Offshoreonly.com - Gen 4 cooling

Quote:

Originally Posted by nordic95

Hey guys,

I just noticed looking at pictures of my old motors that I did remove the 1/2 bypass hose that goes from the top of the water pump to the old thermostat housing.My new housing does not have a provision for it.Can this be my problem?I think this would put water pressure from under the thermostat,is that right?That would act like a large hole in the thermostat to keep pressure even on both sides of it,I think.

Nordic95

I had the same problems when I put a supercharger on my Merc 425 HP Gen IV engine. The B&M manifold had also no provision.
Therefore I first plug the venting hose located on the top of the circulation pump and the cooling water temperature rose up to 100 degree Celsius (212 F).
After installing a pipe with a restrictor which I drained into the bilge the cooling water temperature became normal.

Joee