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Impeller replaced, but did I screw up?
A normal person with even a smidgen of mechanical aptitude wouldn't ask this question, but, well...that's not me.
I recently bought an '86 Hunter 28.5 and, after reading here about the importance of periodically changing the raw water pump impeller, I decided to ask the previous owner, who had owned the boat since new, when he had last replaced the impeller. What's an impeller? he asked. The impeller in the pump was the one that came with the boat from the factory in 1986! So I ordered the part from Yanmar and, after being assured by members here that it was an easy job, decided to install the sucker today. When I opened the pump up, I was shocked to see that only two of the six impeller vanes were still there, but they apparently had been moving enough water to prevent serious overheating. Using the Yanmar manual, I carefully removed the old impeller, put in the new one, got the vanes all headed in the right direction, cleaned off the old gasket material, applied some sealant to the new gasket, put the thing back together, opened the seacock, and cranked her up. Can't tell you how proud I was to see a cloud of pink in the water behind the boat (you can't see the cooling water discharge from topside on the 28.5, so the antifreeze being discharged told me the pump was at least moving water through the engine). Proud again when I checked the pump and found no leaks. To make this long story shorter, I apparently was so anxious about getting the old impeller out, the new one in, and the pump re-sealed that I overlooked one of the steps -- putting some grease on the impeller sides and blade tips. Didn't even think about it until several hours later and a hundred miles away from the boat. Is that a big oversight or a little oversight? Would someone please tell me it's a little one since I won't get back to the boat for a few days and the gasket sealant will be fully cured by then, which would necessitate my ordering a new gasket and going through the whole process again. Also, is there an easy way to determine if any of the missing four vanes are stuck in the discharge line? Should I shoot some compressed air in the line to make sure it's clear?
Sorry for length of the post, but I am truly half brain-dead when it comes to mechanical things and I tend to worry about things until they're resolved. Any help on this subject would be greatly appreciated. Thanks.