I have Forespar Marelon valves as thru-hulls on my F35 Pedrick. The po had cable tied all the thru-hulls in the open position. I removed all the cable ties except for the 3/4" water intake to the electric head. For some unknown reason I left that cable tie intact. Of curse I would work that valve every time I was on the boat and me, myself, and I eventually cracked the valve housing. The cracked valve would leak pretty good in the open position and leak slowly in the closed position. I called a boatyard for an estimate - about $735 for haul, breaking out the old valve and replacement - 2 hours of work. Yard said they didnt do replacement parts.
I emailed Forespar with pics of valve - got their part number - they sent me instructions on replacement the valve in the water - so for $85 (part and shipping) I replaced the valve in the water - sweet. The handle have a white plug - plug fits into the hull-side of the thru-hull. Insert the plug with a string on it and work on the valve. Pull the string and done.
Pic at top shows new assembly. White plug is seen with loop. Bottom pic is cracked valve removed.
Im sure you all know that but it was sweet news to me!
I am starting down this same path. My engine seawater intake marelon ball valve does not totally stop water in the off position. I started to change my impeller, but with the valve in the closed position, considerable water was still coming through. Flow is slowed down in the off position, but still coming in. Postponed the impeller change till I get this ball valve sorted out.
I wrote to forespar to see if there was any kind of adjustment or repair, likely. Got a response saying it will need to be replaced, and to send pics.
Right. How old is your boat? Forespar wants us to routinely exercise those valves… I close my engine water intake and head intake every time I go out (weekly at least). The other marelon valves I exercise a couple of times a year (say 3-4x). Does your engine intake valve close all the way? An easy check of the condition of the valve would be to have a diver clean your bottom and while down there inspect the opening for debris or growth. If that’s not the problem, while he’s down there, have him plug the opening with he while plug (with a lanyard to pull out later). If that route, have your parts all ready with you…
I’d like to hear! Haha. I keep a jar of the marelon lube stuff but use it on my speed paddle housing when I take that out and other more accessible parts!
Forespar recommends using their marelon lube on the ball joint moving parts - ie take the hose off and smear the lube on the ball and work it - possible in the water but better on the hard but in either case a real pita
Hello Freedom lovers,
I realize this is an old thread, but we have the same problem on our 40/40 engine raw water intake as RichR did upthread - the valve (Marelon 87F1, apparently) leaks a bit even when closed. It is “exercised” frequently during the season, as every time we leave the boat we close it. Sometimes we even remember to open it before starting the engine.
I took the old seacock off, originally intending to replace it with a Groco bronze seacock. But upon removing the seacock I realized that the Marelon thru hull and the seacock function as a unit and I’d have pry off the marelon thru hull and the thick backing plate, and start from a hole in the hull. As the thru hull seems not to be leaking and looks clean, I’m not sure it’s worth the bother. Should I just replace the Marelon seacock with a new one? If so what is the correct size to buy (the seacock is 1" ID)? Or lubricate the seals and the ball on the old one and hope that fixes it? The boat is still on the hard and I’d like to get this resolved before it goes in the water. What do you old salts advise?
I’d say go with a new Marelon seacock. Groco makes great stuff, but it’s nice not having to worry about bonding/electrolysis for something so critical.
I wouldn’t try rebuilding the seacock. It may be totally fine, but it also may be totally beyond fixing, and you won’t know until you launch.
I have replaced a pair of Marelon thru-hulls after one failed on my boat, but I won’t necessarily say that you should replace yours. They were the thru-hulls for the large cockpit drain hoses, which discharge a couple inches above the waterline. A crack formed in one of them, and it was letting a very small amount of water into my cockpit locker. This immediately called my faith in Marelon into question. However, after realizing that said thru-hulls had the factory boot stripe paint on them, and were thus original to the boat, I felt better about it. For a plastic part that is partially exposed to the sun to last more than 25 years is pretty impressive. I was even more impressed when I tried to remove it, thinking it would only take a couple of hammer whacks from the inside to shatter the thing. After whaling on it for a few minutes, it didn’t even crack. I ended up having to use the oscillating multitool, which made short work of it.
So yeah, moral of the story: in Marelon we trust. Especially if it’s kept out of the sun.
Can you tell where the valve is leaking? Forespar is easy to work with - the valve has numbers on the side and you can call forespar and get a replacement kit - the handle lever, black stack with 4 bolts/screws. Pretty easy and inexpensive fix. Basically the replacement kit is everything in pic two above.
Hi,
Contact Forespar regarding your leak. They sent me replacement seals and handles. This was some years ago but worth an email.
Also, watch your thru-hull fittings just above the water line. The sun degrades them and they need to be replaced.
[quote=Camino post_id=55383 time=1682540261 user_id=6015]
Can you tell where the valve is leaking? Forespar is easy to work with - the valve has numbers on the side and you can call forespar and get a replacement kit - the handle lever, black stack with 4 bolts/screws. Pretty easy and inexpensive fix. Basically the replacement kit is everything in pic two above.
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Thanks all for your advice. The valve seemed to be leaking around the handle. Replacing the seals might help as you say.I ordered a replacement seacock off Ebay as a backup and will contact Forespar to get replacement parts.
We’d like to launch next week, but I guess replacing it in the water is OK if it still leaks?
Sorry haven’t seen this! With the boat in the water, take the white plug on the handle of the valve, tie a line to it, go under the boat and insert it into the through hole. Should fit perfectly Then with all parts ready at hand remove the 4 bolts, remove the housing, replace with nEw housing and replace bolts. When done pull the line to the cap and should be good. (“Should be…” is always an interesting word combination).
remove the 4 bolts, remove the housing, replace with nEw housing and replace bolts. When done pull the line to the cap and should be good. (“Should be…” is always an interesting word combination).