Thanks Allan
Can you give advice on the parts I need and how the assemble comes apart. I'm pretty good mechanically but have not tackled this repair before
Tom,
Didn't mean to leave you hanging. We had a rather extended period of darkness out here, then I had to do some digging.
As you have mentioned then, it is your fresh water pump that is starting to fail. Mine did as well a number of years ago and once they get loose, rebuilding is usually not possible as housing wear can happen. Mine failed catastrophically at the absolute worst time as we were coming back from the Sacramento Delta and had just entered the SF bay with 25 knots of headwind and an ebb tide. The waves were 4 feet high and shaped like boxcars. I heard all this racket from the engine and the pulley was oscillating back and forth. There were ball bearings all over in the bilge. It took 7 hours to sail home instead of a 3 hour motor sail. Oh, and with the pounding the holding tank split from top to bottom. That took 3 months to deodorize.
I've attached a file from a Chilton's manual that describes the procedure for repair. Even they recommend complete replacement. You could try and rebuild yours as a spare, but amortized over the lifetime these things have, its pretty reasonable to just buy new. I have also attached the assembly drawing for the 3GMF motor pump. The pumps are the same for your 2GMF so you can refer to the part numbers there. I think you can find the replacement stuff at Kubota tractor supply outfits for a cost savings. You might consider pulling the thermostat as well (or at least buying a new one plus all the gaskets to keep in your spares kit).
Its not too bad of a job...4 bolts on the pulley, 3 bolts on the pump. You might have to burp it to get the air out of the pump. Just loosen something at the highest point and it should be fine.
Good luck.
Allan
