Probs with OS 32 engine

[paul b]

Hi folks, I have a bit of a prob with my os 32 engine on a Caliber 30 heli.
It starts fine with plenty of oil and smoke coming out of muffler, but when I disconnect the glow plug the engine dies. I'Ve no idea where to start, I've leaned out the mixture screw from 2 turns to 1.5 turns to 1 turn with no joy, the engine still cuts out when plug is taken off. the response from radio is good, it revs up fine with plug on. Any help would be a great help.

Cheers...P

[z11355]

replace the plug, it's dying.

[WayneBrown]

I think the plug is dead..

[paul b]

Hi guys, I've changed the plug twice, both OS#8 plugs with a 15% nitro mix. Could it be that the little mixture screw in the throttle barrel is set to rich..?

[paul b]

I was lookiing at a thread about a pinch test.The pinch test can reveal most of the idle issues.
Let your engine idle for a few seconds (with your problems you might need a permanent connected glowplug).
Pinch the fuel line as close to the intake of the carb as possible.
This way you will stop the engine, but the most important thing to do is listen to the sound when you do this. It should rev up after a second or 3 to 5 and than stop. If it immediately stops it is too lean, if it takes more than say 8 seconds to stop(or rev up) it is too rich. If the revs don't pick up it is also too lean.

When I did the pinch test it reved up for 3-5 secs then died with the glow plug attached.but when i removed the new glow plug it damn thing died again on me....

does this mean that the little idle mixture screw in th ethrottle barrell is set right...? :roll: :dontknow

[paul b]

Hi guys, I've tried the pinch test, and it runs for about 3-5 secs before cutting on me with the glow plug OS#8 still connected.
It revs for a sec or 2 before cutting out.
I have also have the orginal OS manual and have set it to their instructions.
The engine isn't brand new. I had it running in this heli for 2-3 months, with no probs. Was sitting for a few months befrore I took it out again to fly...?

[WayneBrown]

could be trash in the carb, but the idle mixture sounds rich and sloppy too.
only adjust the idle mixture 1/16 of a turn at a time, that thing is REAL sensitive.
Check the head bolts and make sure they are tight.
Is there a rough feeling when turning the motor over by hand?

[paul b]

Hi Folks :arggg: , I've tried a new OS#8 straight out of packet,same prob.
But what I did do was lean out the litle idle mixture screw in throttle barrel a half turn, and it ran for a while with glow plug disconnected. But when I increased the throttle on radio it cut out pretty quickly.

So I think I'm getting some where..lol
With some more tweaking I think I may getting it running somthly again...Hopefully

[paul b]

I was looking at a different post and by turning the idle mix screw half a turn is too much, so I'll set itt back a quater turn and see what happens.. :arggg: