Hi Bax,
I have recently come into an older OS Gemini FT160 with the older style bleed air carb. Unfortunately the previous owner had done a poor job of storage and I assume he had been using castor fuel , so the engine was really gummed up , to the point where the carb barrel would not move.
I soaked the engine for several days in fuel and all appears to be back to normal. I have run the engine and it seems to run fine.
Unfortunately I removed the high speed needle as well as the low speed bleed air screw without being able to record the setting due to them being gummed up.
What I would like to know is what is the setting for the high speed needle ( turns open from closed position ) and the setting for the low air bleed screw ( turns open from full close )
The engine from the original owner had been run in as well as some flying time on it as well.
The engine seems to be putting out excessive " slime " as well as smoking when throttle advanced from idle . Seems fine at high RPM , so I would assume this might be a low speed loading problem. I have on board glo system so both cylinders are firing at low RPM.
There seems to be quite a bit of fuel coming out of the crankcase vent , but I have heard that this is quite normal for this engine.
Sorry for so many questions
Regards, Jim

Hi Jim I have an engine like yours, and mine has the following settings:
main needle is 1 3/4 turns open from the closed position, and idle air bleed 8 1/2 turns from the closed position

I have good quantity of oil leaking from the crankcase and no slime or smoke from the exhaust stacks

hope this helps

Thanks Don, I will give your settings a try, much appreciated, Regards, Jim

Hi Don,
I just tried the settings that you mentioned. I basically had the 1 3/4 turns out from closed on the high speed needle already.
Can you confirm that the low speed bleed setting is 8 1/2 FULL turns out from closed, that seemes to be a lot. Did you mean 1/2 turns which would make it about 4 1/4 Full turns. It is too late to run the engine tonight but I will try in the morning.
Thanks, Jim

I've got a twin 160 that I'm having problems with a cylinder dropping when I fly, it's always the same cylinder. It starts fine and runs up fine, but once it's in the air one cylinder guits running. I've tried leaning it out as I thought it may be too rich and flooding out the cylinder and I've also changed glow plugs, any idea why this continues to happen?
Thanks,
Val

Four-stroke engines tend to run a bit better if you're using fuel with all-synthetic or mostly-synthetic oils. That's because castor will tend to varnish and gum. If you disassemble your engine a few times per season, it's not a problem, otherwise go with lower-castor oil content fuels. That also means you'll have to flood your engine with oil at the end of the day to prevent rust.

For the O.S. FT-160 twin-cylinder engine, you should start out with the high-speed needle at about 2-1/2 to 3 turns out from closed. That's a very rich setting, but is a good starting point. The air-bleed screw should be set so that it blocks the air-bleed hole 1/2 way across. Start the engine at a part throttle and advance it to full. Then get the high-speed needle set. If one cylinder is leaner than the other, set the engine to the lean cylinder. Once the top-end is set, you can adjust the idle.

The air-bleed screw works opposite to a needle valve. You turn it clockwise to richen the idle mixture, and counter-clockwise to lean the idle mixture. The FT-160 should be able to be set so that you get an excellent idle.

If one cylinder tends to quit at a reduced throttle setting, but not at a true idle, or one cylinder won't idle for very long, then you may have an ignition problem. Use brand-new O.S. Type F glow plugs. If new plugs don't work, try adding an ignition battery to the plugs that will heat them when the throttle is below 1/4 or 1/3. A last resort would be replacement of the piston rings, cylinder liners, pistons, or all three. Bad compression will keep any engine from idling well.

Thanks Bax,
Do you know how many turns from closed the bleed air screw should be turned out to attain the desired position. It is quite difficult to see without removing the carb. I thought that I had it about mid way in the hole with about 4 1/4 turns out from full closed, however at this setting it was still emitting a lot of " slime " over the aircraft and smoke at throttle up. The grass had quite a bit of unburned fuel and oily residue on it also.
Another fellow who answered on this this thread said he had set his bleed screw at 8 1/2 turns from full closed position. I don't know if this was in error or if he meant 8 1/2 half turns, it seems a little excessive. Still awaiting conformation from him.
However he said that it gave no " slime " and no smoke at that setting
Thanks, Jim

Hi Jim, yes, basically I have the air bleeding hole completely open, and I counted again and it was 8 and a half turns.
With this, I have good idle and good acceleration to full speed.

Regards
Hector

Hi Val, I once had a flame out of a cylinder, and this was due to my air bleed being to close, thus having the mixture too rich. I opened more the air bleed which solved my problem. I do not use in flight glow driver.

regards

Hector

Hi Hector,
Sorry I got your name wrong. I guess that I thought your location was your name.
I just wanted to confirm that the bleed was a full 8 1/2 turns before I try it again. If the Bleed hole is full open it does not appear that it does much. I see the OS recommendation is to have the bleed screw cover 1/2 of the bleed hole opening- this works out to be about 4 1/4 full turns out by my estimation, this is why I thought that maybe you were using 8 1/2 - half turns -which would have worked out to be 4 1/4 full turns - it was just a numerical coincidence.
I will give this a try again , At 4 1/4 turns I get quite a bit of smoke and oil residue when powering up, particularly from the left cylinder.
Thanks, Jim

Thanks Bax, I will give this a try.

No worries about my name.
a lot of smoke means a rich mixture, so I had it open completely and it worked fine to me... Hope it does the same in your case.
the numerical coincidence is very weird.... but it is a very good coincidence

What prop are you using???
I am using an APC 16x8 and using powermaster 15%, glow plugs are both OS F

Good luck

Hector

Hi Hector,

Pouring rain up here so I havn't been able to do an engine run today

I am using a Xoar 16 x 8 wooden beech propeller
O.S. F glow plugs
Morgan Cool Power 100% Synthetic Fuel - 10% nitro content - 17% oil content

I use this fuel in my other 4 strokes without problems

Will try and run the engine tomorrow
Regards, Jim

Thanks Jim

Hope to hear good news tomorrow

hector

We don't have a specific number of turns for the air-bleed screw. We set it visually and go from there. If we don't know where it's set, we usually close it to make the idle at maximum rich. We then work it leaner from there.

To all: please be advised that THIS IS NOT A DISCUSSION FORUM. If you wish to post your own information or answer questions, then please do that in the general engines forum. This forum is for people to ask questions of the O.S. Service Staff and get answers from them. Do not answer other people's questions. If you have a follow-up question on the same topic as the thread starter, you may add your question. However, discussions or answers from non-O.S. Support people will be deleted.

Hello Bax,
I have an OS FT160 MAGNUM engine that I am putting in a TF Stinson Reliant. It fits fully inside the cowl. I have two questions, Are the exhaust pipes that come with the engine adequate or is there some type of muffler system I need to purchase. The second question is : if the pipes are adequate then are there some kind of extensions I can purchase to dump the exhaust outside the cowl? Thanks in advance Smitty

The exhaust pipes that come with your O.S. FT-160 are sufficient. You don't need to add anything. If you want them longer, you can easily make extensions by using copper tubing and hose clamps.

Hi Bax, I had to dissasemble my FT 106 to free stuck cam followers. I am now putting it back together. My question concerns the cam timing. do I align, what appears to be a timing mark on the back of the crankshaft with the hole in the camshaft gear , so they point at each other?.

Thanks,

Skip

The hole in one gear and the dot on the other must line up in the center on a straight line between the centers of the crankshaft and camshaft.

Thanks Bax.


Skip