two stroke engines leak a little oil?

B

bigbutterbean

Active Member
i have had 4 of these two stroke engines, and all of them have leaked small amounts of burnt oil from the top of the head. not sure exactly where it comes from, but seems it comes from the spark plug hole. its only a small amount, not more than a few drops. is this normal?
 
Even a small amount is not normal as long as things are sealed and tight. The spark plug, head gasket, exhaust manifold are all places that can leak...but shouldn't. Does your spark plug have a gasket? They're usually a metal band that crushes and seals if the plug is torqued properly.

The kit supplied exhaust manifold gasket is notorious for going bad prematurely. Replace it with gasket material made for exhaust available at all auto parts stores.
If you're using the chrome acorn nuts on the cylinder head there is the potential for them to bottom out before they are tight against the head which can allow the head gasket to leak. Replace them with shouldered hex nuts and lock washers and torque them to 110 to 120 inch pounds.
Tom
 
I never had a problem with a muffler gasket leaking. My head gasket isn't leaking either. The oil just pools on top of the head near the spark plug hole. Yeah, my spark plug has a metal gasket. I have it in there fairly tight, I didn't want to overtighten for the fear of stripping threads. Are you saying I should tighten it till it stops?
 
80 to 100 inch pounds should be sufficient to seal the plug. Torque it cold then after the engine has reached operating temperature a couple of times 'CHECK' the torque again. If it hasn't changed you're good to go. If it has loosened any retorque to the 80 to 100 inch pounds. You shouldn't have any problems afterwards.

You might want to check the head sealing surface where the plug seats against it. Look for any nicks or gouges that could keep the plug's gasket from sealing.
Good luck.
Tom
 
I don't know if I can fit my torque wrench between my engine and the top bar of my frame, but I will try. I have been using a spark plug socket that a buddy gave me, because I am using an ngk spark plug and the kit supplied spark plug tool doesn't fit on the ngk plug. So I usually tighten the plug using the spark plug socket and an adjustable wrench.
 
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