Water intake pump

[ddfenlon]

I have a 2005 Merc 350 Mag. My mechanic just replaced my water intake pump, the old one shaft froze. Now when I start water does not flow into it at first (idle) I have to run the rpm up to 2000 before water flows. Once it’s flowing it continues fine. Engine temp runs at 170 @ 2000 rpm and 180 @ 3000 rpm. i have had the boat 19 years and this is new since the pump change. Why doesn’t water flow start at idle?

 

[Bondo]

Ayuh,...... Welcome Aboard,...... Is it an Alpha, or Bravo drive,..??

 

[ddfenlon]

Ayuh,...... Welcome Aboard,...... Is it an Alpha, or Bravo drive,..??

It’s a Bravo

 

[Scott06]

I have a 2005 Merc 350 Mag. My mechanic just replaced my water intake pump, the old one shaft froze. Now when I start water does not flow into it at first (idle) I have to run the rpm up to 2000 before water flows. Once it’s flowing it continues fine. Engine temp runs at 170 @ 2000 rpm and 180 @ 3000 rpm. i have had the boat 19 years and this is new since the pump change. Why doesn’t water flow start at idle?

First thought is maybe the pump is sucking air on suction side and doesn’t flow til impeller is moving more. those temps are on the warm side especially the 180. Since you paid for the work I would discuss with the mechanic. Check hose clamps are ok and tight