Perkins 4.108M Zinc Anode

[FinSailor]

Anyone knows if this exist on motor and where? The enigine is fresh water cooled.

[shakey doug]

It depends which company did the conversion most do not run anodes check all plugs within the raw water circuit.

[slacker]

Our Perkins 4-108 has the heat exchanger mounted at the flywheel end of the motor. There is a zink on the left side of the heat exchanger facing down. It is conveniently placed so that when you remove the old zink the salt water in the exchanger runs all over the engine mount.

There is another model of 4-108 that has a Bowman heat exchanger which is mounted under the header tank. I'm not sure where the zink is located on that one.

Good luck

[FinSailor]

Thank you both. I opened one over the exchager and it was empty plug One is facing down, but it is on right side. I will most propably try open all plugs that might have the anode.

[Dynamo1181]

The newer design 50hp 4-108 with the Bowman heat exchanger, does not use a zinc anode.
A

[osirissail]

If you pull the plug and don't see a pencil zinc - it doesn't necessary mean that one was not there before. It is probably dissolved away. Check the plug carefully with a knife or awl and scrap to see if there is a residue of the old zinc. Some pencil zincs have threads on one end so you can screw it into the heat exchanger plug. Of course, you have to remove the "stub" of the old zinc first.

[mdharnois]

That was my situation--the anode was completely dissolved. The retainer is a standard part but you'll need to cut a standard anode down by about half its length.

In terms of locating the anode, the shop manual is your friend and is available for download from various sources.

[FinSailor]

Thank you all for your help. I have not have time to check this yet (as the boat has several other issues), but coming a head on my task list.