1996 evinrude 15 horse over heating

[Majakx]

My 96 eveinrude 15 horse will start up and run for about 20 minutes and it will just die and the motor will be really hot but then if i let it sit for about 30 minutes and it cools down it will start back up and run for a couple minutes then get hot and die again it has a brand new impeller that i put in saturday and it ran fine hooked to the water hose at the house but once i was runnin down the river it was starting to overheat really bad again...so does this mean i need a new thermosat???? Any info will help thanks

 

[bktheking]

Re: 1996 evinrude 15 horse over heating

Pull the stat out of the motor and check it in a pot of boiling water, a thermometer and something to suspend it in something like a colander. Check to see if it opens when it's supposed to or at all.