I have` an 88 250r that I just replaced the cases on. After reinstalling the motor and starting it I have a water leak around the pump. It is coming from what looks to be a hole under the pump(in the case and from the factory). If I am correct my manual is telling me that it is actually caused by the faulty three piece water pump that was used on all but the '89. Therefore if I replace with the '89 one piece unit, my leak should go away. Anyone else have this problem?

 

Yes, honda recommends that you replace impeller & nut on the 86-88 models waterpump. The 89 used an impeller that had nut as an intergral part of the impellor, not seperate as in the earlier years. However, the leak is probably caused by a faulty seal. It is wierd assembly, as it needs to seal the coolant in with the impeller, but it also needs to seal the case oil from leaking past the shaft. You could have either oil or coolant or both comming from that drain hole (I have had both). If your impeller is not damaged, I would just try replacing the seals. Your manual and your honda dealer should be able to help. Good Luck.

 

I replaced my water pump mechaincal seal over a year ago. My engine is an 86 and I replaced it with the 86 seal and have not had any problems yet. The replacement part is kind of expensive so be very careful when installing it. Believe me, I had to buy 2 because I put a small tear in the seal the first time.
ERIC

 

When you replace the seal also replace the oil seal at the same time being that you are in there. If you can have the dealer order one from K&L instead of from Honda, it is about half the cost and they both have the same stamping marks.