My New Bensen w/Subaru

MMorgan

Gold Supporter
Joined
Nov 7, 2003
Messages
319
Location
Kaplan, LA.
Aircraft
Aviomania Sport, Bensen, Flight Design CTSW
Total Flight Time
4000+
As most of you probably know, me and Mike Gaspard went to North Carolina last week to get this Bensen from Ron Awad. After a day of rest and a few days of work catch up, we started tinkering over the weekend.

Of course I let the expert (Mike Gaspard) fly it first. It flew well and after a few adjustments I got in it to do some high speed taxi and crow hopping. The large all flying rudder was giving me a little trouble at first (it was flying me instead of me flying it). After several high speed runs I went around the pattern and it felt fine.

I actually had to add weight to the nose because at 155lbs the nose wheel will barely stay down. Will probably move the axle back an inch or two to compensate.

We developed a pretty major oil leak on the valve cover so I changed the gasket today and that is resolved. The water temp is running too high (210-220 degrees) so we flushed the cooling system and added fresh Prestone. I installed a new thermostat and after todays flight it is still too high. I bought a new radiator cap but they gave me the wrong one so I will try that tomorrow. There is no pressure when the cap is removed so I'm hoping that is the problem.

My initial impressions after three flights is I like the machine alot. It is a very different feel than the Air Command and there is no pod. It is much more stable with the horizontal stab in the propwash and being a heavier machine.
 
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Glad your liking it. You might check to make sure you didn't get a air bubble in the cooling system causing the hot temps. It is pretty common for the Subarus to get a air lock in the cooling system and that will cause lot's of problems. Also if you don't get pressure in the hoses after it it up to operating temps then that may cause a problem too. I only flew it twice and for short flights, I didn't have any problems. It did get up around 200 if I recall. Oh and some of the guys running the soobs will modify the thermostat or remove it completely to get their temps in line.

How do you like those blades? Smooth or what! and what about power, does it feel about the same as the 503 on your Aircommand?
 
Mike,
I know that machine well! It was built bolt for nut after my first machine. Bill Lipe built it and flew it for years,He is a world war two piolt,flew the heavy stuff,b25s mostly I believe. The all flying rudder was designed by me and Dennis Dennison of south Fla.The engine was the third subura to fly in the states. Don Bouchard #1 and Me #2. It is a good machine and hangered all of its life,don't know after it was bought from
Bill. I have flown the machine and found nothing bad about it. I'm sure you will have a lot of good times with it.
Bud O'Neal
 
Bud,

I talked to Bill tonight. He told me lots of good info on the machine. He said he sold it last year and I guess Ron bought it from the guy Bill sold it to.

Ron, the blades are smooth. I've only flown it three short flights but it appears it is very close to the 503.. today I was climbing a 50mph and it seemed to do much better than yesterday. My Air Command climbs well at 40mph. I'll know more specifics after I fly it a few more times. We bled the air out of the system but after every flight it is down a couple of inches in the filler tube so I'm not sure if all the air is out. I think the lack of pressure is the problem and hopefully the new cap will solve it. As a last resort I will remove the thermostat but I wanted to leave it in if possible.
 
It might be a bad cap and the coolant may be blowing out past the cap into the catch tank. The guy Bill sold the gyro to never flew it, he only ran it in the yard and taxied it up the street and back, He sold it to me. I was going to keep it cause for 4 grand why not right? But I needed the money to pay for Dominator parts to get it done. I am a little too heavy for the direct drive subaru, it will fly me but climb rate isn't real hot so I am glad you bought it weighing only 155 lbs, with you in it the performance should be pretty darn good.

I hope there isn't anything wrong with the engine besides a air bubble or a bad cap or pressure leak in the radiator or something, BUT the nice thing about a subaru is if the problems that crop up look like they will cost more than 2 or 3 hundred bucks to fix.... Then you just go to the junkyard and buy a " new " engine and swap out the old broken one. Matter of fact for 2 or 3 hundred bucks you can find a old Subaru car still on the road and yank out the engine and sell the rest of the car to the junkyard for parts and have almost nothing invested in the " new " engine! you can have that engine off and the new engine installed and running in about two hours. it is a very simple swap out since nothing has to be done to the inside of the engine.
 
Screw-In

I hope yall enjoy the gyro and work out any bugs it may have.

Ron, Gimmie your address and I'll send you some "As Is" stickers if you need them. I lost track but in the last month, how many gyros and aircraft as a hole have you bought, sold, kept.

I also have a computer program that will allow you to keep up with inventory and monitor profits and losses. :D

Just bustin your balls, you know I love ya.

Screw-Out
 
Installed a new rotor bearing yesterday along with new bolts, nuts and pins in the rotor head. Feels much smoother and quieter now.

Many thanks to Mike Gaspard for his valuable assistance.

Back to the cooling problem. Again, the eagle eye of Mike Gaspard noticed the neck of the filler tube was around an inch deep. The old cap and the new one I bought is only a half inch or so deep so the cap is not sealing. I went by one store late yesterday and they did not have any caps that are deeper. I will search some more to find one that seals. Not sure where this filler tube came from as most seem to have a shorter neck.

I feel this has been the problem of no pressure since we could find no other indicators of any leakage anywhere in the system.
 
Cooling problem update:

After several days of trying different things the temp is still running 210. I had a new neck soldered on the fill tube so the standard cap will seal. That had no effect on the temp. I removed the thermostat completely and still it runs the same temp. We retarded the timing and again no change. We are fairly certain there is no air in the system. Maybe it's just going to run at 210 no matter what. The manual says the elec fan kicks on at 208 if it was in an auto so maybe 210 is ok. It seems it's going to run there no matter what. About the only option left is the radiator...possibly old, corroded, etc and not cooling as it should.

We verified the temp with another gauge and they were within 5 degrees.

What are other direct drive Subaru's temps running????
 
mike my first gyro also direct drive sub ran at least that hot. Some folks say theirs run real cool. But not the ones I have dealt with.
 
Subaru water temp

Subaru water temp

My EA-81 was running on the hot side...210-220..when I first got it. I replaced the thermostat...a 180 degree one...it now runs right at 180-185, even in the summer. The autoparts guy said the old thermostat looked like it wasnt opening up completely...it was pretty corroded.
 
Mike,if your running a lean mixture it'll overheat.You could mount a truck radiater on it and it'll still run hot.[localised boiling]
Pull out a couple of plugs and check their colour,if they are light or white you are running too lean a mixture.

At the last flyin in Oz alot of machines were boiling because of lean mixture,the machines came from lower altitudes and the air in the center of Oz was upsett'n their fuel/air mixes.

If you'v tryed this already ,just tell me to shut up.
 
Is it an EA-81 or EJ-22? I assume you are using an 81. If you are using a EJ I can give you a few tips that I learned troubleshooting mine.
 
birdy said:
...At the last flyin in Oz alot of machines were boiling because of lean mixture,the machines came from lower altitudes and the air in the center of Oz was upsett'n their fuel/air mixes...

Engines that are set for low DA will run rich, not lean, when they fly at high DA. Their cooling systems may not be sized properly for the hotter climate of central Oz, though.

Mike – scaling in the cooling system may be part of the problem. If people have used tap water in the radiator the minerals will drop out in the engine block and radiator and interfere with heat transfer (same happens in the water heater). If this is the case you may want to flush the system with some de-scaling liquid.

I have bought an aluminum radiator from Air Command for $100. This is an awesome radiator! It is light (aluminum and plastic), and VERY effective for cooling. I am afraid it is too effective for my 532.

Udi-
 
The engine is an EA-81. Except for the short time Ron had the machine, it's been in FL. and now in LA. so there hasn't been any changes in air density. I will check the plugs next time out to see what they look like.

Udi....Is that a new radiator for $100?? That's a good price. If you don't mind, what are the dimensions??

If yours is cooling too good how about a swap?? Just kidding.

Paul....One of the first things I did was put a new thermostat and there was no change. Even with it now completely out it just takes a little longer to get to 210.
 
Don't take the thermostat out. On some engines, The thermostat also acts as a restrictor to slow the coolant flow. If the coolant flows through the rad too fast it will not transfer the heat effectively and cause overheating. Try a new 180 and see if it helps, Thermostats are cheap.
 
MMorgan said:
...it's been in FL. and now in LA. so there hasn't been any changes in air density...

Udi....Is that a new radiator for $100?? That's a good price. If you don't mind, what are the dimensions??

The fuel mixture mostly affects the EGTs, not the coolant temp.

If you call Air Command (903) 527-3335 they can give you the exact dimensions. Mine is about 16x24 inch; I can measure when I get home. Yeh - I think $100 is a good price for a brand new radiator (a small consolation after the damage I inflicted on it Sunday..)!

Udi-
 
scottessex said:
Don't take the thermostat out. On some engines, The thermostat also acts as a restrictor to slow the coolant flow. If the coolant flows through the rad too fast it will not transfer the heat effectively and cause overheating. Try a new 180 and see if it helps, Thermostats are cheap.

Scott,

Mike (the other one) had already tried a new thermostat, and still had the same problem. We'll just have to flush out the cooling system, and see what happens.
 
Okay, I must have missed that. Good luck and let us know how it comes out.
 
One more thing to look into. If you know your cap is sealing good and tight, tie the gyro up and run it on the ground and look at the hose going into the overflow bottle. If you see airbubbles going through the hose into the overflow bottle then one of the head gaskets is going bad and that is the problem. Happened on my first gyro.

Sorry your having trouble with the engine Mike. I only had it for a couple weeks and only messed with it twice and for short hops around the patch. It didn't give me any trouble.
 
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