Base pressure.

[2011195BR]

I got a Mercruiser 4.3 MPI and at 4,200 RPM plus I start getting water in the base and pushes out the dipstick tube. Below 4,000 RPM everything seems to be fine. I was wondering if anyone got any suggestions. I found a hose that comes from the thermostat housing and goes to the bottom of the exhaust manifold plugged with rust and flakes of rust as well. I cleaned that out and it is still the same. I hope that there is someone who can point me in the right direction.

 

[JB]

Re: Base pressure.

The right direction is to the Mercruiser forum. Your engine is not an outboard.

I will move this for you.

 

[Bondo]

Re: Base pressure.

I found a hose that comes from the thermostat housing and goes to the bottom of the exhaust manifold plugged with rust and flakes of rust as well. I cleaned that out and it is still the same

Ayuh,... Welcome Aboard,....


My guess is that, that rust, 'n crud also prevented proper winterization last fall too...
The water froze, 'n cracked the block...