Your LJ Smokes Constantly?
Posted: Wed May 23, 2007 7:54 pm
It's old enough to smoke, let it... 
Most of the time it is the check valves in the oil lines, they get clogged open due to dirty oil and/or sitting too long.
If the check valve is stuck open the oil can and will siphon through the pump and into the engine causing excessive smoke at startup. Of course all 2 strokes will smoke at startup but if it keeps on smoking for a long time you may have a check valve problem.
Each oil line has a check valve so on the compression stroke it won't push the oil back into the oil pump and in turns helps it to meter the amount of oil going into the jug on the down stroke.
Also I have found that a loose oil line "banjo" bolt will cause excessive smoke, and or a bad banjo gasket/washer.
Most of the time it is the check valves in the oil lines, they get clogged open due to dirty oil and/or sitting too long.
If the check valve is stuck open the oil can and will siphon through the pump and into the engine causing excessive smoke at startup. Of course all 2 strokes will smoke at startup but if it keeps on smoking for a long time you may have a check valve problem.
Each oil line has a check valve so on the compression stroke it won't push the oil back into the oil pump and in turns helps it to meter the amount of oil going into the jug on the down stroke.
Also I have found that a loose oil line "banjo" bolt will cause excessive smoke, and or a bad banjo gasket/washer.