Marelon seacocks

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Sea Gull

Member
Joined
Jun 14, 2012
Messages
16
Location
USA
Vessel Name
Sea Gull
Vessel Make
Californian 38 LRC
We need to replace some of the seacocks, and possibly thru-hulls, in our recently acquired Californian 38. Does anyone have experience with the Marelon products vs the traditional bonze?
 
Marelon seacocks sometimes get hard to turn. If you install them, make sure that you work them back and forth every few months. Other than that potential problem, they are trouble free.

David
 
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agreed...people that are afraid of "plastic" seacocks probably have no experience with them...
 
I've got two Marelon valves on my fore and aft toilet thru hull water intakes. They replaced the old bronze gate valves on my Californian. Like the other people said, they are good quality, but you have to work them every few months or they get darn near impossible to close or open. I have replaced my other gate valves with bronze stainless seacocks and they don't seem to have this problem. Big advantage is, you don't have to worry about electrolysis with Marelon. But if it's a valve not easy to or often accessed, then maybe bronze.

So choose your poison, easy to open or no electrolysis?? :banghead:

Larry B,
 
Plastic is great for Steel boats , BUT all plastic continues to harden as it ages.

We think nothing of relaping a 50 year old bronze real sea cock, for another few decades of service.

I'm not sure an aged chunk of plastic could take being jumped on in place after 5 decades,

bronze doesn't mind a bit, IF properly installed (Bronze 3/8 bolts).

How long do you want to keep the boat?
 
Thanks for the input, will keep it in mind as we inspect and make our decisions.
 
I've had a Maralon valve snap (not a seacock) and based on that experience I would be inclined to stick with the traditional bronze tapered seacocks.

For above the waterline use I would not be too concerned about using a Maralon valve. But for below the waterline I would stick with bronze for the reason FF describes-- a proven track record of decades of trouble free service with no attention other than routine servicing and adjustment.
 
When I replaced the 17 seacocks on our boat...all below the waterline.. I did consider Marelon units.....but...after really thinking about it..and considering the fact that the originals I took out of the boat were over 30 years old....
I decided to stick with bronze. I think that unless you are going to put in the recessed or "flush to the hull" through hulls....it is best to stick with bronze.

And in the long run....the price difference wasn't all that great...
 
I find it interesting that I too dismissed Marelon and installed Bronze. A bit ironic as they are installed in my plastic boat.

Caveat emptor; make sure you get real bronze. There is a lot of crap out there.
 
Seacocks are supposed to be able to withsatand a 500lb. lateral force.
When inspecting seacocks I put my foot on it and slowly apply pressure.

I learned the hard way :facepalm: not to do that with Marelon valves under 1 1/2" I.D.
 
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JAT said:
"When I replaced the 17 seacocks on our boat...all below the waterline.. "

Art DeFever did it right, we have one BWL through hull on our vessel.

This excludes 2 heads and the macerator.
 
Seacocks are supposed to be able to withsatand a 500lb. lateral force.
When inspecting seacocks I put my foot on it and slowly apply pressure.

I learned the hard way :facepalm: not to do that with Marelon valves under 1 1/2" I.D.

You didn't break a marelon seacock by stepping on it. Maybe the tailpiece or maybe the handle...maybe a marelon valve off a thruhull...but not a properly installed marelon seacock.
 
I have an old bronze seacock that's getting a bit hard to close. Does it just need maint or cleaning up or does it need replacement?
 
Service and maintenance. Good quality bronze seacock should outlast you and the boat.
 
What exactly does service and maintenance on a brass seacok entail? I have only ever slapped some grease on them and opened and closed them every couple of months, sometime they do need a tap from a hammer to get them moving.
 
Unless there is something wrong with them, regular, fairly frequent operation will be enough.

To service as below though the boat must be out of the water.

Sometimes though the taper plug must be lapped using lapping compound [car valves], Clover compound or grinding paste usually available from Industrial supplies and good car parts places. The surfaces can get rough and then sticky from the roughness.

Smear a light coating of compound on and insert the plug into the body and work it back and forth. This will smooth the mating surfaces. Wipe the stuff off, don't leave any grit and using some solvent to soak the rags, and if most of the surfaces are bright that should do it.

Grease and Reassemble and adjust the nut so there is a bit of drag and the thing should be good to go for a long time.

I installed a grease nipple in one side and would periodically shoot in a BIT of grease per side to help keep the operation free and smooth, valve in the open position so the grease is forced between the plug cone and body, not just into the cavity .
 
I installed a grease nipple in one side and would periodically shoot in a BIT of grease per side

The "best" grease fittings , that are OK in a bilge, come from the outboard dealers , not NAPA.

Both sides of the fitting could use some grease.

Folks that dont trust grease fittings can simply unscrew the 1/8 pipe winterizing plug , screw in the grease fitting , shoot and replug.

Doesn't take much longer , and is perhaps a bit safer.
 
When I replaced the 17 seacocks on our boat...all below the waterline..

That's a lot of holes in the boat!

I'm counting in my head right now!
 
I don't remember you being there :rolleyes:

Didn't have to be...have installed and used enough on commercial boats to know what they are really like...you can whack them with a 10 pound sledge and they are fine.... :thumb:
 
What exactly does service and maintenance on a brass seacok entail? .

This link has been posted before by me and others. For anyone interested in the full process of restoring a bronze seacock here is a pretty good photo essay on how to do it. [URL="http://www.pbase.com/mainecruising/boat_projects"]http://www.pbase.com/mainecruising/boat_projects [/URL]

Depending on the size of your screen the article you want is in the second or third row down, "Servicing tapered cone seacocks."
 
Greetings,
A number of years back I serviced all the seacocks on "my" vessel. As I recall, 18 both above and BWL. Most just needed a solvent cleaning and re-grease. The two main engine seacocks most probably had NEVER been out since installation since there was a stringer in the way that did not allow barrel removal. A 3" hole saw took care of that. I lapped those two with valve compound as described above, greased and re-installed. Now, I used wheel bearing grease and I found out afterwords that this was not recommended due to a component of the grease being incompatible with the bronze. All work just fine and I no longer need to use the "torque multiplier" piece of pipe the previous owner needed to cycle the engine seacocks.
As to Marelon...NO experience what-so-ever.
 
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