4BY2 Zinc size

[captstu]

Hi,

6 months ago, I replaced the 2 4BY2 engine zincs with the zinc assembly (nut, washer, and zinc). At that time, I also ordered a set of zinc replacements, p/n 120650-13420Z Yanmar Engine Zinc Anode (Zinc Only).

Boat zincs sold me the two parts. The assembly fit perfectly - I checked them at 6 months and wasn't surprised they needed refreshing.

I saved the bolt/cap part of the original assembly, cleaned it in Barnacle Buster to remove the trace zinc, and screwed in the 120650-13420Z Yanmar Engine Zinc Anode (Zinc Only) I had previously ordered. Yesterday I removed the old assembly and screwed in the replacement ones, original bolt, new washer (OEM), and new zinc studs. The innercooler went in fine - fully tight with only hand screwing and finish tightening to crush plus 1/4 turn.

The heat exchanger went in only with significant difficulty - and only after I filed the zinc to remove some material. Then it tightened with a wrench to what seemed tight.

Today the heat exchanger zinc fell out, finally tripping the water alarm so I stopped until the bilge pump caught up with the flood and i found the leak.

At that point, I took the zinc out of the assembly and screwed the bolt/cap back in to get home.

The OEM zinc assembly seems to fit, the replacement OEM zinc used in the original cap is to long to fit in the heat exchanger.

Is there another part I should order - or just grind 1/4 inch off the zinc before installing it?

Thanks

 

[Brian B]

After you replaced the heat exchanger zinc the assembly backed out after you had some difficulty tightening it? I wonder if there is a piece of an old zinc in there not allowing the new zinc to go all the way in. I have always used zincs from
boat zinc.com and have never had an issue. The top zinc lasts about 6 months, the bottom zinc about 3 months.

 

[captstu]

Brian,

I purchased the zincs BoatZincs just as you did.

The first zinc replacement I use the entire assembly, the zinc, the bold, and the washer.

The second time, I reused the boat.

The first time it worked fine and lasted about six months just as you said.

The second time I just screw the sink in to the bolt hole. This is when the problem occurred on the top Zinc.

I probed around was her driveway and saw the remaining piece.

I ordered a new set today from BoatZincs and walk carefully compare a full assembly with the replacement zinc.

I was curious if anyone else saw this problem?