Greetings,
Mr. k. "never seen any evidence of electrolysis" Could it be that the wayward stub of the zinc is still in electrical contact with the body of the HE thus providing protection?
A problem I've run into the last couple of zinc service sessions is I've been unable to buy replacement zincs with the same threads as the existing brass plug. Likewise, my local zinc source does not have the replacements with the brass plug. "Nude" zincs only. My solution has been to re-tap the brass plugs. VERY easy. Same diameter, different TPI.
This zinc anode was in-service exactly 12 months. Look how it was chewed off at the base but the anode looks mostly intact. This is a Perkins 4.236. I would hope it would have wore down all over.
This zinc anode was in-service exactly 12 months. Look how it was chewed off at the base but the anode looks mostly intact. This is a Perkins 4.236. I would hope it would have wore down all over.
Very True. . .given the year of your boat I would assume you have Perkins 6.354-4 (Range 4) engines. If so, you probably have a manicooler instead of separate exhaust manifold and heat exchanger. You would have to confirm that though to be sure. I do not know if the manicooler had zinc pencils or not. Maybe someone else with Range 4's will respond.Interesting thread on zincs. My new to me boat (1990 marine trader) has 2 Perkins 6.354's and I was told there were not any engine zincs to change. Could this be correct?? If there are zincs, where would they be located??
Thanks!
Muriatic does dissolve the zinc and clean up the brass but unless you plan to run a die over the plug to recut the threads, which will further set the zinc into the cooler.. why bother
If you don't wait until there is nothing left you should be able to unscrew the zinc easily.
Just a little warning - putting zinc in acid produces hydrogen gas, lots of it. It's how we used to make "UFOs" when we were kids. Hold a dry cleaning bag over the reaction vessel and fill it with hydrogen, seal the bottom and let go. Extremely explosive! Be careful!