Over heating

[mduran100]

Hello Everyone, I have a 1994 Four Winn’s 180 horizon with a v8 5.0 Omc Cobra stern drive. Currently having a over heating problem while that boat is idling the temps will start to rise up but as soon as I put in gear & get the rpms up a little temps goes back down. Looking for answers & just changed water impeller. Only having this problem while on water,will run boat on water house & temp will stay normal. Any suggestions

 

[alldodge]

My guess is the impeller pump housing has some grooves in it which is causes the pump to not be able to pump enough. When its on the hose, water is being pushed instead of the impeller sucking

Either that or there is not a good seal on the pump housing

 

[MRS]

Buy the whole kit the plate and the cage and cover if it heated up hot one time will melt the cover and the metal housing will slip. And not let the impeller do its job.

 

[mduran100]

I don’t think it has to do with the water impeller it was just changed with housing & did this previously before it was changed. What else do you guys think it could be? Could it be a bad thermostat like in a car? Do boats has thermostats like cars?

 

[MRS]

Yes they do.

 

[Scott Danforth]

if the seal between the drive and the gimbal is missing it will overheat at idle.