Originally Posted by steve66
The impeller housing needs to be sealed with the lower part of the water pump. If its melted make sure it jahs a good mating surface with the lower part, also make sure the water pick up pipe fits well into the housing .If you have a leak at the pipe/ housing joint you will lose water pressure circulating the engine block . A bit concerning that the impeller housing has got hot, its usually been encased in water. Im wondering if maybe in the past a onr of the housing bolts have been a bit tight and some heat has been applied to help free??
Thanks for your advice.
The impeller housing seems nicely sealed when tightened with the gasket forming a nice seal. It's only the upper of the housing that has bubbling around two of the bolts, plus the tube to the pick up pipe. I did notice that the rubber housing joint is missing the two prongs that fit in the holes - it appears these have melted off, however I've ensured it's got a snug fit.
I agree, it's strange about the housing. The lower intake is complete free of obstruction so it should have always been encased in water. Very possible that someone has applied heat in the past to free a bolt, but they came out very easily for me...
I'll try it in water later and see what happens.
I didn't bother replacing the impeller because the one in there was perfect.