I need some good sound advice. I have a polaris trial boss 350L 1992 2 cycle. It is leaking radiator fliud into to compression cylinder some how. I have already put a new head gasket on it. Some one told me that the problem could be water getting into the counter balance area. when I took the counterbalance out it did have water in it bad. Is it possible for water to get in the compression chamber this way. Any help would be greatly appreciated. Thanks

 

That is a problem with the 350's. The water pump bearing/seals are shot, fills the balance shaft sump - then the crank seals leak - allowing water into the crankcase, which is pumped into the cylinder.

Since you are getting water this bad, I would suggest replacing all your bearings/seals (crankshaft, balance shaft, water pump) - the damage is most likely already done, and a temporary fix will most likely leave you with a hole in the crankcase.