Exhaust cooling issues?

[Spivy30]

Last night I was out on the lake on my boat a 1987 Sea Ray with a 3.0 mercruiser i/o which was running great until it kind of bogged and shut down. Of course I was in the middle of lake and it would not restart, finally after 15mins it restarted and was running fine for about 10 mins and then the rubber exhaust coupler on the manifold blew out and it would not run anymore. What happened? I feel like I over heated the motor or something but I was never over 200 degrees and I had good oil pressure. I checked the oil and it looks clean and perfectly normal. I pulled off the cooling hose that goes to the manifold while the engine was running and there was a slow stream of water coming out. Do I need a new water pump?

 

[Spivy30]

Re: Exhaust cooling issues?

I just checked the compression and it was all 120lbs. I'm putting a new water pump in to see if it cools better

 

[Haut Medoc]

Re: Exhaust cooling issues?

If you blew a hole in the rubber exhaust 'boot', I would say that either you burnt it from lack of exhaust water through a clogged riser....
OR, your exhaust shutter has broken off & is restricting flow either in the y pipe or stuck in the bell housing....
200 degrees is too hot, no matter what.....
I would check for raw water flow in by removing the inlet hose, running the engine...
If that appers good, pull the riser & drive to inspect exhaust issues...

 

[Spivy30]

Re: Exhaust cooling issues?

The parts guy said the raw water house should just shoot water apposed to mine that was just running out like a garden hose

 

[Bondo]

Re: Exhaust cooling issues?

Ayuh,... That motor's been run without water flow,.... ALOT.....

You'd better pick up a Complete New waterpump,+ impeller,...
Along with All the pieces mentioned by Haut,... I'm sure they're All Trashed by now...
You'll probably also wanta grab a Riser Gasket, so you can pull it,+ inspect it's ports...