Speedzilla Forums banner

1 - 4 of 4 Posts

·
Registered
Joined
·
132 Posts
Discussion Starter #1
My SM610 is blowing a huge amount of oil into the airbox. I almost crashed because it oiled the side of the tire. It was my first ride after reinstalling the engine after having the case welded up from chain damage. The engine was not disassembled. It was not overfilled with oil-I added the correct volume of oil and the sight glass confirmed this. The engine starts, idles, and runs normally and I ran it at relatively low rpm and throttle openings because I was warming it up.

As far as I can tell, everything is hooked up correctly, hoses going where the illustrations indicate in the manual. I don't think there is anything wrong with the engine that would cause excessive crankcase pressure.

What could I have done wrong to cause this. Could a plugged hose cause this? I don't see how, but I'm grasping at straws.
 

·
Registered
Joined
·
257 Posts
when you had to engine out was it tipped on its sides,if so you probably had oil going in places it wouldnt usually go.
thus causing oil to end up in the air box
or you got a vent hose wrong. :wtf
 

·
Registered
Joined
·
132 Posts
Discussion Starter #3
The oil was drained before the engine was removed. The hose lengths are such that they will only fit in one place, and that agrees with the assembly illustrations.
 

·
Registered
Joined
·
132 Posts
Discussion Starter #4 (Edited)
Best info is that it's the reed valve, taken out by a worn timing chain. A serious problem on lots of 610s. Do a search.

I haven't taken mine apart yet to confirm.

Update - timing chain probably worn, but didn't touch reed valve. George says reed valve couldn't cause this problem.
 
1 - 4 of 4 Posts
Top