1998 wr400f failures
Posted December 20, 2001 - 11:18 AM
Posted December 20, 2001 - 11:57 AM
THE CON RODS ON THE '98'S ARE KNOWN TO GO AT THE LITTLE END AND IF YOU DON'T CATCH IT EARLY, REV THE BIKE AND YOU COULD END UP FRAGGING YOUR ENGINE.
the sound of your little end going is that of a little knocking noise every time you rev the engine through mid revs. "the little man with the hammer"
this can be heard just as well while revving at standstill.
if you pull the top end down get the LE measured with an internal micrometer and check the spec on it.
if in doubt have it out.
Posted December 24, 2001 - 05:53 AM
Posted December 24, 2001 - 08:47 AM
My high mileage 98 WR needed cam chain and guides replaced at the 6000 mile mark. The motor was making noise at idle from the chain slapping the worn out guides.
The piston and rings were in tolerance but got changed anyway. I agree with Taffy's comments about the piston pin bearing. I have heard the same information from other reliable sources.
The water pump seal and impeller shaft are other must check items during a rebuild. I have seen several 98`s with coolant dripping out of the pump weep hole.
I have never heard of an oil pump failure on these machines or seen a posting on TT about one.
Posted December 24, 2001 - 11:29 AM
Posted December 25, 2001 - 08:45 AM
I have to admit ignorance. My 98 has never sprung a leak at the weep hole. I have never been inside the water pump.
The update on the impeller is a good idea. The part number for the impeller changed after 98. I can't say if your cooling will be better with it or not.
Posted November 21, 2006 - 10:23 PM