davek

Sounds like you should fly the second engine and use the first engine for parts.

w8ye

My Feedback: (16)

Use the middle of the needle valve as your tank location key point no matter which way the engine is mounted

JollyPopper

My Feedback: (6)

Sean, did you do the crock pot thing? If so, how did it turn out? Also, you mention in a few posts back that the engine is mounted on its side. I assume it is in an airplane rather than a test stand. If so, when breaking in the newer engine, you might want to run it very rich and without a cowl for awhile. These things seem to be really susceptible to overheating. I believe that is what happened to mine and looking at the picture of your liner from the first engine, it may be what happened to yours.

Redwulf__34

Hi Jolly,
I've not crock potted it yet. When I saw how new the one I received was I put that on hold. But I will probably do it at some point. I've got a few other engines I would like to clean up this way. This one would be a good first run to see what to expect.

The engine is on an Ugly Stick. No Cowl.

Sean

JollyPopper

My Feedback: (6)

Looks like a winner. Good combination.

Redwulf__34

Ok! Well, at least I got the new engine to run long enough for the club president to sign off on me! Even though the flight was short, I guess cross wind dead stick landings with the full stop only a few yards away helps. I'm thinking of changing my log in name to Deadstick! With these darn OS engines I seem to do a lot of it!

OK, heres what is going on. She seems to run full throttle ok for as long as I want. However when I bring it back down to idle it will run smoothly for a while.....but then when I power back up she shuts down. This is pretty consistent. I started the engine and worked the throttle....it had good response.........I let it sit at idle for a while (2 min or more) then throttle up...shut down.......fire it back up.....throttle up and she will run as long as I want.........back to idle........runs for a while.....throttle up shut down.....now when it shuts down and I fire it back up...she acts flooded...it will kick back and even run a second backward then kick back forward.........

The air bleed is adjusted according to the manual....... I'm totally at a loss. Very frustrated too. I don't want to go out and buy a new .60 size engine. I'm getting back into this after a long long time off. I want to go into 1/4 scale gas engines with my next build and on. So I dont' want to spend $$$ on another .60 glow..........This really seems like a carb problem.. I think the first thing I'll try is the carb from my motor. My motor acted differently than this one. HOwever when Idleing this one is spitting fuel from the carb too. Doesn't seem to do it when running wide open.....................

MILDBILL-RCU

My Feedback: (6)

You say the low speed airbleed is adjusted to the manual. That is just a piont at which the eng. will run, but it needs to be adjusted to the engines needs from THAT setting. Let it idle for your 1-2 minutes, then pinch the fuel line at the carb & how long the engine runs will tell you which way to adjust the airbleed screw. If it shuts off within a second or two, then it is running lean at idle & the screw needs turned in to close off more air so it will pull more fuel while at idle. If it runs for 8-10 seconds or longer & rises in rpms while running, then idle air bleed needs to be turned out to allow more air in to the mix. Really what its doing is adjusting the pulling strength that the vacuum has on the fuel at the venturie by turning that screw. Good luck. Bill

Redwulf__34

Thanks Bill, I could try that. The method the manual says to use is to adjust the high speed first (obviously). Then on idle point the nose up about 15 degrees.....if it increases in RPM then it's to open the airbleed.......if the engine shuts off then close the bleed. It says it should run consistent and smooth with the nose up 15 degrees or so. And she runs very very smooth with the nose up on idle. No increase or roughness.

I could try your method. I should have thought about that at the field. Do you think the nose up method is sufficient? The reason I dont' suspect the air bleed is that it's not a consistent problem...it seems to only shut down on throttle up after she has run a while.

I should have mentioned the engine temp. After the 5 minute or so flight (mostly all 3/4 thottle) as soon as she came down I felt the engine and she was nice and cool.....I could squeeze it for all I had and it didn't burn me. It was warm but not scalding hot.

Sean

bubba153

It's been a long time since I've tuned an air-bleed carb, but from what you tell us, I think your idle mixture is too rich but I'll bet it's an idle mixture problem, in any case. The pinch test previously mentioned will go a long ways towards diagnosing the problem. I can't remember how sensitive the air-bleed screws are, but with a regular low-speed needle, in some engines, as little as a 10-degree turn will make the difference between being spot-on and stumbling/stopping when the throttle is advanced. Remember that the "idle" mixture doesn't just affect the idle, but rather the lower 30-50 percent of the throttle range. I'm guessing that the idle mixture is rich, and the engine is loading up at idle and then flooding out when you throttle it up (and if it stumbles prior to shutting down, I'm almost certain of this). If if simply STOPS as you throttle up, you are probably lean on the idle mixture. Unlike a regular LSN, airbleeds richen as you screw in, and lean as you screw out. SMALLSTEPS when changing the LSN, and the air-bleed, as well (yes, I realize you don't have a LSN). It's not uncommon for engines to spit small amounts of fuel from the carb at low speeds, but it sounds like yours is spitting an excessive amount, which also suggests a rich condition to me. As someone else mentioned, factory settings are just starting points where the engine can usually be encouraged to start, but not necessarily run well. General rule is to first adjust the HSN, as you have, then tune the LSN (or air-bleed), then you may need to re-adjust the HSN, and if you do, you may need a final (very minor) tweak to the LSN. When tuning the air-bleed, you aren't just looking for idle performance, but also performance in the transition in the lower 1/3-1/2 of the throttle.

Redwulf__34

Thanks for that info Bubba. I'll head over to the field Friday night and try Bills method. Your description is dead on with whats happening. I really feel like it's flooding out when I advance the throttle. The fuel doesn't just "spit" it will actually start running out the carb on idle. As far as how sensitive is the air bleed.. The manual says when adjusting to go half turns. I'll try 1/4 turns with it.

The carb is held on by two screws that go through the carb. Any chance air leaks in around them?

Thanks everyone! The little bit I did get to fly, the engine is going to do a nice job with this plane if I can get it to run..

Sean

big max 1935

My Feedback: (9)

If you have the air bleed screw out far enough not to be able to see any threads in the hole & it is still spitting raw fuel out of the carb you can try adjusting the travel so you can see a small opening in the venturi, this will give it more air. This worked on my old Enya engines . I have heard of some drilling out the air bleed hole to the next larger size but I hate to mess up a carb. If you work with it long enough it will run right . Max H.

PME

My Feedback: (6)

Sean:
Glad to hear it was not all me on this darn problem.
Roy

Redwulf__34

HI Roy,
Nope, wasnt you! This one has similar issues to mine but slightly different. I think the source is the same. I didn't make it to the field last night to mess with it. Cooking mine in the crock pot now!

Sean

Roby

I didn't read all the threads but I'll tell you about my experience with a friends OS .60 FP.

One day a long time ago a flying buddy bought a new .60FP and put it on his 4star 60.
He had a problem getting it to run correctly and asked me for some help. I tryed
every trick in the book trying to get this motor to run reasonably well enough so it
could be used. No matter what we did , nothing worked. It came to the point that I
took the motor home and dis assembled it looking for something,anything that would
cause a problem. I'll bet that I took that motor apart at least 6 times . By the time I
was done, every gasket had been sealed with RTV to insure no air leaks, the glow
plug was replaced , different fuel tried, and the tank location changed . (test stand)

Finally I gave up, no matter what I did it changed nothing. He put that motor back
in the box and shelved it.

To this day that .60 FP is the only motor that I was never able to figure out how to get
it to run correctly.

Regards,
Roby

Redwulf__34

Geeze Roby! That's not very encouraging! [&o]

Anyway, I'm close to that point too. Our fall field times have started today so I can't fly after 3:00 PM here. Bummer. I plan to try Saturday morning again. If I fail then I'll try on last thing, opening the air bleed hole one drill size. If that doesn't work, I'll sell them for parts on ebay and try to get a muffler for my Super Tigre. Anyone have one laying around??????

Sean

JollyPopper

My Feedback: (6)

Sean, your Super Tigre. What are the measurements between the mounting holes and is the muffler mounting holes threaded or is the engine case threaded? What size is the engine?

Redwulf__34

Looks to be about 47mm center to center. I'm not sure what model it is anymore. I bought it new in the mid 80's. It was a schneurle ported ABC engine is all I remember. I still have the box and manual but no where does it list a model. It's a .61. The muffler is to be threaded. It's a bolt through.

Think you have something???

I've been saving it to put on my mustang. I'll need some type of custom in cowl muffler for it then. So I didn't want to spend money on a muffler I wouldn't be using long.

Sean

JollyPopper

My Feedback: (6)

I'll be going out to the shop in a few minutes and I will check.

JollyPopper

My Feedback: (6)

Sorry Sean. The closest thing I have is 42mm, I believe they are for .60 size OS engines.

Redwulf__34

Here's the report!
Saturday morning I had hoped to get out before the wind picked up. I used your method of testing the air bleed and found it was definitely rich. when I started the air bleed was at about the half way point. It took one full turn out and she ran at idle awesome. It will sit and idle like a purring kitten now.

The wind had picked up really bad and was blowing crosswind. We have the remnants of Earl here I guess. Wind is blowing now about 17-20 consistent. I did a "brave" thing and took off! I feel lucky to have the bird back alive! So I ran two tanks of fuel through her on the ground. I'm not sure I trust it.

On the high speed side she seems inconsistent. It almost seems as if it won't lean out. This is really weird but it seems to get richer as the tank empties. When adjusting the high speed it seems like it doesn't lean out right. It never clearly changes sound/pitch. It sounds rich rich rich, then just cuts out as you lean the needle. When I adjusted the air bleed I had the high speed where i thought it was slightly rich not much.

I don't know how well I really trust it. But she'll idle forever now. And she throttles right up. All that is now good. It just seems like the high speed may cut out at any moment. Ideas??????? If the wind drops out in the next few days I'll get some flights on her.

Sean

w8ye

My Feedback: (16)

This sounds like bad fuel

Johnkpap

The fact that you have Idle and no cutting is Good News

I would try reducing the prop size or use a lighter prop, the the other option is the replacement engine may have not done
enough work to run in.

Fly the plane and see if things improve:- then reduce the prop size if req.

Good Luck

Johnkpap

Redwulf__34

Hope the fuel isn't bad. It's a new gallon. Anyone ever seen it bad right off the shelf? The hobby shop didn't have it. I had to wait a few days for it to come in. So I know it didn't sit around the store long.

Prop could be it. I had taken a chunk out of my 11X7 the last time up. So I had to put on my 12X6. It was all I had and she is old and heavy. Circa 1985!! I picked up a Master Airscrew 11X7. We'll see if that does it. Hope so!

You wouldn't believe how nice she idles. I had it down so slow you could almost count the revolutions by eye! And she would run there all day. Winds are supposed to die down. I'll get the smaller prop and give her a shot.

Sean

w8ye

My Feedback: (16)

The FP usually does well with a 12 X 6

da Rock

Try a couple of different plugs.

Make sure you adjust your highspeed needle valve. Now that you've changed the airbleed it's seeing a different amount of air available the entire throttle movement.

Also, sometimes when the top end has lost a bit of power it's from a small leak that's cropped up. Check all the bolts and look around all the seams for signs of leakage.

Trying the different plugs is a way to change the timing. Sometimes the original doesn't suit your altitude or fuel or age of the engine.