Zincs are immovable and confirm location, please

[Blain]

I know there are 2 zincs on the heat exchanger, the manual says there are zincs at the raw water pump.. I just cannot locate that zinc. Also, are there other zincs on the V71. I am used to zincs at the tranny cooler but I cannot find such a zincs.

Someone painted the Zincs at the HE with a good amout of paint, they have a square head. I got a 12point 3/4" wrench on it but it is immovable. Attached a PVC pipe to the wrench.. still not moving. I did not push it too much. A 6 sided 3/4" sockets won't fit, need a 12point and a.breaker bar probably. First I am concerned that the zincs have not been changed in years and second, how hard can I pry these zincs head. I don't think that t hey will crack easily but not sure.

The 2 previous owners carried out fresh water flushes regularly. I wonder if they did not think zincs are needed. I ordered a good number of zincs, as I am keen to get things going fresh right off the bat.

I would love to hear your thoughts.

Thank you

Blain

 

[Captain Ralph]

The funny thing about Detroit zincs, In 30 minutes, the green water usually drains off from around them.

 

[rustybucket]

Use a box end wrench or good adjustable wrench for the square heads, not a 12pt, that is a recipe for disaster. If they haven't been off in a while some torch heat may be needed, heat them up, steady pressure on the plug, keep heating they should eventually turn loose. Just don't set the boat on fire!

 

[Briankinley2004]

Use a box end wrench or good adjustable wrench for the square heads, not a 12pt, that is a recipe for disaster. If they haven't been off in a while some torch heat may be needed, heat them up, steady pressure on the plug, keep heating they should eventually turn loose. Just don't set the boat on fire!

Heat works wonders if someone put pipe dope on them. Doesn't take much to soften it and allow them to turn.

 

[Streff]

I had the same issue. I used a heat gun & channel lock with a long handle, I was able to get out the inlet side Zinc at the HE (it was 20% consumed), replaced it with a new Zinc, but could not move the one on the outlet side. I will come with more heat.

the key is to have good leverage and heat and it will come.

 

[Captain Ralph]

To reduce flame ups (burning paint), use stripper and remove all the paint from around the plug.
There are square head sockets available if you prefer the correct tools.

 

[dsharp]

Get an 8-point socket and a break over bar or an impact if you have room

 

[Blain]

Thanks to all of you, I was finally able.to remove most of the old zincs. I needed heat, my longest breaker bar and even pain remover. Due to access, I used my biggest Cresent wrench on some.

Half the removed zincs were minimally consumed, the other half were 30% consumed at most. Interesting, since the boat cruised over 2 years and over 2000 miles on these zincs.

I will probably use heat to remove the bolts leading to the Transmission screen when changing its oil. They are also painted over.

Streff