Yanmar 6by2260 engine zinc discussion

[Nutedog]

Just attempted my first engine zinc change at 250 hour mark. Seaweed sits on lift in Southwest Flordia when not in use.

Process sounded easy and in fact it was until I discovered that the zinc itself had separated from the brass nut and appears and feels like it is still inside the housing. Of course it is difficult at best to get a good shot at seeing/feeling or removing the left behind zinc.

To complicated matters both upper and lower exhibit the same condition.
NOW WHAT ? Any help / insight here would be greatly appreciated.

The replacement is a one piece nut and zinc assembly (quite pricey I might add).

I have done a bit of research and see that there may be a two piece assembly (appears to be more cost effective) and a better set up any information on this would be appreciated.

Thanks

 

[Crewdog]

Many folks have used BoatZincs.com to order various zincs for engine, thrusters and props.

Here's a link to the brass plug/zinc for the 6BY260, which is also what is used in the 4BY180:

http://www.boatzincs.com/yan120650-13420.html

only $12.73 + shipping, and I keep a couple of spares.

 

[knotflying]

If you can install the new zinc assembly I wouldn't worry about it. The lost zinc will eventually disintegrate. And as Bill suggested Boat Zincs is a great place to get Zincs. They also sell one that has a screw in zinc cartridge, so you just have to buy the zinc and not the whole assembly.

 

[nzfisher]

I can't speak to the 6 cylinder but the zincs for the 4 cylinder are three pieces- a threaded zinc column, a copper/ brass washer and a bolt head that has threads that the zinc column threads into. If the 6 cylinder is the same, the remaining threads of the zinc insert that are in the bolt head can be removed with a little patience. The threaded zincs are available as a separate part that is then threaded into your brass bolt head. If you look at he Zincs.com website closely, you will find a section where they can be ordered without the bolt head at about 4- $6 each. Do not lose the copper washer. It needs to be reinstalled with the assembly. If you are a fanatic you can anneal the copper washer for the best possible seal. Oh, incidentally I find that I have to replace these twice a season or they are completely eaten away, which is probably what happened in your case.

 

[dante3756]

One caution - if the broken off zinc is restricting your insertion of a new zinc, do not force in a new one as you may damage an internal engine part.

 

[elan]

Good morning Nutedog,
To answere your question specifically, I have had the same experience once on my 4cylender Yanmar.
After a couple of try's I was able with needle nose plyers to retrieve the zinc.
When instaling the new zinc I hand tightened the new one into the brass plug as tight as I could.
Good luck!
Mike
M/V Elan
Cutwater 26\Yanmar 180 HP
2012

 

[Nutedog]

Thanks for all the input.

I managed to get old zincs removed after making a couple of speciality tools ( mini screwdriver with 12 inch long handle) which made old zinc removal possible. The top zinc was a it more difficult since more remained in the hole but after poking around and using tool to penetrate I fashioned a small hook on the end of a coat hanger and got in behind what zinc remained and pulled it out. Bingo. The bottom zinc was mostly a calcium build and easily removed with my new little tool.

I wil also check out the two piece assembly looks to be a significant cost advantage.

Moral of the story is on job so easy check more frequently.

 

[knotflying]

Besides checking more frequently, if you are using the screw in insert, put a little anti seize on the insert threads.I have had the remaining zinc snap off of the threads. An easy job gone bad! I had to then drill out and clean the threads of the bronze fitting.