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plume of smoke coming from rocker

Posted: Thu Jan 07, 2010 4:15 pm
by andrew.searston
hi everyone
just a quick question
when my moggy is running their is a plume of smoke coming from the rocker breather constantly and the oil cap (when you take it off)
what do this mean????
is it just a worn engine???
thanks
andrew

Posted: Thu Jan 07, 2010 6:07 pm
by PSL184
Usually signifies that the crankcase pressure is being forced past the piston rings, so yes, worn bores.

Posted: Thu Jan 07, 2010 6:31 pm
by bmcecosse
Fraid so = worn engine. Slight haze would be nothing to worry (too much) about - but 'plume' suggests quite a lot ? It can be contained if you make sure the rocker breather is connected to the carb inlet - rather than the air cleaner.

Posted: Thu Jan 07, 2010 8:23 pm
by andrew.searston
its doesnt seem to be burning oil and it starts first time without problems. but it does misfire sometimes. the rocker breather is connected to the oil bath air filter. after a drive around you can see steam comeing out of the air intake.
bmc i cant see or find anywhere to connect the breather to the carb, has to be the air cleaner

Posted: Thu Jan 07, 2010 8:49 pm
by aupickup
then u need a different carb

Posted: Thu Jan 07, 2010 8:50 pm
by andrew.searston
ive just had it rebuilt, and its the original setup
heres a pic of what i mean (before its was rebuilt)
any suggestions???
or is it replace the rings<br>Image<br>

Posted: Thu Jan 07, 2010 8:58 pm
by eastona
surprised that it's like that if it's recently been rebuilt.

Is it really a plume? As others have said, some coming out is normal when they're disconnected/opened, a plume isn't.

If it isn't using oil, it's running OK and not churning out blue smoke, just drive it.

Andrew

Posted: Thu Jan 07, 2010 9:03 pm
by andrew.searston
cant quit work it out
just a worn engine i think
the carb has nothing to do with the breather and is ok

Posted: Thu Jan 07, 2010 9:46 pm
by eastona
I think BMC's point was that if it is connected to the manifold the draw on the breather would be better and therefore better ventilate the crankcase, therefore reducing oil loss

(a byproduct of blowby is that more oil than usual escapes past oil seals, better crankcase ventilation improves that).

Posted: Thu Jan 07, 2010 10:24 pm
by bmcecosse
If it's running ok - as others have said - just run it!