8.1 Crusader Raw Water Pumps

[Uhehner]

I'm having problems with the Raw Water Pumps on my 8.1 Crusaders 2001.They last about 3 years at best and then start leaking and spraying water all over the engines. This can cause major damage if not caught in time. The water then causes corrosion on the mixed metal (brass, steel, aluminum ) high pressure fuel pump (I replaced them) that corrodes through and sprays gasoline creating an explosion hazzard. These are Sherwood P110 pumps, about $400 plus labor, stainless steel with a cheap rubber seal that allows water into the bearings and it just gets worse from there. There is no support for the impeller end of shaft and my guess is that's the problem. The Sherwood pumps on my old 454's were over 10 years old and still not leaking. They had support on both ends of the shaft. I am now retrofitting the engines with the newer (2005 and up) pumps. Any comments or experience would be appreciated. Capt. George

[31Tiara2001]

I have a 3100 with 8.1's also. Same year 2001. Both of my pumps were updated to the newer style, I think 2003 and up in the parts catalog. Both were leaking.

Jeff

[Chris Burkard]

I do not have specific information on 8.1 Cruisader Pumps, but here is a tip I learned years ago.

Raw water pumps have weep holes to let you know when the pump seals fail. Vessels that sit for long periods of time can develope minor corrosion on the shaft up against the seal inside this weep hole. When you fire up the engine the corrosion chews at the edge of the seal. The more damage to the seal, the further inward of the seal the corrosion develops. Eventually the seal begins to leak.

Tip: Pump the weep holes full of synthetic silicone grease. The synthetic grease won't damage the seal and it keeps corrosion from developing on the pump shaft.