burnig up plugs OS 50

[choppaholic]

Think there is a few things to do
It's over reving
might need the fuel line changing in the tank ( the clunk ) that's the think you hear when moving the heli around clunk clunk

I would get a governor for christmas

ha! now i get it

i have a governor but no 7 channel Tx as of yet, thats what i am getting for chritmas .

the clunk is moving about the tank when i invert it it is getting down as well.

i will lower the curve tomorrow and give it another go tomorrow before i do an engine out. i am on a 4 week holiday so loads of time .

[Jamin_00]

I have heard before of the tank having a split in it causing it to lean out once the fuel drops below a certain level.

So that would suggest an engine problem then??

[David Drew]

Another thing that can blow plugs is duff fuel & clunk lines.

Small bits of it can get into the engine & smash a plug.

I change all mine every two months or so.

David

[choppaholic]

so after doing a few changes,

New header tank,
OS bubble less Clunk,
all new fuel line filter.

i head to the filed, give it a start, to small firings and i loose full compression, the starter was spinning away with no resistance from the engine, quick check to see oneway bearing ok? yes....
so i pack up head home engine out and see whats been causing my plugs to go.

so guys any advice please,
i think my engine serioulsy over reved overheated etc... etc...

is it worth putting a new piston and ring to see if it will work or bin it, a new sleeve and its definitely the bin due to the sleeve price....the sleeve seems good but you never know until it will fire up.

i do have spare engine so please advice so i dont do this again.

Cheers

Sav

[Rctintin]

Is that a hole in your piston?

[Geek]

Sorry to hear this.
Think I would strip it and check bearings as it might be bearing that has done the damage. You might find that there are still alot of spares to be had from that engine
then it's up to you about cost of rebuild or new or secondhand.
All the best

[Dedcalm]

so after doing a few changes,

New header tank,
OS bubble less Clunk,
all new fuel line filter.

i head to the filed, give it a start, to small firings and i loose full compression, the starter was spinning away with no resistance from the engine, quick check to see oneway bearing ok? yes....
so i pack up head home engine out and see whats been causing my plugs to go.

so guys any advice please,
i think my engine serioulsy over reved overheated etc... etc...

is it worth putting a new piston and ring to see if it will work or bin it, a new sleeve and its definitely the bin due to the sleeve price....the sleeve seems good but you never know until it will fire up.

i do have spare engine so please advice so i dont do this again.

Cheers

Sav

Looks like a wacking great hole in your piston... that would account for your lack of compression.

[Rotorhead]

I had that happen on an old OS50 SH-X, though it was about two years old and had well over 150 flights on it, mainly mild aerobatics and some 3D.

Like a lot of people have said that mid point on the throttle curve is way too high especially since you're not running a governor, it needs to be about 30-40% depending on the blades/heli mechanics etc, just enough to maintain headspeed at zero pitch, 80% is more like an electric throttle curve.

Like Geek said, strip down the engine, and make sure there are no bits left at all in the engine, the last thing you want is to put a new piston, liner and ring in and have it all get scored.

[choppaholic]

Is that a hole in your piston?

yes its a piston melt down

[choppaholic]

it needs to be about 30-40% depending on the blades/heli mechanics etc, just enough to maintain headspeed at zero pitch, 80% is more like an electric throttle curve.
.

yes i went from an electric to nitro so thought it would be the same theory, quite an expensive way to find out not..

when you say 30-40% do actaly mean 40% max in idel up?

thanks a lot guys

[Rotorhead]

In either Idle 1 or 2 when the pitch is at zero degrees (midstick on a 3D pitch curve), you want roughly 30-40% on the throttle curve.

Mine is like this on my Evo 50

Pitch ____Throttle

+100_____100
+56______72.5
+27______50
0________40
-27______50
-56______72.5
-100_____100

Obviously 7 point curves, the pitch curve corresponds to +100 = full pitch, 0 = zero pitch, -100 full negative pitch.