I have a 1995 4.3LX I bought new in 1995. Due to the 530 hours of my use, I decided to replace the impeller. Now that is it apart, I realize I am wasting my time. It looks like new (all fresh water use). I will replace it anyhow. I have one question in reading the service manual. What is the purpose of the "water pump face seal"? It slides down on the driveshaft above the metal water pump houssing (like the last step). The manual mentions a tool to position it properly?? What holds it in place? Is it an exhaust pressure deflector? If I read it correctly, it does not attach to the metal water pump housing. It just sits above it. The original water pump face seal looks like it might have been rubbing the top of the metal water pump housing a little bit. Thanks for the help if someone knows out there! firstname.lastname@example.orgMy web site on Homelite outboards
That little seal is there to keep the exhaust from aerating the water in the pump. I don't know what procedure you've read on installing that little guy, but the proper one is to push down on the drive shaft and slide the little plasic colar down the drive shaft to set the height of the seal (remove collar when done). I also put 2-4-c under the seal before I slide it down. Scott..
Thanks for the info on the coroded and pitted aluminum at the gasket surface. I have a very little bit. If it gets worse, how do you fix it. Sanding and painting it won't build it back up to original height. The service manaul says nothing about using gasket sealer on the bottom of the gasket. A Merc TSB (95-13)I found says to coat the surface with "perfect seal" make a gasket on the bottom of the gasket only. Since there is no part number of the "perfect seal" sealer, would GM make a gasket work? Thanks for all the help!