overheating

[TOP3]

My 350 Mercruiser shaft drive runs normaly with fresh water hooked up. But it doesnt seem to intake salt water to cool it . Any ideas?

 

[flashback]

Re: overheating

I would suspect that the raw water pump is worn out. the reason its cooling while on the hose is because the house pressure is forcing water thru the system. but when you put the boat in the water, the pump cannot pick up water on its own....

 

[MrBill]

Re: overheating

Yes, probably worn impeller in the lower gear case, especially since it cools on hose. How long since last replaced?

 

[TOP3]

Re: overheating

I replace it 1 1/2 years ago. That was my 1st guess . I am replacing it today. Thanks for your response.