cooling problem

[99yam40]

I have found that replacing the plate and cup along with the impeller is always a good idea, just a few dollars more for the kit than just the impeller, it even comes with a new seal for the pipe to the motor.
The housing is needed sometimes if it is worn or warped, but I believe the water will come out of the shaft area as it is not sealed with anything.

Find, pull, and test the thermostat to make sure it is functioning properly. Look at a parts break down if you do not know where or what it looks like

[spiro tsala]

thanks,ill give that a go.