Mecury 150 XR2 BlackMax Overheating issue

[ValleyLakeBassman]

Hey everyone, I bought my first bass boat and it is a Fish and Ski Champion. It came with a 87 Mercury 150 XR2 Blackmax and is had an issue where it overheated. I replaced the poppet valve and it does not weep. It sloved the issue, however it will still heat up passed 3/4 and eventually the gauge beeps. Another thing is, the pressure gauge is constantly moving up and down. The water pump "pisses" good but Im on the verge of replacing it as well.

 

[Chris1956]

Rebuild the waterpump and install new thermostats.

The poppit valve opens under pressure, so if the pressure of the waterpump is at the threshold of poppit opening, the gauge could show up and down water pressure. A new waterpump should solve this.