water/circulating pump elimination

[Limited-Time]

I know several boaters who have eliminated the circulating pumps on their 5.7 Mercruisers. They re-plumb the water lines and change the belts driving the alt. and power steering pump. The theory is the impeller supplies the water flow at low speed and the high speed requirements are met by the pressure generated by the outdrive moving through the water. I would like to hear the various opinions on this before I make any changes

 

[WillyBWright]

Re: water/circulating pump elimination

If it works, leave it in. That's a modification used on boats with motor-mounted water pumps and thru-hull exhaust that go very fast, not your average consumer boat. The Alpha drive pumps don't pump enough and an Alpha drive may not expell the water fast enough though the drive exhaust.

 

[f_inscreenname]

Re: water/circulating pump elimination

What WBW says.
I have everything mentioned above and when building my new motor this winter I thought about doing that but it was more headache then the 2 to 5 hp was worth.

 

[Bondo]

Re: water/circulating pump elimination

Ayuh,........

I have to Question,........

What would Circulate the water when the T-Stat is Closed,..??........

Seems to Me, that it would cause Hot Spots in the Block...............

 

[Limited-Time]

Re: water/circulating pump elimination

The reason for the question is during the pre-spring inspection I noticed signs of seal failure around the pump shaft. I guess I'll go order the replacement. Thanks for the input.