- Joined
- Jul 18, 2011
- Messages
- 18,137
My new-2-me boat has the new style Mercruiser 'in-house built' engines and related goodies. The sea water pumps are supposedly good for 300 hours between impeller changes. My boat has 275 hours, so I decided to do them now rather than mid-season.
The old style pump used to be about a 4 hour process on my old boat. The new style are a bit easier, but being the first time doing them, it still took a while. The first step (as per the Merc manual) is to loosen the serpentine belt tensioner . . . of course, they don't tell you how to loosen the tensioner
. It turned out that just a long handle wrench on the tension wheel bolt does the trick.
4 bolts and the pump body comes out forward towards you.
The impeller is held in by the backplate, which needs to come off in order to swap out the impeller.
.
.
These pumps have the Mickey Mouse Ears gaskets and there is a gasket (o-ring) on either side of the backplate. I managed to salvage the other gaskets. Of course you can buy the backplate with both gaskets for a mere $50
. I decided that that was not going to happen . . .
Anyway, the pump bodies needed some paint, so I took care of that and went about removing the intake hose from the back housing of the pump that remains after you remove the pump body. My plan is to install a sea water strainer ahead of the sea water pump so as to trap any marine life that get sucked up through the outdrives. (FWIW - my outdrives have both the side and nose cone water inlets . . . so likely to pull in more marine growth in shallow waters.
4 hours later, I decided to cut the inlet hose as I could not get good enough access to pry them off. Anyway, the inlet hose on these engines are the 2-piece style with a coupler that joins them. The section of hose where the strainer will go is a mere 14", so it is going to be tight.
I could not get all the fittings needed for the strainers, so that will be tomorrow's task . . . find the fittings (1-1/2" NPT to 1-1/4" Barb) which seem to be a rarity.
Seeing as the sea water pumps had plenty of time to dry, I installed the impellers this evening and all went well.
.
.
The original impellers look to be in good shape, so those will go in the 'emergency spare' bin. Here are the pumps ready to go back onto the engines.
.
.
Hopefully, I can find the fittings tomorrow and get the sea water system all buttoned up.
The old style pump used to be about a 4 hour process on my old boat. The new style are a bit easier, but being the first time doing them, it still took a while. The first step (as per the Merc manual) is to loosen the serpentine belt tensioner . . . of course, they don't tell you how to loosen the tensioner
. It turned out that just a long handle wrench on the tension wheel bolt does the trick.4 bolts and the pump body comes out forward towards you.
The impeller is held in by the backplate, which needs to come off in order to swap out the impeller.
.
.
These pumps have the Mickey Mouse Ears gaskets and there is a gasket (o-ring) on either side of the backplate. I managed to salvage the other gaskets. Of course you can buy the backplate with both gaskets for a mere $50
. I decided that that was not going to happen . . .Anyway, the pump bodies needed some paint, so I took care of that and went about removing the intake hose from the back housing of the pump that remains after you remove the pump body. My plan is to install a sea water strainer ahead of the sea water pump so as to trap any marine life that get sucked up through the outdrives. (FWIW - my outdrives have both the side and nose cone water inlets . . . so likely to pull in more marine growth in shallow waters.
4 hours later, I decided to cut the inlet hose as I could not get good enough access to pry them off. Anyway, the inlet hose on these engines are the 2-piece style with a coupler that joins them. The section of hose where the strainer will go is a mere 14", so it is going to be tight.
I could not get all the fittings needed for the strainers, so that will be tomorrow's task . . . find the fittings (1-1/2" NPT to 1-1/4" Barb) which seem to be a rarity.
Seeing as the sea water pumps had plenty of time to dry, I installed the impellers this evening and all went well.
.
.
The original impellers look to be in good shape, so those will go in the 'emergency spare' bin. Here are the pumps ready to go back onto the engines.
.
.
Hopefully, I can find the fittings tomorrow and get the sea water system all buttoned up.
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