Idleing
 

I have a OS 40 fs I bought it from a friend he said he didn't use it much anyway I can't get it to idle without the trim almost all the the way up. the engine starts great and run vary good but can't get it to low idle. Can someone give me a idea that i migth try. I'm putting it on a LT25 trainer and would like to have it idle down when I'm trying to land.</p>

RE: Idleing
 

Read this thread:

http://www.rcuniverse.com/forum/m_88..._1/key_/tm.htm

RE: Idleing
 

The thread Joe started was on his YS 1.10 when he couldn't get it to idle. There is a forum for glow engines and there is factory support for OS. If you go into the glow engine forum there are step by step instructions on how to tune your FS and if you can't find any {there are bnches} then you can ask Bill Baxtor at factory support. How to tune a FS is pretty much the same as a two stroke as far as the needles go but you can run into other problems like valves and glow plugs. Go look or ask Bill.;)

RE: Idleing
 

How high is it idling? If it won't pull the plane sitting flat, then it's probably low enough to do landings.

RE: Idleing
 

Do you mean the engine dies from idling too slow, if you pull the throttle stick back? That's my interpretation of your first statement. Your last statement could be interpreted to say the engine runs too fast when you are trying to land.

Either way, I think you need to get familiar with (1) mechanical linkage adjustment and (2) engine idle screw adjustment. There are "Sticky" posts at the top of the Beginners forum which address those, and a lot of other things valuable to the beginning flyer.

Good luck,
Dave Olson

RE: Idleing
 

My first thought is about the same as Dave's.
It assumes the engine idles fine at the speed you want but the trim lever is not centered.
The throttle pushrod needs to be slightly longer or shorter so you can have the trim fairly centered when it is idling at the speed you want.

Carrell

RE: Idleing
 

I have the same motor. I have it in my Avistar Trainer. I originally used power master 15% and had a heck of a time trying to get it to idle. I switched to my Heli Fuel Cool Power 15% and it idles and holds at 2700rpm. Yesterday a buddy of mine said to try 20% or even 30% Heli fuel. I tried some of his 20% Cool Power Heli fuel and it held a constant 2500rpm. I have the needles set richer cuz of the higher nitro %. But, if trying different fuel is not an option you can try my setting. The low needle - after you turn it completely clockwise until it stops - I have it turned out 1/4 turn. I think it's still rich but thats where it idles the best for my motor. I don't know what everyone uses but I like Heli fuel thats full synthetic. Less mess and hardly (practically none) any carbon build up inside or outside of the engine.

RE: Idleing
 

Well i fondly got it to idle and the trim setting is just under half way up it seams it wasn't the carb setting as much as the way i had the throttle wire it was in a bind as so as i turn it over that salved the problem . Anyway thank for the ideas and help.