Ok decided to haul out to replace leaking engine raw water intake thru hull and ball valve . In my 1989 Catalina 30. Should I replace it with another marelon or go with bronze?
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Bronze or meralon ball valves and thru hulls?
- Thread starter ChrisCall
- Start date
i would replace it with what is already there. way cheaper on both initial cost and the retrofit.
UNLESS... You are rigging it as an extended offshore cruiser, and will be using it as such, then go with bronze always...
there have been issues with marelon, and there are those that need to replace the bronze valves also.. and there are a lot of older boats with marelon valves without problems, but its possible that after 30years, they could start having issues any day now... who knows?
if the marelon has worked in the application for this long without any real issues, why spend the big bucks on bronze?... BUT, i would agree that your current marelon valve should be scrutenized and cleaned, and replaced if necessary....
UNLESS... You are rigging it as an extended offshore cruiser, and will be using it as such, then go with bronze always...
there have been issues with marelon, and there are those that need to replace the bronze valves also.. and there are a lot of older boats with marelon valves without problems, but its possible that after 30years, they could start having issues any day now... who knows?
if the marelon has worked in the application for this long without any real issues, why spend the big bucks on bronze?... BUT, i would agree that your current marelon valve should be scrutenized and cleaned, and replaced if necessary....
Just took it apart it was actually the wooden backing plate rotted. Should wood be used as a backing plate or something like a starboard? Also what should be used as sealant when new one is installed?
I used wood (marine ply coated in resin) for backing on mine with 5200 for bedding. In theory the wood should never really get wet. I am not sure Starboard has the same ability to spread the load as plywood.
Interesting video.
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The neck of the thru hull should a snug fit in the hole. I dry fit everything snug then removed and bedded the interior and exterior with quite a bit of 5200, enough to squeeze outside the hull and out from under the wood backer.
Interesting video.
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The neck of the thru hull should a snug fit in the hole. I dry fit everything snug then removed and bedded the interior and exterior with quite a bit of 5200, enough to squeeze outside the hull and out from under the wood backer.
The marelon has lasted for years so I would stick with that. Probably a good time to replace. Don't forget to lube it routinely. I would stay from 5200 if you think you might want to remove it in the future. It is an adhesive more than a caulk. As for backing, many people are using G10 backing for sea cocks. Soaking plywood in epoxy will last a long time, if prepared properly.
To be fair with the videos there is a HUGE difference in strength between a Marelon OEM / 93 Series seacock and a Marelon ball valve & thru-hull fitting. What Catalina was installing the the late 80's is not an ABYC complaint seacock installation.
