water circ pumps also need to be changed depending on water conditions one boats in for timeframe. Even running in the cleanest waters, I am lost why many boaters run around with a 15 to 25 year old water circ pump. Just throwing that out.

clear hose method will find your area for the cooling issues.

I finally got to the boat and looked around i noticed part of the thermostat gasket was torn and when i pulled the housing to replace the gasket i jotinot the water hose going from the circle pump to block has a decent kink type bend in it so I'm going to replace yhat and see what happens

Alright so I put everything back together and decided to double check all the hoses for debris. Apparently the "mechanic" I had change my impeller didn't backfluah the oul cooler at all, I had half an impeller fall out of the hose so I think it's safe to say I found the issue

Along with run a piece of stiff wire through all of the oil cooler tubes. I just spent over an hour this week dislodging little pebbles stuck in mine.

also, the merc pumps get scored on the end in the plastic housing and do not work well, most Merc kits include a new housing but many just change the impeller, which is fine some times..other not

Silly Rabbits. You have what we call in the business BRAVO ITIUS ! The water supply hose coming through the gimbal assembly is restricted due to the aluminum on the hose exterior corroding and decreasing the interior diameter of the hose. MerCruiser has an upgraded transom rebuild kit to alleviate the problem. The through hose is now a rigid plastic tube to prevent collapse. We do it all the time.

Ahhhh No, see post 13