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Dang engine!

Dang engine! My OS 75 two stroke. New OS #8 plug. Back flushed the carb.

Recently (with no crashes) this engine will NOT idle. The best I can get is an idle that varies between 4000 and 8000 RPM measured (Rum Rum Rum -- like a kid on a motorcycle). I have tried resetting the idle screw to no avail -- and I actually followed the directions in the manual.

My troubles began with the engine dying at low RPM like it was WAY too rich and the plug fire was being put out. This was before I fiddled with the mixture screw. After fiddeling the engine will -- sort of -- idle, see above.

Any ideas? New carb maybe (darn things are nor cheep)?

Thanks, Lee

Reply to
Lee B
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My best guess would be check for an airleak; most likeley around the front bearing. Apart from that is the carb sat tight to the crankcase and is it and all its fittings secure.

How old is the engine in gallons of fuel and are the bearings the original?

Reply to
Chris Dugan

Adjust the valves....

Reply to
Tom Minger

There are no "valves" to adjust on a two stroke I believe. :-)

Reply to
Vance

I agree. check all the usual suspects... Cracks in fuel lines - especially where they slide on the metal bits. Cracks in fuel tank. Clogged klunk or filter. Head gasket.

--Mark

Reply to
Mr. Eastman

Air leak?? Does that include a missing screw that was supposed to lock the carb to the engine body -- and created an EXTRA air hole??? Engine was side mounted with the missing screw on the bottom side where I did not see it until I took the carb off for cleaning!!

Thanks guys

Reply to
Lee B

Doh............

Read once for jist; read twice to get all the words right.

Err..........don't try to adjust the valves :-)

Reply to
Tom Minger

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