06 RM250 coolant in cyl.

 
Lost 3rd gear and rebuilt the motor, it ran great for about 10 min. and then
started blowing anti-freeze out the exhaust. I changed cyl base and head
gaskets...still dumping coolant into the cylinder. Where/how is coolant
getting in? Any suggestions?
Rob

  > Lost 3rd gear and rebuilt the motor, it ran great for about 10 min. and
then

doing same thing over n over with same bad result
is defination of insanity you just did it twice so your ok ;-)

suggest look for a burr somewhere best case or heaven forbid
you got a crack somewhere important . gasgets ,do they require
sealing goo , rtv gasgaginch ,

 sorry im an air cool guy just suggesting

good luck

 
RM250 as in two stroke RM? Did they build two strokes in 2006? Okay,
in two stroke RM, there is a o-ring on the head... I´d change it. If
not, you might have put the base gasket a little "skewed", to install
it, smear grease on it, will help it stay put when you align the
cylinder with the base on the guides, it´s easy to get the gasket out
of place while trying to align everything. Once, I forgot to reinstall
the guides (cylindrical thingies made of brass/copper, I guess) and
the bike (a Honda 200cc, air cooled) leaked oil like crazy. Is there
coolant in the oil? It could be the water pump seal...

--- Tiago

  It could be the water pump seal...

That was my guess also.

 Bad/broken head gasket seal is most likely.

Or...
Cracked head or cylinder.

Or does you engine have cooling passages elsewhere connected to the
combustion chamber or exhaust?

Good Wrenching to you!

Jim



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                Jim
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