Hi all,
My husband & I are new owners of a 20 year old F45 which has been
lightly used, but not lovingly maintained. At this point of our
haulout, it’s time to replace the thru hulls - all 12 of them, plus
seacocks. Our question is this, which is the preferable material,
bronze or marelon? The issue with the bronze is not so much the cost,
but whether or not to go through the trouble to bond them again. If
there is no complete circuit, would there still be the risk of
electrolysis? What about lightning?
Any thoughts on this matter will be appreciated.
Thanks,
Julia (& Bill)
There was a recent discussion on this topic on the Columbia list.
The consensus was that bronze is better because Marelon does not give any
indication when it is ready to fail. It just falls apart with no warning.
Bronze that has deteriorated turns pink on the surface or when scratched.
But be sure you get real marine ones with SS ball valves. Some have brass
parts, which will undergo electrolysis quickly.
I think Hamilton Marine or Defender would sell you the correct seacocks/ball
valves. Even West Marine, which I do not recommend generally for reasons of my
own.
As for bonding, the jury is still out as to whether is solves the problem or
makes it worse. Even expert opinions vary widely. Is your boat has good zincs
and is not docked near any sources of stray underwater electrical current, it
should be fine without boinding.
Steve Gaber
Sanderling, 1967 C-31 #77
Oldsmar, FL
---- m0mzi11a <m0mzilla@…> wrote:
Hi all,
My husband & I are new owners of a 20 year old F45 which has been
lightly used, but not lovingly maintained. At this point of our
haulout, it’s time to replace the thru hulls - all 12 of them, plus
seacocks. Our question is this, which is the preferable material,
bronze or marelon? The issue with the bronze is not so much the cost,
but whether or not to go through the trouble to bond them again. If
there is no complete circuit, would there still be the risk of
electrolysis? What about lightning?
Any thoughts on this matter will be appreciated.
Thanks,
Julia (& Bill)
Underwater - Always Bronze
Above - Marelon except for Exhaust thru-hull, then I prefer Bronze to SSteel.
For Bronze products & Valves beware of far eastern imports, use a brand name such as Groco, Spartan, Apollo, Conbraco, Buck Algonquin, Wilcox Crittenden, Watts, Perko although some of these manufacturers bring in product from overseas, they normally ensure the correct grade of bronze is used and warrant their quality, beware there are non-branded bronze products out there that are not marine grade products.
Use a proper sea cock or ball valve made for marine use, not a gate valve and do not mix a brass thu-hull with a marelon ball valve, the theads are different and when using a ball valve there are specific thru-hulls that have the correct screw threads, that are different to those used with sea cocks i.e. Tapered, not Parallel threads. Mixing them will only give one or two threads of security and if knocked could break off easily.
Hi all,My husband & I are new owners of a 20 year old F45 which has been lightly used, but not lovingly maintained. At this point of our haulout, it’s time to replace the thru hulls - all 12 of them, plus seacocks. Our question is this, which is the preferable material, bronze or marelon? The issue with the bronze is not so much the cost, but whether or not to go through the trouble to bond them again. If there is no complete circuit, would there still be the risk of electrolysis? What about lightning?Any thoughts on this matter will be appreciated.Thanks,Julia (& Bill)