engine rebuild.

1 reply to this topic
  • yz426400

Posted March 29, 2015 - 06:09 PM


So I got water in my oil. I have what I hope is a 98-99 yz400f motor in a yz250f frame (guy told me it was a 426 at the time). It was run MAYBE an hour with the oil mixed. Here's my question, should I replace all the bearings in the case? I have a couple of buddies that are telling me to replace them all. I already have to do a new piston, water pump kit, valves, and a gasket kit. Just wondering how much more I'll have to dump into this bike or if I'm better off just parting it out and buying another used bike.




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  • grayracer513

Posted March 30, 2015 - 06:10 AM


The bearings don't need replacement because water got into the oil, but on that old a bike, they might anyway.  

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