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OSX - I believe it's a .40 or .46, sputters and raw fuel comes out of the muffler

by Larry Launstein Jr
(Flushing, Michigan)

I have an OS-X engine (an older one with both high speed and low speed needles. I believe it's a .40 or .46 engine. It sputters and slowly loses power and ultimately dies and cannot be started again.

I have also noticed raw fuel coming out of the muffler. One of the guys in our club had it going for awhile, but it is still doing this. And we've had problems getting the engine to respond when using high-speed needle. How can it be fixed, and if there are any illustrations you can provide on this forum, please do so.

Comments for OSX - I believe it's a .40 or .46, sputters and raw fuel comes out of the muffler

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check for leaks
by: rcdude07

Sounds like you know the symptom of the issue - raw fuel spitting out of the muffler. Check for pits/grooves in the head, any broken/missing gaskets, rust on bearings, etc...

I found out that it was the high-speed needle valve, but ...
by: Larry Launstein Jr

I took it to a nearby hobby shop, and the owner found that it was the high-speed needle valve. It has stopped flooding out and the raw fuel doesn't come out of the muffler anymore. However, I found out that the engine will not work unless I have a long-nosed glow plug with idlebars and is hot, or at least a long-nosed glow plug. And now that Fox is no longer in business, I need to find someone who makes and/or sells a plug like that. Our guys run 10%-15% glow fuel as I do. my engine has been misfiring a little bit.

by: Anonymous

Hi, you're probably running it too Rich. These little two strikes like less fuel. Try the high speed jet at 1 1/2 to 1 1/4 turns out, anymore than that it will be too rich and pump raw fuel straight out of the exhaust port.

I agree with everyone - it was the needle and running rich
by: Larry Launstein Jr

I would like to thank everybody for their assistance. It was both the needle and running too rich. However, the plane crashed not too long afterwrd.

I'm now attending Marshall University in Huntington, West Virginia.

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