Webber 750 engine

Hi Mark

I used the original snowmobile fuse block (redesigned) between the ECU and the engine and yes I shielded ALL of the trigger inputs (quite some work but thought it desireable since DIY made a point to mention it). Bought shielding from Wicks I think, the wiring looms are STUFFED FULL . I think some of the pictures may show the shielding going to a common ground on the firewall. If you want to get one of the fuse blocks like the snowmobile used, I found the source for the parts (brand new) at Mouser electronics, have the part numbers somewhere. You will have to put in the pins and program it like you want it ( a lot easier when it's new). The fuse block has 4 relays and 4 fuses and 2 spare fuses.

On the Microsquirt, the FP turns on for 2 seconds, primes the system then shuts off until the engine starts cranking and runs.

Tony

PS I used both sides of the Bosch MAP/AIR TEMP sensor and no I dont have a knock sensor.
 
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Mark

why use a fiddle valve or a stepper motor, just prime it and the ECU takes care of the need for enriched fuel when cold, via the coolant temp sensor, use a little extra throttle while cold like you would on any aircraft engine. It will be warm before you take off.

Tony
 
Mark, I even shielded the wiring to the injectors and to the ignition coils all the way from the ECU, thru the firewall connectors and to the coils and injectors (fun??) Was thinking about radio noise also.

Tony
 
Tony,
I don't see anything wrong with priming the engine. Thats what I do with the Rotax. It would just be nice to keep it as original as possible before I start removing anything else. One of the nicest things to me about the Yamaha was the way it started.
I will soon find out. I plan to wire it in this weekend.
On another note, I read on Compact Radials web page, their clutch driven PSUR is rated at 130 hp at a cost of about 1600.
 
Mark

I looked at that site you just mentioned and that re-drive is quite interesting and a great price too. I don't know how well it would adapt to a damper drive and a flywheel.

The clutch is ok on the two stroke since it has a lot of "mass" in the crank but I think the four stroke is going to require a flywheel to stay out of trouble with reasonance.

If it could be adapted to a damper set up I think it would be a real prospect, and a great price.

Am going to have to make my oil tank, my "expensive" idea about the lawnmower gast tank just is not going to pan out, just another minor delay :)

Tony
 
Hey Mark

Also look at the rpm max on the re-drive ??

Tony
 
Waiting on Neal, told him I was in no rush.

Tony
 
Neal's use of the Centaflex is what makes it easier to adapt a damper rather than a spline.

Tony
 
Good morning Tony, Mark, and Friends...
I've been out of touch for the last 6+ weeks.

Buddy can you give me an update as to how far along you guys are?

I'm overwhelmed with all the work that as been delayed because of family obligation and do not have time to read the thread from where I left off reading and would like to know how you are progressing.
 
John,
We are all at the age that family obligations play a big role in our responsibilities. We take care of our young and our older family. God Bless them all.

From my project,
I removed all of the Polaris ECU and most of its wiring. I have built and mounted the engine to a test stand. I have modified the original Megasquirt to the Megasquirt Extra configuration.
I have tested the Megasquirt on the Stimulator and believe it to be working properly.
I hope to wire it to the Weber this Weekend.
I need to install a radiator, oil cooler and gas tank to the test stand.
I need to order a Wide-band O2 sensor with the gage for the Weber.
On the turbo side, I have not decided on the heat exchanger for the air and I have not decided on whether to tie the driver for the waste-gate to the Megasquirt or go with an independent device. I will probably get the engine going to get some hours on it and work out the Turbo .

I also have another ECU , I will give details on a bit later, that hopefully will be a plug and play.
I purchased a laptop Yesterday to be able to tune and program the Megasquirt on the engine as required.

I have the new firmware downloaded in the ECU and the associated program for Tuner Studios on the Laptop. I do not have the upgraded program that allows the logging and some other features on the Laptop. I may have to purchase a separate license of it as well.

Got to go, lunch is over.
 
Hi John

Well here at the "turttle race track" things are just putting along. Got the Microsquirt ready to program, but that will be done by my computer whiz neighboor, who has a whole bunch of family issues over the last month so the ECU has not been programed or tried. Am working on my oil system, spent 3 to 4 hundred on designing it, got a lot of expensive fittings before I got the arrangement I wanted and then bought a $65 gas tank for my oil tank and now have decided to make my own as the other just did not meet what I wanted, waiting on Neil for the re-drive but told him I am in no hurry, so all in all am moving about an inch at a time with many yards still to go.

But all this keeps me out of the bars, off the streets and don't have any money left for the girls so not much chance of getting into trouble.

Look to see some progress over the next 2 months.

Tony
 
More information on fittings for the engine oil intake

More information on fittings for the engine oil intake

The pictures below kind of show what has been happening with the oil system I am making for the Weber. The first picture shows 3 types of fittings, on the left is a banjo fitting with 10AN male thread with a 10AN "aggressive" hose barb (more on this later) the one in the middle is the one I just got from ROTORTECH (had to order from John in Germany) and the one on the right is the biggest I could find in the States. The first 2 have a 1/2 inch dia hole, the one on the right has a 3/8 dia hole (to much restriction).

The second picture shows 2 different double banjo bolts, both came from Hydrualic Supply Company, when I ordered 6 they were out and when they shipped I got two differents styles. To me there is a very important difference here and it is the length not the holes. The one has 3 holes bored at 120 degrees, a little larger and with champfered edges (nice) the other has 4 holes (a little smaller) cross bored and sharp edges. Both have about the same "total" flow diameter so flow capacity is more or less the same. The main difference is the one with 4 holes has about 2 or 3 threads more length giving it more length from the bottom of the head to the end of the bolt. This becomes quite important when we get to the crush washer seals.

The copper washer is about .035 thick the aluminum is about .055 and the washer with the molded buna rubber seal is about .080 thick. On the shorter bolt I would only use the copper washers and then the number of threads is just barely sufficient in my opinion. The longer bolt gives me some options of mixing the washers and using 1 or 2 of the rubbers seal washers. The shorter bolt measures about 2- 1/8 and the longer measures about 2-1/4.

The banjo fittings are about .780 thick, however one banjo fitting that I ordered that had a female 3/8 pipe thread in it ( was going to put in a drain valve) measured about .880, expensive but could not use it. One final word, about the hose in the picture. When the manufacture of these "aggressive,no clamp needed" hose barbs says to heat the hose in boilng water and use some grease inside the hose -------THEY MEAN IT!!!!!

No way is that hose coming off under low pressure, if you make a mistake and get it about half way on, you are going to CUT IT OFF !! Last 2 pictures are duplicates.

Thought I had found a source for the banjo fitting in Canada at Williams Fluid Air Co. but it turns out that although they show it in the catalog they do not stock it and do not seem like they want to order it either (guess what, it comes from Europe) .

Tony
 

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Oh yes, I for got to mention the reason for the 2 banjo fittings, one will have a short smaller hose on it with a drain valve at the end which will allow me to place the drain where ever I want it and this will allow me to drain the tank without having to use a suction gun like on the snowmobile.

Tony
 
Way back on page 30, post 449, the picture shows a Weber with what looks like a pair of K&N filters. Anyone know what size these are or the part number for them or the cone version ???

Tony
 
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Hey Mark

What's happening with your Weber ? Still making lines and hoses for my oil system, and finally have designed my oil tank the way I want it, now to get it welded up. Think I found the part number for the K&N filters I want (RC-1252 ) Boy are they expensive, about $ 69 bucks plus freight, order anyway should be in Fri.

Found I needed a "beading" tool in making up my oil lines, looked up the prices !@#$%^& TO MUCH. So am now trying to make one from a old flaring tool.

Tony
 
Tony,
I started the Weber on the Megasquirt and have not touched it since. I have been making some parts on the CNC mill for some other gyro owners and helping my son get my old Bensen going so he can begin his crow hops. I have one more rotor brake and one rotorhead to get finished, then I will start on the cooling system so I can get some running hours on the Weber. I am probably going to ditch the Rotax gearbox and get the MZ gearbox with clutch. Not sure about that, I wish I had one to look over.

Have you thought about your cooling system yet? I think I will go with the alum Honda Civic radiator. It is smaller than the rabbit radiator.

My mother has been sick off and on again, so its make parts in between the time I work and take care of her.
Post some more pictures when you get a chance. They help me think! lol
 
Hi Mark

Sorry to hear about your mothers health, I know the situation. I am like you, I would sure like to see a design layout of the MZ gearbox, have never seen even a picture of one dis-assembled. Should be getting one from NZ in about "2 weeks" (or so) maybe. The main thing that has me tied to Neil"s gear box is the way he ties the spur gear to the damper, I don't like using splines in a re-drive, they are a potential source for wear.

As for the radiator, The best and cleanest set up I ever saw on a open frame pusher gyro was done by Dave Pike years ago. It was a Chevy Geo-Metro radiator (same as a Suzuki Swift). They make them in both brass and aluminum and in single row and double row cores. His was a double row, these are used on the car with airconditioning. I think the car was in the "90s model. The radiator was used on a direct drive EA-81 Subaru, never had a problem with it getting hot. The EA-81 is 1800cc so it should handle the Weber fine at 750cc at about twice the speed.

I have not done any design work on my radiator set up, I know it is going to be my biggest headache. Since I will be cowled, It will be a real job to put something together without creating a real "air brake" and still get good flow and velocitiy of the air.

Tony
 
Just a little follow up note, my first idea for a tubing beading tool did not work for $%%^^& and secondly don't waste you money on those tubing benders that look like coil springs, yes they will prevent a kink but not prevent serious distortion and flatening. Back to the drawing board on the tubing beader.

Tony
 
Sorry read the first 20 pages and then the last 6 and falling asleep!
What I do when changing the oil on my sleds is just drain the tank and change the filter.
I then refill the tank with new oil and pull the return hose coming from the engine base and oil cooler and put it into a jug
Start the engine and watch untill you see new oil coming out.
That way the engine always gets a good oil supply and your flush is complete.
Also hook your oil cooler between your tank and oil pump intake.
That lets the oil from the sump pumps degas in the tank.
The snowmobile setup is flawed with the cooler plumbed before the tank as it condenses unburnt gasoline and moisture before it gets to the tank.
Hope that helps!
I have 2 of these machines and so far are 100% reliable.
Cant wait to see one flying
On a side note I also have a 1000 Skidoo rated at 175 horse same year as the Polaris turbos.
How come the two turbos can go past that sled when they only have 145 rated horse?
I dont know if it is the 4 stroke thing or the turbo thing or the torque but there is a big difference more so up on top end.
the 2 strokes seem to fall on their nose on top end and also seem to fail most often in that mode.
The Weber seems to have proved itself in both watercraft and snowmobile markets in WOT use
Factory setups are working very well and reprograming stock computers is also working very well for those racing.
Some are getting over 200 horse with no failures
Something to think about!
 
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