Today I installed a Sherwood pump on our Onan MDKAV. This pump has a one-piece cast Bronze housing as opposed to the standard equipment which has a cast centre piece and two stainless endplates. I took out the Sherwood impeller and replaced it with a Global Run-Dry impeller (some people think the issue is that the raw water circuit is empty when the genset starts and that shortens the life of the impeller). These Global Run-Dry impellers can apparently run with no water up to 5 minutes without damage.
So we'll see if this solves the Onan impeller-eating problem !
Its pouring with rain here......yuk.....