[capnward]

I am one of those who got milky oil in the crankcase from blown seals on the flange pump. I was afraid I needed a new head gasket, but the compression test was good. I thought maybe water was coming into the engine from the copper water jacket exhaust having corroded internally, but I was informed that would put water into the cylinders, a hydro-lock would result, and the engine would not run. I could see no water on the plugs, and the engine ran ok. I thought there was internal leaking in the block and/or manifold, but when I pressurized them with my lung power I heard no air escape, and the pressure remained while my eyes bulged out. I didn't believe it was possible for enough water to push past both the water and oil seals on the pump, and past the drain holes of the pump, to contaminate the crankcase oil. But somehow it did. The problem began after replacing a 2 year old impeller which looked ok, if a little bent. The engine ran hotter than before, and was not running well until warmed up, but it wasn't until I did the 50-hour oil change that I discovered milky oil. When I removed the pump, the oil seal looked like it was covered in vanilla milk shake. I had the pump rebuild kit from Moyer ready to go, and replaced seals, shaft, bearings, impeller, and O-ring. The shaft was badly scored at the failed seals, and the bearing at the water side of the pump was hard to turn. I had done the same repair four years ago, also after a new impeller had been installed. That time, water did not get into the crankcase, but the engine overheated when a lot of water came out the drain holes.The pump is 9 years old and has had two rebuilds. I do use the engine a lot. After 3 oil changes all is well.