OS32 bogging down

Been using the same OS32 for over 7 years (ringed head- they don't make them like that anymore!!), not had many problems.

Right now I'm fighting with a bogging down problem. When I go full throttle/full pitch the engine bogs down really bad and often times never recovers until the pitch is brought down to nearly nothing.

Any ideas? Anywhere else in the throttle range is perfect, just seems to be the really high end. Could it be too much pitch? Too rich a needle setting?

Thanks.

You said you've been using the same engine for 7 years? Is this without a rebuild? Do you have a lot of hours on it. I'm new to heli flying, but not to R/C ing, and it sounds like a tired engine. When a tired engine gets hot, it loses compression and hence the bogging down. If it is the case that you've been using the same engine all this time, it might be time for a new one, or rebuild it. Hope this helps.

Interesting thought. There are a lot of hours on it. It is a ringed head (relying on a ring on the piston for a seal as opposed to the normal friction seal on newer engines).

It is very strong for the most part but at full pitch it just can't handle it.

I'm going to do some testing this weekend with the carb and see if the mixture has anything to do with it.

Also depends a lot on the fuel, whether its left for any length of time with fule residue in it

What plug you using? Enya3 or OS8 ar probably the best ones, cool power 10% will make a difference

Chris

Hmmm, the fuel is always fresh, i do about a gallon a month.

I don't know about the plugs, they're pretty old (in good condition) and I don't remember the rating.

hi jhp

a tired sleve ,piston and ring sounds right for lost of compression at high end ,then also to much pitch but if like you said flying 7 years with these settings and no prob then somthing else could be wrong,could be simple things like a cloged pressure niple or fuel filter,if you have more vibrations then before (air bubbles in fuel tank)fuel lines could need a change try streching them to see if they crack or have holes in them.
comming back to the pich thing if your flying more agressive then before your engine is probably just overheating and your theory of mixture could do the trick .
do you have more then +9 at high end usualy more then this puts to much load on the blades .one way to check if you have to much pitch try modifying the throtle curve so you have more power at 75 % so when you get at full ,your blades will be up to speed and wont be under power at full.

let me know how things go

steff

Not sure about the pitch. It's probably 10 or more. The last time I had money to get a pitch measuring tool, no one in the state could get one.

I run a gov on it at about 1450 RPM (blade rpm) so it's trying to adjust automatically. I'll have to experiment with it off. I love the fact that I don't over rev any more when the wind gives extra lift...

cool let me know how that goes and as for a pitch gage
K&S makes a real good one and it's cheap as well.
if you have trouble getting one let me know i can get one and send it to you

steff