Overheat warning coming back to ilde on '84 V6 150 Evinrude

Changed my water pumps and took my boat to the river to knock the cobwebs off before going offshore next weekend. After running wide open for about 45 minutes and then 1/2-3/4 throttle for about 45 minutes, decide to call it a day. Slowed back to idle to move some stuff around and the overheat warning goes off, felt pee stream, it was hot. Shut it down and let it cool off. After it cooled down, started it up and felt the water coming out of the pee stream and the exhaust holes. Exhaust water overflow was hotter than the other engine, pee stream was cold. After all of this, the motor does not seem to want to take off when I give it the gas. Any ideas on the overheat/stall off idle? Any help would be appreciated.

Re: Overheat warning coming back to ilde on '84 V6 150 Evinrude

What do your spark plugs look like? Are any of them real clean looking?

Re: Overheat warning coming back to ilde on '84 V6 150 Evinrude

Hey DJ, checked the plugs and they all look about the same- light oil residue, good color, none really cleaned. So hopefully that means it isn't the head gasket. Could the thermostats be acting up? I also rememember that the engine seemed to be surging a little bit for the first 20 minutes at full throttle (I thought it was just maybe some trash in the carbs getting blown out). Any ideas now that maybe the head gasket is out? Thanks.

Re: Overheat warning coming back to ilde on '84 V6 150 Evinrude

I would do the t-stats on both motors. As for the head gasket - do a compression check before you start opening it up. If you have junk in the carbs knocking the cobwebs out probably won't do it.<br /><br />Do you have water pump pressure guages? If so what are the readings for both motors? That may tell you if you got the water pump installed correctly.

Re: Overheat warning coming back to ilde on '84 V6 150 Evinrude

No water pump pressure guages, but it ran fine for almost two hours until I came back to idle to turn around. I am planning on doing a compression test tomorrow to see what the readings are. I have read a couple of other posts where the impeller was sucking up some of the exhaust gases. Could an incorrectly installed exhaust housing affect this (the intermmediate piece between the lower and upper units)? It just frustrates me because it ran fine for over two hours. Thanks for the info. I will see about the compression test tomorrow. Anything else I can try without waking the neighbors?