Motorcycle Repair: tw200, marvel mystery oil, valve clearance


Question
Hey Wayne I just ended up with a TW200 on a trade for some work I performed.  It's been sitting for about 8 years in a shop.  Only has 200 miles on it, looks brand new.  Anyway, of course it wouldn't start just with fresh gas.  I went through the carb and cleaned thoroughly.  Re installed and fired right up but would not run right and started smelling oil.  When I killed it oil is coming out of air inlet.  Stuck rings??? Any quick fixes like marvel mystery oil in cylinder? Thanks

Answer
Hi Rick,

Have you checked the compression that might tell you if the rings are stuck.
Also make sure the oil level is not too high in the site window.

Check the air filter as they are sometimes foam elements coated with oil,
the element might be over oiled.

The engine breather may be connected to the air box and
excessive ring blowby might end up in the intake making
it oily.

An engine pressure test will tell if an engine is leaking
past the valves or rings but takes some gauges and
fittings to accomplish.

Be very careful with the fuel tank and the fuel as old gas varnish
in the tank can plug up the carb quickly, like in a few minutes.

Use a small fuel filter for sure and you can clean the tank
with hydrochloric toilet bowl cleaner to remove old gas varnish
and gum.

I just worked for a week on an old bike where the fuel just
kept getting contaminated by the old fuel goo in the tank.
Finally got it clean and fresh gas too.

Pour a 1/2 cup of Marvel in the cylinder and let it sit
overnight. Turn it over with a rag to catch the excess oil.
Start it up, warm the engine up and see if it starts to improve.
If not, do it again. Finally, change your oil/filter and
take it for a long run if it seems to be running better.

Valve clearance might need checking too.

Let me know if you find out what's happening or need more info.

WS
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