Yep I changed the anode and glad I did as it had disintegrated and a part was set to jam the water
flow. You need to be a contortionist and not claustrophobic! (have a friend nearby as I nearly got stuck!) I took out the battery
and spent hours head
first jammed into the space next to the generator. I started the work to get at the heat exchanger
as I suspected that the two failed impeller vane may have jammed there. See pictures, it was amazing that there was any cooling water
flow. I think I had the oil filter
off at the time to gain access.
Next I was able to get my arm around with a socket wrench through the small hole in the back panel and remove and replace the anode. See picture of old and new anode