450: L450 Genset Pencil Anode

[Emerald Sea]

Has anyone managed to replace their pencil anode on a 450 generator. It seems to entail the painful task of taking apart the STBD head cabinet work to access the backside of the generator. If someone has done this work I'd appreciate a few tips.

[DavefromNZ]

Hi Steve,

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

Enjoy :-)
Dave

[DavefromNZ]

Hi Steve,

I found this Onan Outline Drawing showing the aft panel (the right side as you look into the Gen locker) and if you look carefully at the bottom right of the image you can see the Zinc Anode access port.

Cheers, Dave

[PaulinOz]

Just had mine replaced the Service guy removed the Top, Starboard, Port and aft sound panels. He then lay with his feet on the tramp and body on the top of gen and reached down the starboard side of gen to the aft starboard corner with an 18 mm spanner to loosen then remove it. Not very much left of original anode and it is the original anode has white paint on the head. (which is funny when on the last service, I was charged for a replacement anode!!!!!!!) Hope this is of some help.

It appears to be tricky to get to but is very doable without cutting holes.

[Emerald Sea]

Thanks all for the above. Bit late in this reply as we've been offshore for most of the time and missed it. We arrive in S Africa next month and have lined up a service with Onan-Cummins which includes this pencil anode job. I normally do all my own maintenance but there is no way I can contort myself around this; just the filter change results in bruises and cuts! We have the larger 11kVa model.