Need to replace H34 Engine Thru Hull Seacock

PGIJon

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Mar 3, 2012
856
Hunter 34 Punta Gorda
It appears that the sea cock for the engines raw water cooling is no longer closing completely and I'd like replace this ASAP. First of all the H34 is of the '86 vintage. While poking around, I noticed several folks seem to have the same valve. Secondly I have 2 questions...

1) I can't quite figure out the sea cocks model number or ID without removing it. Any help towards finding the correct seacocks would be appreciated.

2) I would like to replace ASAP this without having to haul the boat out... I just had it out a few months ago... I've read a few posts where someone had a diver cover the intake while making the change. Should the outside strainer be removed or is there some ingenious way of sealing the intake while the strainer is on.....

Thanks in advance!
 

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Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
like Stu said, that ball valve will just unscrew and you will get a nice stream of water till you screw in the new one. Should only take a few minutes once you get the old ball valve loose.
Be sure to not torque the thruhull as this could bust it and require an emergency haul out.
Isolate the thru hull by applying torque to the thruhull threads and the ball valve and not just twisting the ball valve against the boat.
With all that said it looks like the ball valve is in good shape. Could be it just needs to be worked for a while. you might want to pull the hose with the valve closed and add a bit of oil, place your thumb over the hole and working the valve.
 

PGIJon

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Mar 3, 2012
856
Hunter 34 Punta Gorda
Stand corrected and educated! Thank you Stu! Bill the problem seems as though the ball valve connection to the lever broke and is stuck in a semi-open position. Bill could you please elaborate on how to apply the torque to the thruhull while in the water. I apologies that I am still learning to maintaining this myself.... but I am learning!
 
Jul 1, 2014
252
Hunter 34 Seattle
I think what Bill was saying is you need to have a pipe wrench or something similar on the pipe connecting to the thru hull in addition to the wrench on the ball valve. When applying force on the ball valve side you need to apply opposite and equal force on the other side so the thru hull is not taking any of the torque as you break it loose.

The method of removing the valve while in the water works best when you're able to turn the valve off. You said yours is frozen in a partially open state. You will start taking on water when you remove the flexible line to the sea strainer. You could still do it if you have a cork to plug the end of the ball valve.
 
Dec 14, 2003
1,393
Hunter 34 Lake of Two Mountains, QC, Can
Stand corrected and educated! Thank you Stu! Bill the problem seems as though the ball valve connection to the lever broke and is stuck in a semi-open position. Bill could you please elaborate on how to apply the torque to the thruhull while in the water. I apologies that I am still learning to maintaining this myself.... but I am learning!
What Bill means is that you should take a tool (pipe wrench worked for me) and install it on the threads of the true-hull. Then install your other wrench on the ball valve and work it against the pipe wrench on the threads thus avoiding to move the true-hull and break the seal. you need to shut the ball valve first and remove the hose. It you succeed in breaking it loose, you will get a stream of water untill you screw the new ball valve on and shut it. You need to reverse the pipe wrench on the threads in order to tighten the new ball valve. If you have a diver available, with a large rag applied against the intake the stream of water will be much less. If your valve is leaking because it stays partially opened, then plug it up with cork or stuff a rag in it with your screwdriver. Good luck
 
Mar 20, 2012
3,983
Cal 34-III, MacGregor 25 Salem, Oregon
make sure you get a marine ball valve to replace the one in the photo... and the poly pipe nipple coming out of it is not a seaworthy fitting either.
either bronze or marelon... there are other choices also, but brass ball valves with carbon steel handles and poly pipe fittings shouldnt be there because you can have premature failures...
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
Like the other posters indicated you don't want to torque the thruhull-hull connection.Use a pipe wrench on the thruhull threads and a wrench on the ball valve.
If the handle broke off you can try vice grips on it. You do want to not torque the thruhull-hull in this case either so use a large set of channel locks on the ball valve.
As for the leak that will ensue when taking the valve out, since you have a hose on it you should be able to get the valve loose (1/16th turn) without taking the hose off. After the valve is loose take the hose off and then replace the valve as quickly as possible. While the amount of water coming in is alarming it is not going to sink the boat that rapidly is the bilge pump is working. Do have the area prepared to take a soaking though.
 
Mar 20, 2012
3,983
Cal 34-III, MacGregor 25 Salem, Oregon
and dont think you need to torque it down double tight when you install the new one.... if you have the proper sealant, go hand tight and then just a bit more with the wrench.... if you tighten it up like some think it needs to be, you will be hard pressed to get it loose after the sealant takes a set and it has been there a few years.
 

splax

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Nov 12, 2012
692
Hunter 34 Portsmouth
I would like to chime in here. I had my engine raw water through-hull changed recently. My motivation was that gate valves instead of ball valves were the through-hull closure. I had the boat hauled to do it and the other four. I went from 1/2" to 3/4" to give the engine raw water pump an easier job.

You should be able to replace that ball valve, but it is an awkward space in which to work. Avoid stressing the through hull at all. It looks as though there are flat flange edges where you may have a wrench to keep any pressure from being applied to the through- hull. If you loosen the hose clamps a bit you can turn the ball valve with out removing the hose.

I would shut the valve, remove the handle, loosen the hose clamps, wedge the wrench on the flange flats held with my foot, then apply force with an adjustable wrench to remove the valve countered by the wrench on the flange flats. Immediately after spinning off the old valve I would wrap Teflon tape on the through-hull threads, reverse the wrench on the flange flats, spin on the OPEN new valve, close the valve, and pop on the hose. This allows you to make sure everything is a fit and works while some water is leaking into the boat and you are able to take a breath and make sure you are set.
If something is not right you can spin off the new, spin on the old, and you are back where you were without damage.
 
Jan 22, 2008
1,654
Hunter 34 Alameda CA
If you put a pipe wrench on the threads of the current through hull they will get ruined and if you ever need to remove it, that is going to be a chore.

If, as Bill R. suggests, you can turn the valve to full open with vise grips, then how about adding a second valve in series with that one. Only the second one will work and you can put a wrench on the original one to keep the through hull from turning. You just need to transfer your hose connector and get a short nipple to join the two.

Just a thought.
 
May 24, 2004
7,129
CC 30 South Florida
If you are concerned about the engine overheating with the reduced water flow of a partially closed valve you can remove the hose and use a screw driver to turn the ball in the valve to the fully opened position. Understand you will not have the ability to close the valve, which you do not have now anyways so it is important that the hose and clamps are in good condition as they will be the last line of defense. Keep a wooden plug handy. If you think about it I could probably count with the fingers on one hand the times in a year that I close the raw water intake valve so to say that my intake valve is stuck open is the equivalent of a normal condition and nothing to panic about. You could probably wait for the time of your next haulout. I would be hesitant to try and replace the valve with the boat in the water. There is a good chance that the thru-hull will crack or get fouled up when you try to twist the valve off. As long as you do not have a leak now I would rather wait until it is convenient to haul-out rather than attempt to replace in the water. Having a working valve is convenient but the sense of security it may convey might be exaggerated. Give me a good hose and secure clamps inspected often and I 'll trade for a non-working valve or no valve for that matter. Do get it fixed but it does not have to be tomorrow.
 

PGIJon

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Mar 3, 2012
856
Hunter 34 Punta Gorda
Once again, I am overwhelmed by the everyone's knowledge and your willingness to share that information! I feel that I am now armed with the knowledge of how to remove it safely in the water, However, I am slightly concerned of my abilities to get it right the first time without sinking the ship. So unless one of you are planning to be in the Punta Gorda area this week, I am going to go with a combination of Allan and Benny's idea and to 1) use a screwdriver to fully open the valve and I'll order the replacement valve and put it inline with the old one until I haul it out next time when I will use the advice on how to remove it while I am high and dry.

Was that the original one on the '86 H34? Can anyone confirm that this is the 3/4" ID one? I am waiting to see if the Combraco folks can ID the ID...

Thanks!!!!
 
Jan 22, 2008
1,654
Hunter 34 Alameda CA
Was that the original one on the '86 H34? Can anyone confirm that this is the 3/4" ID one? I am waiting to see if the Combraco folks can ID the ID...

Thanks!!!!
Jon,

We are hauling tomorrow afternoon and my first project is to change that through-hull and valve. I believe it is 1/2", so yesterday I bought a 3/4" through hull, and new Marelon ball valve. This seems like a good combination as the ball valve has straight threads like the throughhull thus avoiding the tapered thread mismatch requireing a flanged adapter.

Part of my motivation was that it seems that the intake is always getting clogged or partially clogged when I'm within a year and a half of my usual 3 year haulout schedule. This is even with a 3 month diver cleaning regimine. I hope the extra margin will help (and a little bottom paint up in the hole).

With that being said, I will let you know what is installed on mine (stock setup).

Allan
 
May 24, 2004
7,129
CC 30 South Florida
I have broken shafts in ball type valves and I don't mean just the handle. In order to fully open the valve the hose must be disconnected and with the use of a screw driver inserted inside the valve to rotate the actual ball. Water will be pouring out of the valve during this procedure but it can be easily stopped by placing a finger over it until you can get the hose back on. Regarding adding a second valve it is a valid idea but be careful about removing the old barb as it may not twist off easily and the application of force may bring about the very consequence we are looking to avoid. Have seen old valves and thru-hulls just collapse under what would constitute very little effort. Give it a try but if you see it is not coming out easily just connect your hose and wait for the next haul out.
 

PGIJon

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Mar 3, 2012
856
Hunter 34 Punta Gorda
I've learned a few more things this morning... 1) I uploaded another picture and it revealed at least 2 things. I must completely redo the thru hulls, the plywood bedding is soaked through and through. Also I removed the hose and as was suggested the flow was not bad. in fact I could keep it at bay with just a bit of finger pressure. I shoved a long screwdriver down the valve and confirmed that the valve is stuck fully open... I'm thinking that this has probably been the case since I purchased the boat.

On a whim, I called my diver and as it turns out he was planning on cleaning the hull on Friday. He has a special insert that controls the torque from under the boat which we'll try to use, otherwise I found I was able to get a wrench onto the through hull bolts. As I am thinking about it, I will probably use the wrench in any case. He also has a large toilet plunger that he pushes up against the hull to prevent water from rushing into the boat during the process. So with his help, I now plan to put in a new valve on Friday.

If I am unable to undo the valve easily, I will go back to Allan's idea and just add it in series until the next haul out or if the stem won't come out easily as Benny pointed out, I'll probably refresh the hose connection by cutting an inch of host off the bottom and re-clamp.


Thanks Allan.. Will be looking forward to hear how it went. Thank you all again! This board is invaluable! Thanks guys!
 

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PGIJon

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Mar 3, 2012
856
Hunter 34 Punta Gorda
Allan.. Could you consider posting some pictures as you replace the through-hull and valve?
Thanks!
 
Jan 22, 2008
1,654
Hunter 34 Alameda CA
my diver...has a special insert that controls the torque from under the boat
Jon,

He probably has one of those step wrenches for thru hulls. You may just spin him around if it breaks free as its like tightening a bolt in outer space.

Good tip on the plywood. I think mine is soaked too so I just scrounged around the garage and found a piece as a replacement. We will epoxy coat it first so that won't happen again. I don't think any of them were treated. Mine is squeezed between the hull and interior liner, with just a small hole to get access to the nut. Yours appears to have more of the liner cut away. I'm taking my 4" hole saw along to open it up. That way I can also caulk around the perimeter of the pad.

Since this will never be removed again should I use 5200?

BTW, I looked at your second picture on the original post real close. It looks like in the casting it says 1/2 so there you go.

Allan
 

PGIJon

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Mar 3, 2012
856
Hunter 34 Punta Gorda
Allan.. Yes.. After speaking with their customer service I took a metal brush to the fitting and indeed found the 1/2" .

I think I will also add a 3 way diverter thus allowing the engine to act as an emergency bilge pump. I'll run a hose with a strainer from there to the bilge or maybe in the H34 case, under the bilge.

As far as the 5200 goes I don't believe I have enough knowledge to answer that one, although I will be looking with great interest to what MaineSail or anyone of our other resident experts have to say.

-Jon
 
Aug 16, 2009
1,000
Hunter 1986 H31 California Yacht Marina, Chula Vista, CA
Before you do anything, I would look carefully at Maine's discussion of the proper mounting of this particularly important seacock and thru-hull. Unfortunately it is one that has sink-your-boat potential. Certainly my Hunter does not satisfy Maine's specs and it does not appear that yours does either.