where did the coolant go ??????

99 yz400 here are the sympthoms

high idle, it does not get affected by idle screw

could get it turned on like a two stroke without much effort

smells like its burning oil

after running for a while it started to puff out white smoke out of engine vent hose and afterwards it started to leak a little oil thru the same hose

other than that the bike runs fine but it smells like s**t, high idle but it doesnt semm to have a power loss (not that i would be able to tell the difference i bought it used about three weeks ago and never ridden a 400 before only 250) its just pretty fast.

so is it time to replace piston and rings or it couls be something else

after tearing it down here is what i found

piston is good

oil ring is not

oil is not milky however the is no coolant, where did it go?????

so it overheated and fried the ring but where did the coolant go

you just awnsered your oun question...it over heated and blew it....same happened to my 230 a while back, come to find out it was bad gas and sand in the carb, might wanna check!!

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