I have an OS32 in a heli I havent started in 4 years. Started last week and it ran fine for a full tank. Now it won't stay on with glow starter removed. I have tried 3 new plugs and have tried leaning out carb. Again it ran fine first time with carb settings from 4 years ago which always ran fine. I am at a loss. Could engine be shot from sitting for so long?

Have you pulled the carb and spray bar to see if it is partially clogged?

Ottodude

No, the engine should not be "shot" from sitting for long. As long as its clean it should work. The fact that the engine did start and did run for a tank indicates its ok.

If it will run with the glow plug starter on but not off then the needle settings could be too rich - the excess fuel smothers the glow plug which can only keep burning if you leave the glow starter on.

How long are you trying to idle this engine? These engines generally do not idle well for more than about 1 minute then they start spluttering as they fill with fuel.

Start the engine and then crank it up about 1/2 way to let it warm up. Then remove the glow starter and see if it still works.

If it still acts funny, you probably need to strip and clean it.

If it then still acts funny, you probably need to have it looked at by O/S.

My 2c

Is your fuel 4 years old too????

Bad fuel causes this and will mess up a new plug until it's run for a while on some fresh stuff.

Kirk