT FOR RELIABILTY !!!!!!!!!!!!!!

[Ronnie328]

Oil; injection is UNRELIABLE . PERIOD We completed test, Test 1 = 56 to 1 ratio, Test 2 = 91 to 1 ratio, Test 3 = 81 to 1 ratio Oil injection was developed to make 2 strokes seem like a 4 stroke engine of easy use. NOT FOR RELIABILTY !!!!!!!!!!!!!!I don't have any opinion on Oil injection or premixing, but these tests do have me curious. Do you have any reference numbers to go with these ratios? Engine RPMs, Temperatures recorded, or even some apparent wear? All with comparisons to premix?

One day i'll be in a gyro of my own, and i'd love to have some insight to things like this in performance settings before i choose engines and operating procedures.


**On a side note, how much easier is it to use Oil Injection over premixing? Just don't have to shake to mix it up, right? lol

[okaneco1]

Do you know what the dots on the oil pump level are used to reference? If you look at the picture in thread #24 you can see the dots. My understanding is that you can use safety wire to tie the pump lever in the up position on the dot to the the line on the pump and get 50:1 oil ratio and not connect the cable to the throttle.

[CLS447]

If I am not mistaken, Bombardier, the parent company of BRP-Rotax,
makes the engines for Aprilla.....Rotax does not make the oil pump, the oil pump is made by Mikuni.
Mikuni would not allow Rotax to use its carbs on aircraft engines because of liability issues. same with the ignition, that is why they went with Ducatti,

But Mikuni allowed them to use the oil pump, so apparently Mikuni thought it was reliable enough that they would allow rotax to use it.

Better argument---Ginger or Maryann? :)

Scott, What liability ? Has Rotax or Mikuni ever been sued successfully ?

What argument ?

Maryann, definitely ! ( I rethought this one.....both )

[CLS447]

Oil; injection is UNRELIABLE . PERIOD We completed test, Test 1 = 56 to 1 ratio, Test 2 = 91 to 1 ratio, Test 3 = 81 to 1 ratio Oil injection was developed to make 2 strokes seem like a 4 stroke engine of easy use. NOT FOR RELIABILTY !!!!!!!!!!!!!!

Can you explain this in better detail ? Please ?

This raised more questions than answers....

[GyroRon]

Chris, you know that your not going to get rid of your oil injection, so why discuss it! Just for something to talk about?

Rotax Rick is right, oil injection is there to make it easier to use the engine..... just put gas where gas goes, add oil to the tank as needed. No need to worry about ratios or carrying extra oil on typical short cross country flights, etc...

Sure when everything works as it should, oil injection works fine. When it doesn't, your engine is fried. Simple as that.

So you have to weight the pros verses the cons.

For me, I just prefer the engine to be less complicated, less stuff to go wrong, less weight on my machine, less bulk.

[CLS447]

The banjo fittings. check valves, are important. The oil tank is mounted above the oil pump. This helps to ensure no air enters the oil lines during operation. The check valves are spring loaded balls that will stop the flow of oil when the engine is not running. Without these check valves the oil would drain from the oil tank into the engine or onto the ground depending on the angle of the intakes.

Depending on the angle of the intake ? While installing my new 503, I struggled with the answer to this question.....Which way do the intakes go ?

I finally settled on this answer.....the oil is always injected into the bottom of the intakes.

This tilts the intake side of the carbs downwards. Do you agree with this ?

Next question.....so the spring check banjos are another possible point of failure ?

What amount of pressure does the oil pump generate ?

[PW_Plack]

Scott, What liability ? Has Rotax or Mikuni ever been sued successfully ?

A lawsuit doesn't have to be "successful" to be expensive and damaging for a company. Just going to court or being forced to settle could put many companies in financial trouble.

[PW_Plack]

If Rotax ever stops milking the old technology of the 582 and introduces aviation versions of its direct-injection two-strokes, pre-mix won't be an option anymore. Hopefully the newer designs will meet everyone's comfort level for reliability.

[JEFF TIPTON]

The angle I was referring to was referencing the intake. If the engine were stored in a manner that the area where the air filter is mounted is lower than the point where the oil enters the intake, the oil would probably only leak onto the ground. Otherwise, it would collect in the crankcase. Enough oil collected in the crankcase during running will probably blow the crankshaft seals or the case seals.

Any time we add another part to system it is another point of potential failure.

I have no idea as to the pressure of the pump. I would imagine not much with the small size of the pump gear.

[Brent Drake]

I could be wrong here but, I'm thinking I read somewhere that our government was going to ban the production of 2 stroke engines in 2016. This is why most small engine people are starting to make 4 stroke blowers and weed trimmers.
Could the Rotax be on the way out in America unless they start producing small 4 stokes?

[scottessex]

You will just be forced to buy a 912...... or quit flying..

[MrGrey]

Never saw an engine with pre-mix get starved of oil, only injection... just sayin.

[WHY]

Very simple, with oil injection Rotax is responsible,------with pre-mix you are responsible :)

Tony

[CLS447]

You will just be forced to buy a 912...... or quit flying..

I think they might stop further production, but actually make us quit flying our 2 strokes !!!!!?????

Frickin Commies !!!

What next....?? Ban the parts for our 2 strokes ???

BTW .....I can't wait till I own a 912......are they getting cheaper yet ?

One more thing....I premixed for my 447 for over 20 yrs.....never had a problem, never took her apart for decarboning. I hope I get that kind of service out of my 503....just turned 50 hrs.

[Doug Riley]

I teach sailing at a commercial sailing school. The school owner, being - er - thrifty, keeps cannibalizing her collection of old 2-stroke engines to keep the whole smoky fleet running. These old kickers are pretty obnoxious for those of us who have to use them day in and day out.

The new 4-stroke outboards are just a whole lot nicer. I hope that outboard, snowmobile and jet-boat 4-strokes will provide the jumping-off point for light, cheap aircraft conversions.

Purpose-built aircraft engines like the Rotax 900's are great engines, but they are not affordable for many casual flyers. More important, it's impossible to build a Part 103 ultralight with a Rotax 912/14. If we can get a small 4-stroke from these other recreational craft to work and comply with 103, I'd be willing to put the 2-strokes out to pasture.

Maybe (cough) even my sailing boss will (cough) do the same, one of these days.

[scottessex]

The new DI 2 strokes are very clean running, and still lighter than a 4 stroke.

[phantom]

I have seen many rotax engines fail due to oil injection failure and I will not fly with it or run a snomobile, hovercraft, airboat or fixed wing, with pre mix I always get at least 1000 hours between rebuilds and some oil pumps fail at less than 50 hours

Norm

[Redbaron]

Ron nailed it! Sure you might get less carbon buildup over time but it would be better than a dead stick or worse an engine as useful as a paperweight.

Chris, you know that your not going to get rid of your oil injection, so why discuss it! Just for something to talk about?

Rotax Rick is right, oil injection is there to make it easier to use the engine..... just put gas where gas goes, add oil to the tank as needed. No need to worry about ratios or carrying extra oil on typical short cross country flights, etc...

Sure when everything works as it should, oil injection works fine. When it doesn't, your engine is fried. Simple as that.

So you have to weight the pros verses the cons.

For me, I just prefer the engine to be less complicated, less stuff to go wrong, less weight on my machine, less bulk.

[CLS447]

I guess the pump is the part that has the most failures ?

How quickly will I see the EGT/CHT start to climb, whan the oil stops squirting in ?

With all of this said, are there any others out there that are using their oil injection & are as happy as I am , so far ?

I am still riding my 05 Yamaha Zuma scooter with almost 10K miles on her. I don't even think about that failing because it is on the ground, I guess.

She takes alot of knocks & bumps & full throttle.........why would this be more reliable than the Rotax ?

[Hardy]

Chris
I've got 400 hrs. on my 503 with oil injection with no problems.

[Vance]

I guess the pump is the part that has the most failures ?

How quickly will I see the EGT/CHT start to climb, whan the oil stops squirting in ?

With all of this said, are there any others out there that are using their oil injection & are as happy as I am , so far ?

I am still riding my 05 Yamaha Zuma scooter with almost 10K miles on her. I don't even think about that failing because it is on the ground, I guess.

She takes alot of knocks & bumps & full throttle.........why would this be more reliable than the Rotax ?

Hello Chris,

I suspect the oil pump is not the part with the most failures.

In my opinion your CHT and exhaust temperature will generally not warn you of an impending lubrication failure.

I feel your scooter doesn’t need to make very much horsepower for very long.

In my opinion it probably takes less than 15 horsepower to push it down the road at 65 miles per hour.

Ten thousand miles at 65 miles per hour would be 154 hours.

Any full throttle is relatively short lived.

It appears to me that not all Rotax engines have oil pump failures.

It is my observation that people often feel they know more than the factory that manufactures 1,000 of engines after they have worked on a few 100. Every once in a long while they do find a solution to a particular problem.

Based on my involvement in warrantee cost documentation it is my opinion that most original equipment manufacturers want all the reliability they can get and work diligently to achieve it.

Most original equipment manufacturers have several people on staff that ask the question; why do we sell so many of that particular part.

There is a lot of money tied up in a reputation for reliability.

Rotax seems to dominate the two stroke aircraft market and that would suggest to me that they do a good job and probably know more about two strokes and marketing than I ever will.

Thank you, Vance

[CLS447]

Dave, thank you ! That's what I am talking about ! It will take me years to get to 400.

Thanks

Vance, Do you think the Oil Injection is good then ?

That is my 50cc scooter.......it might do 65 down a steep hill, but I figure average speed to be about 30mph & the throttle is full open more than you might think !

Thanks for the thoughts......

[Vance]

Hello Chris,

I don’t have an opinion because I have not had enough Rotax parts in my hand.

I am suggesting those that are certain that Rotax doesn’t know what they are doing may be confused.

If I had a two stroke Rotax engine I would probably follow the manufactures recommendation.

I have seen more than one two stroke engine fail because the pre-mix didn’t stay mixed.

I would try to find out what is failing and why.

With all the experience Rick has had it seems odd to me that he just now decided that he will never again use oil injection.

My experience with oil injection on two stroke engines has been positive.

My experience with two stroke engines causes me to be drawn to four stroke engines.

I feel like you are trying to get people to validate a decision you have already made.

Thank you, Vance

[GyroRon]

The last line was priceless Vance.

[Stan V]

Vance is just a priceless kind-a guy!

[CLS447]

I am trying to find out what is failing & why.

I am using my oil injection, but trying to get some real answers on how & why it is going to fail.

It would be easy for me to change my mind, & switch over to premix......very easy to do.

I am just looking for something more than some are saying.....just the facts, please.

BTW.... I am now certain that Ron says a little prayer every night before going to bed asking for my oil injection to fail, so that he can say.....I TOLD YOU SO !!

That would be easier than finding out the truth. What's up with you , dude ? Are you going to tell Dave that he is an idiot for running his 503 for 400hrs on oil injection....or what ?

Maybe we could just say some get lucky & some don't.....anything mechanical can fail even a rotorhead bearing.

[Penguin]

One of the weak points in the oil injection, IMO, is the hoses from the pump to the intake. Art - Midget on the forum - replaced his when he found them to be brittle and I'm preparing to do the same thing on mine. I haven't seen any mention of this on the various forum threads.

[GyroRon]

Chris, I don't care if you have injection or not, and I know there are people out there will far more than 400 hours on engines with injection.

What you don't see is the bigger picture.

There isn't one particular thing that causes oil injection to fail. Like Larry mentioned, the hoses can become brittle and crack. Other problems can be the filter from the tank to the pump can clog and block oil flow. Or you could have used the wrong filter that doesn't filter well enough and dirt or debris gets into the pump damaging the pump. There are plastic gears that could fail. The mechanism inside the pump itself has a small but possible chance of failure. The cable that works the pump could fail. The hose from the oil tank to the pump could harden and crack or simply slip off the tank or pump. The tank itself could break loose from its mount and fall off the machine ( this happened to a guy at my airport, and he toasted his 582 when the tank fell off in flight and he didn't know it )

All of these are not very likely to happen. But all it takes is for it to happen once and you will destroy your engine by the time you figure out what happened.

So you have to ask yourself, what benefit am I getting by using oil injection verses just pre mixing? Your saving yourself the hassle of having to pour oil into a ratio rite or measuring cup and dumping that into your gas jug and shaking, before pouring that gas into your gas tank. Thats the only real true no arguement advantage you have with oil injection. This is the same reason your scooter has injection as well, so the user of the scooter can just fill her up with gas as needed and top off the oil tank as needed. To make it easier to use the scooter.

Look at it a different way Chris... If you could identify all possible ways your 503 could fail and come up with a number, it could be say 100 ways.... example.... 1 run out of gas, 2 fan belt breaks and engine overheats, 3 carb falls out of socket, 4 ignition kill switch leads rub on airframe and short out killing ignition, 5 oil injection hose drys and becomes brittle and cracks and starves engine of oil, ETC...... In other words, you could come up with a lengthy list of things that COULD go wrong, and the oil injection system could account for 5 or 6 or items on that list. All these items could be eliminated if you just Pre Mixed!

Now if you installed everything perfectly, and kept it in perfect condition, the chances of a oil injection failure is very VERY low. No arguement there!

I just feel it is easier to just eliminate the injection and pre mix the oil and gas and that way there is ZERO chance of failure.

I don't care if you run it or not Chris. I just don't understand why you ask questions about it when you have already made up your mind?

[phantom]

the most failures that I have seen are caused by the pump drive shaft and some are due to the spring in the pump braking, these pumps are piston type and a cam pushes the piston one way and a spring returns it for the next stroke,if the spring brakes the piston will not follow the cam, the lever has a second cam that contorols how far the spring can return the piston for the next stroke, the newer type pumps have the idle stop removed and will go to max oil if the cable breaks.

Norm

[Penguin]

An alternative view of the 'more pieces, more to break' argument.

I remember my first Toyota that didn't have points in the distributor. WTF? I know how to clean and adjust points and did so with every plug replacement - all part of a tune-up. And there was all this other 'E-lec-tronic' stuff I didn't know. Over time, I learned that I got a better spark, plugs lasted longer, better efficiency. Huh. Who'd a thunk.

Then my next car - coincidentally also a Toyota - didn't have a carburetor! My father told me this was clearly a sign of the end times. I couldn't adjust the 'fool injection', even more nasty electrical stuff, and clearly I'd be at the dealer every weekend. Well, I put more than 150,000 miles on that car, had a couple of problems, but none involved the FI system. And the car started easier, used less fuel, had higher HP. Tune-ups now consisted of changing the air and fuel filters. Huh.

Sometimes - not always, but sometimes - the manufacturer really DOES know what they are talking about. Not just selling us more stuff and more service. But building a better product.

When my dirt bikes had oil injection, some owners were really leary of them. So they ran a little pre-mix, too. Thereby combining the worst attributes of each system. Yamaha was putting oil injection on their 2-strokes at least 40 years ago that I can remember. I wonder if the current crop of dirt bikers remove their oil injection, run some pre-mix, too, or simply accept the technology.

[scottessex]

I know that some people here believe that Oil is Oil and it does not matter,
use whatever is on sale etc..... but if you plan to run oil injection, make sure that you run INJECTION oil!! don't just go to wal Mart and buy whatever 2 stroke oil is on sale and dump it in the oil tank...injection oil is much thinner viscosity than premix oil..
The main killer of an oil injection system motor is lack of maintenance on the oil flow cable. And using too thick of oil for the pump gears to deal with. just my $.02

[GyroRon]

Larry, most dirtbikes these days are four stroke. The 2 strokes still made over the last 10 years or so all require pre mix.

My first dirtbike, I was 8 yrs old back when I got it, was a yamaha with oil injection. I toasted the piston in it due to a problem with the oil injection.

[Penguin]

I holed a piston in my DT3 when a reed valve gave up.

[GraemeClarke]

When we first started running oil injected outboards we had a lot of failures. The problem turned out to be that we were useing thick premix oil rather than thinner injection oil. The premix was the outboard brand, and they never told us we had to use a different oil.
Graeme

[Penguin]

Larry, most dirtbikes these days are four stroke.

Ron - do you know that those 4-cycle mocycle injuns have valves, valve springs, keepers, camshafts and --- you better sit down for this --- OIL PUMPS?
OMG, the inhumanity!
Death traps is what they are.

OK, I've had my fun.
I can't wait until I have a modern 4-stroke with DI hanging on my gyro.
Until then, I'm following the manufacturer's recommendations on my 2-stroke.

[GyroRon]

Larry, I know! Thats why the bikes in my garage are both 2011 KTM's, a 200xcw and a 250sx.... both 2 stroke!

We have had 3 different 582 powered airplanes toast their engines with oil related issues at my airport in the last few years. All had oil injection.

[Redbaron]

Larry, I know! Thats why the bikes in my garage are both 2011 KTM's, a 200xcw and a 250sx.... both 2 stroke!
.

Ktm came to my mind too. Ktm needs to get their jetting right cause the last time I rode behind one all I saw was exhaust smoke. Maybe that is normal tho :-)

[CLS447]

One of the weak points in the oil injection, IMO, is the hoses from the pump to the intake. Art - Midget on the forum - replaced his when he found them to be brittle and I'm preparing to do the same thing on mine. I haven't seen any mention of this on the various forum threads.

Excellent point & one that I have been waiting for ! Are you going to order new clamps for both ends of the hoses ? Where are you getting that stuff from ?

If you pay no attention to those hoses you could get in trouble ! They are main arteries to the heart !

I would also like to safety tie the hose clamps to the intake nipples somehow.

Obviously you guys are enjoying the convenience of oil injection also .

[CLS447]

Larry, I know! Thats why the bikes in my garage are both 2011 KTM's, a 200xcw and a 250sx.... both 2 stroke!

We have had 3 different 582 powered airplanes toast their engines with oil related issues at my airport in the last few years. All had oil injection.

That sucks ! What part failed ? Help me out here !

[CLS447]

I started a list of the benefits of oil injection but the post got lost....

Let's start another......

1. Never have to premix.
2. Keeps fuel fresh longer ?
3. Keeps oil from breaking down ?
4. Never run premix though the carbs.
5.At low RPMs you don't need 50:1 ratio (less carbon )
6. ?

I know there are more....

[Penguin]

Excellent point & one that I have been waiting for ! Are you going to order new clamps for both ends of the hoses ? Where are you getting that stuff from ?

If you pay no attention to those hoses you could get in trouble ! They are main arteries to the heart !

I would also like to safety tie the hose clamps to the intake nipples somehow.

Obviously you guys are enjoying the convenience of oil injection also .

My brother is placing an Aircraft Spruce order and I asked for the smallest double-ear clamps. Unfortunately, those are listed as 1/4". I believe the hose is actually 1/8" plus whatever it swells to on the manifold nipple. So I'm not sure they will work on the oil injector lines. I'm also unclear on how to bleed them so they don't start dry.

Speaking for myself, I don't use the oil injection because of convenience. I use it because I feel it is better. My brother, OTOH, uses pre-mix because he feels it is better. It's like arguing religion - there is no end to it.

[scottessex]

You probably should check with lockwood to see if they have what you need.

[Penguin]

Good suggestion, Scott.
I'll give them a shout today.

P.S.
Yes, they had them.
I ordered some hose and clamps.
Thanks again for the suggestion, Scott.

[Joe Pires]

Never saw an engine with pre-mix get starved of oil, only injection... just sayin.

Never saw an injected engine forget to add oil, because it got distracted on pre-flight only pre-mix...just sayin.

[Joe Pires]

I'm also unclear on how to bleed them so they don't start dry.

I sure could be wrong, but what I understand is you premix the first tank then when your done look at the tube to make sure the oil worked its way through the tube.

[scottessex]

There should be a bleeder screw on the pump also, but yes Joe, run engine on pre mix until the air is gone..

[Penguin]

I sure could be wrong, but what I understand is you premix the first tank then when your done look at the tube to make sure the oil worked its way through the tube.

Ah, Gees, Joe.
Now you just gave Ronnie fuel for another diatribe!

[Ronnie328]

I started a list of the benefits of oil injection but the post got lost....

Let's start another......

1. Never have to premix.
2. Keeps fuel fresh longer ?
3. Keeps oil from breaking down ?
4. Never run premix though the carbs.
5.At low RPMs you don't need 50:1 ratio (less carbon )
6. ?

I know there are more....6. Injection keeps you under warranty.

[DennisFetters]

I sure could be wrong, but what I understand is you premix the first tank then when your done look at the tube to make sure the oil worked its way through the tube.

You are correct, in fact. This will also help for your engine break-in.

Always use the oil injector on your Rotax. Don't let people talk you out of it, it's not their engine after all.

Like;

Always your your helmet when riding your motorcycle. Don't let people talk you out of it, it's not their head after all.

Read my reasons in the first of the thread as to why you should always use oil injection, it makes perfect since.

[CLS447]

What chuck said about a helicopter is true, but about being no advantage in a fixed pitch application is just absolutely wrong. I suggest that if you are going to listed to advice, at least make sure the person has gone to the authorized Rotax overhaul and maintenance school.

Here is just some common since information I posted here some time ago;

"""Always use the oil injector. Never allow yourself to be talked into taking it off, because "it's just something else that can fail" reason. Oil viscosity is what protects your engine. Mixing with gas will lower the viscosity and give much less protection and reduced engine life. Oil injected into the ports brakes up into micro-beads of oil, but each still have their high viscosity for protection.

The only two things that wear out the Rotax engine that has been properly installed and cooled, is poor lubrication and carbon buildup.

When Rotax first offered oil injection, there were a few problems. It was not the oil injector failing, but contamination that was somehow getting in the oil that was causing the failure. Rotax made it mandatory to use a special filter between the tank and injector, and all the problems went away, and that was years ago.

There is no good reason not to use the oil injector, and there are many good reasons to use an oil injector.

1. Better lubrication from higher viscosity oil droplets.

2. Uses much less oil then mixing, reducing pollution, carbon buildup and smoke.

3. Oil injected droplets tend not to burn as much, or in the bad way that mixed oil does. Mixed oil burns dry and causes buildup, while injected droplets tend to stay wet and burn in the exhaust system, clogging rings to a much lesser degree.

4. You can take much longer trips using oil injection, because you don't need to add oil for up to 10 fill-ups, while you need to mix every time you fill-up.

5. You don't need to carry oil with you on cross country flights when you fill-up at other locations, mixing oil you do.

6. You can go up to 10 fill-ups before having to remember to add oil when you have an oil injector. You have to remember every time when mixing.

7. I have had only 2 Rotax engine failures out of the thousands of hours I have flown gyros. Both were due to not mixing the oil with the fuel. I have never had a single engine failure since I started using oil injection.

Why would anyone not use oil injection?""

There it is ! Thanks Dennis !

[GyroRon]

I still believe the oil injection is there mainly to make it easier to use the engine, not for anything else.

Look at the 503's oil injection and tell me this wasn't engineered as a afterthought.

Why didn't the 447 ever come with injection?

And the 582 and 618, being sled based engines, did come with injection... why not though since the sleds had it. Why did the sleds have it... to make it easier to use the sleds, oil in one tank, gas in the other.

Jet skis for example... Most are now four stroke powered, but before switching to 4stk power, they were 2 stroke. All the big 3 seater skis offered oil injection, even some of the 2 seaters. But not every model had it. My jet ski, a Kawasaki SXR800 doesn't have it, and they made this model up till last year, never had oil injection. Same thing with the yamaha super jet which is still in production, no oil injection. Why? Because the people who ride superjets and SXR's are not the same kind of people who ride big 3 seat cruisers, we don't mind pre mixing our gas. We also only have 5 gallon fuel tanks and therefore limited range, so having oil injection where we could fill the oil tank and burn through 3 or 4 tanks of gas is impractical.

If oil injection was so much better for your engine, why would Yamaha and Kawasaki offer jet skis, with warrantys, to the general public, without oil injection?

In nearly every case, if you stop to really think about why any recreational two stroke engine has oil injection, it is clearly there to make the engine easier to use.

Are there benefits from using oil injection, besides making it easier to fuel up the gas tank? Sure. But there is also drawbacks as well.

I don't have a problem pre mixing my fuel. I do 10-15 gallons a week as it is for work and play and have done so for years. It isn't hard.

Talk about it, debate it all you want, but the bottom line truth of the matter is..... As long as you pre mixed your fuel, the engine will not have oil related issues! There is nothing to fail. With the injection, there are many points of failure. This can't be argued.

[DennisFetters]

I still believe the oil injection is there mainly to make it easier to use the engine, not for anything else.

Look at the 503's oil injection and tell me this wasn't engineered as a afterthought.
Why didn't the 447 ever come with injection?
[/U][/B]

Well, I don't know about the other brands or applications you mentioned, I only went to the Rotax Aircraft engine overhaul and maintenance schools in Canada, so I will only give advice on what I know for sure.

Yes, oil injection came out later on the 503's and it was an afterthought, so they had a reason. The 447 was discontinued so there was no need to make the upgrade.

But, you are right; people are going to do what they want no matter the logic presented.

[Not Yet]

The new SDI & DI Rotax sled engines must be oil injected because no gasoline is ever in the crankcase.
The 2009 Ski-Doo 600 E-TEC is one such engine.

[DennisFetters]

I found this published by Published by Aero Population Technologies and thought it was a good addition to this thread;

Why Choose Oil Injection on Rotax Aircraft Engines?

All Rotax 2-stroke Aircraft Engines (except the 447 UL) are now provided with an oil injection pump. But because of a lack of an adapted mounting system (as is the case for the Quad City Challenger / Challenger II Ultralight), or because of dubious superstitions, some planes are still not equipped with oil injection.

The principle of oil injection rests in the separate intake of oil and fuel/air mix rather than the premixing of both. An engine driven pump regulates the flow of oil and injects it into the engine via the intake manifolds. Such systems have been used on 2-stroke engines since the early 60s, but it is only since 1989 that Rotax has been using them on their aircraft engines, starting with the first 582 UL. Faithful to their tradition of reliability, Rotax waited for the system to be thoroughly proven before using it on their 2-stroke aircraft engine range.

Advantages:
•More convenient
No need to premix your fuel. Simply fill up with pure fuel and ensure that your oil tank is always topped up.

•Less carbon accumulation
The major part of carbon accumulation in 2-stroke Aircraft Engines takes place at idle, a speed at which they do not actually require as much as a 50:1 ratio of oil. The oil injection pump regulates only 70:1 at idle, therefore limiting carbon accumulation. At higher RPMs, the ratio is brought back up to 50:1.

•Less engine wear
The lower amount of oil at idle also helps prevent the wear caused by excess carbon deposits.
With oil injection, the oil circulates through the engine better and ensures better lubrication. Furthermore, the alcohol contained in the majority of fuels reduces the oil's lubricating efficiency when pre-mixed. Oil injection prevents this reaction from happening and ensures that the oil maintains its peak efficiency.

•Cleaner inside
When oil injection is used, only pure fuel flows through the fuel system and carburetors, keeping everything clean. Otherwise, when premixed fuel evaporates, it leaves the oil's varnish deposits behind, quickly contaminating the fuel system and carburetors.

•Cleaner outside
An oil injected engine's emissions are reduced thanks to the lower oil ratio at idle. In addition to the environmental advantages, the difference becomes quickly obvious in terms of exhaust deposits on your aircraft and propeller.

•Eliminates the risk of pre-mixing mistakes
How many times did you ask yourself if you did put the right amount of oil in your fuel? Or if you even forgot to add it? Those risks are completely eliminated. Simply keep the 2 liter (about 5 hour's flying capacity) tank topped up. A level sender can even trigger a warning light on your instrument panel to indicate low oil.

•Preserves octane rating
Most 2-stroke engine oils cause the fuel to lose up to two octane points when pre-mixed.

Installation criteria
•The tank should be placed so that its outlet is always higher than the pump under any flying attitude, so that the pump is always gravity-fed.

•The oil line and oil filter have to match Rotax standards.

•A few precautions have to be taken during the first run: It is important to bleed the system to free any air bubbles; the oil injection lever cable has to be adjusted so that the marks on the lever and pump align at idle; the first tank should contain 100:1 premix to ensure that the engine will receive adequate lubrication while any last air bubbles go through.

Don't wait!

•On a new engine:
Your new engine will be provided with an oil injection pump. You will just have to add an oil injection tank and a 3-way throttle control cable to actuate the pump lever in addition to the two carburetors.
Note: Certain manufacturers (notably Quad City, manufacturer of the Challenger) provide an engine without oil injection with their kit. It is more advantageous for you to buy your engine through us since for the same price you will have oil injection included.

•On an existing engine:
Most existing engines of types 503 UL, 582 UL and 618 UL can have oil injection retrofitted. You need to add an oil injection pump and change the intake manifolds. You will also need the oil injection tank and a 3-way throttle control cable to actuate the pump lever in addition to the two carburetors.

[Penguin]

I'm experimenting with pre-mix while making a cake. Following the argument that if I pre-mix, every bite would always have frosting, I pre-mixed the frosting with the cake mix, guaranteeing that every bite always had frosting.
The result was neither a good cake nor a good frosting.
:puke:

As Dennis' article indicates, adding oil to the gas lowers the octane of the gas. And adding gas to the oil reduces the efficacy of the oil.

[Earthboundmisft]

Interesting...
Every carbureted 2 stroke Mercury outboard uses the Mikuni oil injection pump.
The oil exits the pump, and is entered into the FUEL LINE,
then goes to the CARBS.:censored:

[Penguin]

Interesting...
Every carbureted 2 stroke Mercury outboard uses the Mikuni oil injection pump.
The oil exits the pump, and is entered into the FUEL LINE,
then goes to the CARBS.:censored:

Actually, the oil injection pump feeds the fuel line before the fuel pump which then feeds the carbs. Merc may be using the fuel/oil mix to lube the fuel pump as well.
There is a big difference between oil in a fuel solution for weeks/days/hours as opposed to injecting it at the last practical point before introducing it to the crankcase.

[opsled]

Actually, the oil injection pump feeds the fuel line before the fuel pump which then feeds the carbs. Merc may be using the fuel/oil mix to lube the fuel pump as well.
There is a big difference between oil in a fuel solution for weeks/days/hours as opposed to injecting it at the last practical point before introducing it to the crankcase.

Yamaha started injecting into the fuel lines prior to pump in 1983 on sled engines. Later setups had ports right on the pumps for injection lines. It's a great setup. As far as I know they were the first to come up with an injection system for oil on a two stroke. That happened back in the 60's on street bikes. As others said it was mostly a convenience issue to make a production machine more user friendly. It would also help eliminate user error in premixing that could damage an engine.

Old fuel is junk premixed or not. In my opinion premix is just as good as oil injection if done properly. Oil injection is easier to deal with. Personally I like oil in my carbs for many reasons but I don't like to premix so I like the injection into line/pump system.

If a person knows what they are doing there is nothing wrong with premix.

opsled

[themonarch]

Back in the 80's I was into having my sno-mo engines modded. I wanted something faster than stock, no matter what stock. At that time Yamaha was injecting the oil into the fuel lines, upstream the carbs. Performance shops such as PSI Peformance, Wild Rose Wisc., were concerned that this method lacked proper timing when considering rapidly changing engine rpm's. Subsequently PSI encouraged oil injection into the intake manifolds to better "time" the best ratio of oil to gas to the particular engine rpm. I made these changes to my systems because it made sense to me. If there was a burndown it was not due to lack of oil, but lapse of proper timing of overall fuel delivery. Eventually I eliminated this variable by reverting back to pre-mix. Proper carbureator calibration is everything folks, remember, for this is key. Especially with 2 strokes. MJD.

[bryancobb]

JUST THE FACTS SIR!

* No debate about injection being convenient
* No debate about less ring-groove clogging and plug-fouling
* All other aspects can be argued and debated.

My friend just this past week sent his grayhead Rotax 582 to a highly respected and well known rebuilder for a complete 300hr rebuild. The rebuilder, has been an A&P/I.A. for deacdes, and has worked on hundreds of general aviation engines. For the last ten years, he has almost exclusively worked on Rotaxes.

My friend's engine was rebuilt at 300 hours TTE, before he bought the Kitfox III it has always been in. Now it has just over 600. I can't remember if it got a new crank at 300 or not. It does have very complete logs, so he knows every part ever replaced and how it has been operated.

After disassembly, the guy calls my friend to report what's needed. He reports "Everything looks great. However you have been operating it has served you well. The ring grooves are very clean and the rings were free. The crank looks great and doesn't need replaced. It's perfect. All you need is pistons and rings and the cylinders need to be put back to non-worn geometry. (In 600 hrs you would EXPECT some wear)" He also said "There was some carbon buildup on the crown of the pistons."

Then he tells him all the changes he suggests like REMOVING THE OIL PUMP, CHANGING THE JETTING, AND CHANGING OIL TYPE AND MOVING THE JET-NEEDLE CLIP POSITION, AND CHANGING THE IDLE JETS, ETC ETC!!!!"

I don't get it! If the crank is perfect and the rings free, And my friend has flown 300 hours with ZERO issues and no engine failures, I don't understand why this EXPERT wants him to make ANY changes! If it ain't broke, don't fix it.

Now I understand that a fresh engine MAY require jet changes because, in theory, it will be a tighter, more efficient air pump now, but if I was the expert, I'd say..."DO NOT CHANGE A THING! JUST GET THE NEXT 1 OR 2 LEANER MAIN JETS AND NEEDLE JETS JUST IN CASE IT'S TOO RICH ON THE ONES YOU HAVE BEEN USING.

[Penguin]

@bryancobb - But you are overlooking the tremendous horsepower increase from removing the oil pump. Not to mention the weight reduction.
Vroom vroom!

[bryancobb]

@bryancobb - But you are overlooking the tremendous horsepower increase from removing the oil pump. Not to mention the weight reduction.
Vroom vroom!

Horsepower is in the form of "pent-up" energy in the gasoline. I can't get my mind wrapped around how having MORE oil in the gas, and the tiny energy loss in spinning an oil pump shaft robs a TREMENDOUS" amount of horsepower. You have GOT to

When oil-pump removal/pre-mix advocates show me certified dyno-plots and I'll remove every oil pump myself! :)

[Penguin]

Parasitic drag - probably good for 15 or 20 hp, right?
Nahh. I'm messing with ya.

[bryancobb]

Parasitic drag - probably good for 15 or 20 hp, right?
Nahh. I'm messing with ya.

LOL! I posted it without finishing my last sentence that said "You have got to BE joking."

[themonarch]

No matter what, diesel, (especially diesel), 4 stroke gas or 2 stroke gas, being oil injected or not, they All run rich cold. We expect that. You see a lot of extra smoke from a cold diesel then less from a two stroke premix. Even less from a two stroke oil injection and finally least of all, less smoke from a cold 4 stroke. I don't know about kerosene turbines maybe someone can chime in here about that.

Because on cold start my pre mix 582 shakes too much and spews a lot of smoke (not that smoke is so important as long as nothing is on fire! ). I asked the tech's at L.E.A.F. "how long do I have to wait before I can raise rpms to 2600 to get away from these disturbing annoyances?". The response was "go direct to 2600, this will not hurt the engine". By the way, as I am told, at 2600 you go past the sprag clutch if you have one, so what good the sprag clutch in this cold engine situation? Probably a clutch has benefit in other situations. I am not taking issue here, only musing.

I am not sure that going quick to higher rpm's at cold start really is okay. I think that it depends on how cold is it at the time, so you have to know your feel for things.

My experience is that pre-mix is not really loading up your engine as compared to oil injection. It's just a cold two stroke, that's all. The engine is cold for only few minutes, then it's all whisked away by more gas, higher engine temps and rpm's so no matter. I feel that it's more important the choice of oil. By my experience I prefer synthetics. Pre mix or Autolube? To each their own. MJD.

[opsled]

Back in the 80's I was into having my sno-mo engines modded. I wanted something faster than stock, no matter what stock. At that time Yamaha was injecting the oil into the fuel lines, upstream the carbs. Performance shops such as PSI Peformance, Wild Rose Wisc., were concerned that this method lacked proper timing when considering rapidly changing engine rpm's. Subsequently PSI encouraged oil injection into the intake manifolds to better "time" the best ratio of oil to gas to the particular engine rpm. I made these changes to my systems because it made sense to me. If there was a burndown it was not due to lack of oil, but lapse of proper timing of overall fuel delivery. Eventually I eliminated this variable by reverting back to pre-mix. Proper carbureator calibration is everything folks, remember, for this is key. Especially with 2 strokes. MJD.

I like my oil injection but have no issues with premix and use it too depending on what the engine is being used for.

Dynotech, PSI, Bender and others all scoffed the Yamaha system of injecting into the fuel stating the reasons you describe.

Problem is they were/are wrong. There argument is based on the belief that oil injection varies the ratio of oil/fuel mixture for various rpms/loads. If that were true they would be correct.

Fact is that oil injection is designed to keep the oil/fuel ratio constant and consistant with the fuel use rate. The oil/fuel ratio in the carb bowls on the Yamaha system is always the same. The aftermarket direct injection systems sold by these companies didn't hurt anything but they were sold under a false premis and were not needed. A lot of wasted money by consumers.

Personally I havn't seen a bad injection system yet. Some use better quality components than others. Some are more prone to failure but I havn't seen anything that would cause me to call them all junk. I also don't think there is any real world proof that premix is bad or not as good as injection.

Test results are often scued to reflect the objective of the test.

opsled

[Penguin]

Fact is that oil injection is designed to keep the oil/fuel ratio constant and consistant with the fuel use rate.
opsled

I'm pretty sure that is incorrect.
All modern systems vary the oil injection with throttle position. The Rotax range is 100:1 at idle and 50:1 at full throttle.

[opsled]

I'm pretty sure that is incorrect.
All modern systems vary the oil injection with throttle position. The Rotax range is 100:1 at idle and 50:1 at full throttle.

You are correct in that all two stroke oil injection systems vary their rate "ratio" with throttle position and that they are variable rate "ratio" pumps. They have to be in order to keep a consistant oil/fuel ratio under all rpm/load conditions.

The oil pump has two methods of increasing the amount of oil it pumps. One is with rpm from it's drive. Increase rpm and oil flow increases. The other is by increasing the stroke on the pump which is done by moving the arm on the pump. This is seperate from the drive and tied to throttle to compensate for increase fuel use rate because of load.

An engine under no load can achieve 6000 rpm with very little throttle and very little fuel consumption. An engine under full load will need much more throttle to achieve 6000 rpm and with the increase in throttle it will use more fuel. The variation of oil flow because of rpm is not enough to be consistant with these two senarios. In order to keep a consistant ratio at all rpm and loads the pump must have the ability to increase oil flow rate to match fuel use rate. That's why the rate is increased with the ratio change via a connection to throttle position.

A variable rate or "ratio" pump is a MUST have in order to keep consistancy in all rpm/load conditions.

opsled

[akoschier]

I for one ruined a very expensive Hirth 3701 with Carbon Pistons due to an injection pump failure. The Carbon pistons made the failure benign - gradual power loss- but the engine stopped after a few minutes and seized. Taking the exhaust manifold, off blued needle rollers from the connecting rod bearing fell out. Sent the engine back to Hirth who initially did not want to believe the pump had failed. Have not heard from them back yet.
This was the end of me using 2 cycle power.
avk

[Stan V]

It's been said here before, friends don't let friends fly with a Hirth. I sold my BD5 last week, when they first came out, the Hirth was its bigest failure, the Turbo Honda made it a much better and safer plane. PRA 41973

[Redbaron]

It's been said here before, friends don't let friends fly with a Hirth. I sold my BD5 last week, when they first came out, the Hirth was its bigest failure, the Turbo Honda made it a much better and safer plane. PRA 41973
They only hirth one time. :-)

[opsled]

The snowmobile industry quit using Hirth in and around the mid 70's.

They only had to walk home when one went down..

So,,,,

opsled

[themonarch]

Opsled, say no.. You can't mean the 650 Hirth Red Baron? Tug tug tug on a humgous two cyl. two stroke. (It won a few in it's day). Opsled, you are approaching being sacraligius, mind you sir! Best be carefull if the ole time sledders find out what you say.. I'll stay mum. MJD.

[opsled]

Opsled, say no.. You can't mean the 650 Hirth Red Baron? Tug tug tug on a humgous two cyl. two stroke. (It won a few in it's day). Opsled, you are approaching being sacraligius, mind you sir! Best be carefull if the ole time sledders find out what you say.. I'll stay mum. MJD.

LOL, The Hirth engines are still alive and runnin in the vintage world. They were used in many machines back in the day and there is no shortage of love for them. I've owned two in my life and wish I still had them. One was an 800 free air tripple in a Rupp Magnum and the other was the famous 650 Red Barron in a early 70's Air Cycle hovercraft. (google it, they were cool).

No oil injection though, a bit early for that. There were many such engines back then from many other manufacturers. Most are gone now.

Cool stuff though,

opsled

[CLS447]

OK.....what's up with this ? I got 2 stroke oil dripping out the bottom of my dual air filter. (503DCDCDI)

It would seem that oil is draining out of my tank, through the pump,through those small hoses, into the intake , through the carb throat , & out the air filter,& onto the floor !

My oil tank is mounted up the mast, about a foot higher than the pump. I refuse to install a shutoff valve on the tank for obvious reasons.

Is this typical or are my check valves not working ?

This is a great reason for my intakes & carbs to tilt away from the engine.

What do ya think ??

[Penguin]

Chris - I don't think it is happening as you describe.

Try this for verification - pull the tops on your Bings and lift the slides out. I suspect that you'll find them well coated in 2-stroke oil. That's what I observe on my 582. IMO, no amount of leakage could result in oil backing up onto the slides. It would simply run out the carb and onto the air filters.

I believe that a mix of gas and oil is being blown back from the intake as a result of reversion. This is equally true with oil injection or premix. You may also observe a puddle of 2-stroke oil under the air filters has formed over night. Again, not leakage, but the result of the air filters getting 'wet' from the fuel/oil mixture, the excess dripping out, and the fuel evaporating.

You are right - don't put a shutoff on your oil supply in any case. But you might try marking the oil reservoir with a bit of tape and pencil just to reassure yourself that oil is leaking by the oil injector overnight.

I hope this makes you feel better that everything is up to snuff.

[DennisFetters]

OK.....what's up with this ? I got 2 stroke oil dripping out the bottom of my dual air filter. (503DCDCDI)

It would seem that oil is draining out of my tank, through the pump,through those small hoses, into the intake , through the carb throat , & out the air filter,& onto the floor !

My oil tank is mounted up the mast, about a foot higher than the pump. I refuse to install a shutoff valve on the tank for obvious reasons.

Is this typical or are my check valves not working ?

This is a great reason for my intakes & carbs to tilt away from the engine.

What do ya think ??

I think ya got a banjo valve leaking.

[GyroRon]

Chris - I don't think it is happening as you describe.

Try this for verification - pull the tops on your Bings and lift the slides out. I suspect that you'll find them well coated in 2-stroke oil. That's what I observe on my 582. IMO, no amount of leakage could result in oil backing up onto the slides. It would simply run out the carb and onto the air filters.

I believe that a mix of gas and oil is being blown back from the intake as a result of reversion. This is equally true with oil injection or premix. You may also observe a puddle of 2-stroke oil under the air filters has formed over night. Again, not leakage, but the result of the air filters getting 'wet' from the fuel/oil mixture, the excess dripping out, and the fuel evaporating.

You are right - don't put a shutoff on your oil supply in any case. But you might try marking the oil reservoir with a bit of tape and pencil just to reassure yourself that oil is leaking by the oil injector overnight.

I hope this makes you feel better that everything is up to snuff.

I agree with what larold just said above

[CLS447]

Great ! That'll keep that K&N well oiled !

[Penguin]

Great ! That'll keep that K&N well oiled !

Not really, but I think you know that.
The oil just drools out the bottom of the filter.
Assuming you have a K&N, it needs to be pulled, cleaned and oiled regularly.

[cburg]

E-mail sent and received today about a trike friend's 582:

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Did she seize up? Do you have an oil injector? RotaxRick is strongly against injectors and advocates 40:1. I'll paste some info below:

I never have used an injector, but some people love them.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Yes I have the oil injector and yes it did momentarily seize/quit. And of course it restarted after landing back on the runway. An inspection of the pistons/cylinders through the exhaust port did not find anything abnormal ...

Charles J. Glynn, Ed.D., P.E., CSP