Thru valve rebuild?
- Thread starter lesrrt
- Start date
If your 27 has gate valves you should replace them with marine bronze ball valves from one of the big Suppliers rather than try to repair them.
It's possible to replace the valve while in the water by using a wooden or other plug into the they hull from the outside but it's very risky. There a good chance that in trying to remove the old valve the they hull will beak or dislodge and then you'd be stuck or maybe even sunk.
if you have a barrel or ball valve you may be able to service it while in the water but it a big risk
Hey thanks!
Boat is out. Probably going to just cap the end for now. The head is already removed as the water heater. Just tricky getting pipe wrenches to do anything in the limited space. With all the other work I have to do, I'll let this go till next season.
Boat is out. Probably going to just cap the end for now. The head is already removed as the water heater. Just tricky getting pipe wrenches to do anything in the limited space. With all the other work I have to do, I'll let this go till next season.
Just finished doing the job on my H27. Not the worse job i ever tackled, but right up there! I agree about the tight space for pipe wrenches. Ended up cutting the old gate valves apart with an angle grinder. Make sure you dry-fit everything first before you drill holes to hold the flange. Btw, if you've got a set of tap & dyes, you can use a large one for the thruhull tool. Saves a few $$. If ya end up cutting them out, you'll probably have to remove the thruhulls and repair the threads.
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I was hoping it would just unscrew apart and push through? It mounts on a glued piece on 3/4" square plywood block. Can this be done quietly or is a full assault with an angle cutter its destiny? Was planning on just capping. Didn't want to go that distance even tho. I am off tomorrow. Will report back with pics soon. Any senior techs on this board around Havre De Grace want to take a look? Cold beer and a cigar for some good advice ? Lol
An oscillating saw is great for tight spaces. All my gate valves on my H30 were frozen. I cut them all off, bought all new bronze thru hulls and flanged seacocks. Instead of plywood backing plates I used g10 fiberglass sheets bedded in glass reinforced resin.
Do this one RIGHT
As I've said many times before, I'd recommend Marelon seacocks for this. The problem described is what happens to inexpensive metal valves-- this problem does not happen to Marelon ones, ever.
Check my other posts for my reasoning on this.
The seacock in place is probably original to the boat. So it's been wanting to come out anyway. Check out Defender and others for the Marelon replacement. You can choose the head (hose end) angle from the Forespar website and then shop for that model number online. It goes in with just a little elbow grease and 5200 (use nothing else for it). You'll need to make/adapt a tool for a second person to hold the through-hull on the outside (I have one I made-- should get patented!).
If the inside of the hull is too concave at this location, make a backing plate out of fiberglass board, G-10 or even plywood (saturated in epoxy), and don't be afraid to make the backing plate much bigger in area than the base of the seacock or anything you may have removed from it. (My bet is that the old plywood backing plate will come off with a few light taps with the chisel. If so, it wasn't on with 5200.) You can get smallish blocks of fiberglass board from McMaster-Carr and others. The thickness isn't important-- only for the ability to shape it to contour to the hull. What's more important is the area, especially when using consumer-spec Marelon seacocks (I got OEM spec ones, which install differently).
When installing, DO NOT SPARE THE 5200. Usually I trowel up the excess and make a nice fairing about both the through-hull's mushroom head outside and the backing block inside. This is good for streamlining and for not providing places, inside or out, for gunk to find a home. Do not tighten till there's nothing left, but stop at about the first grunt. Make sure the lever on the inside is aligned how you want it and have the outside person turn the through-hull the last measure.
This is a vital job, one that will not brook doing it too casually. Take it seriously and get it right. As a pro I have done so many of these replacements that I could probably do it in my pajamas, half asleep, hung over, with one hand tied behind my back, on the phone, while a woman nags me about something. I am not far from you and I tend to work (for members of this site) for a beer and a steak sandwich (no onions). If you need any advice or help with it, you are ever welcome to get in touch.
As I've said many times before, I'd recommend Marelon seacocks for this. The problem described is what happens to inexpensive metal valves-- this problem does not happen to Marelon ones, ever.
Check my other posts for my reasoning on this.
The seacock in place is probably original to the boat. So it's been wanting to come out anyway. Check out Defender and others for the Marelon replacement. You can choose the head (hose end) angle from the Forespar website and then shop for that model number online. It goes in with just a little elbow grease and 5200 (use nothing else for it). You'll need to make/adapt a tool for a second person to hold the through-hull on the outside (I have one I made-- should get patented!).
If the inside of the hull is too concave at this location, make a backing plate out of fiberglass board, G-10 or even plywood (saturated in epoxy), and don't be afraid to make the backing plate much bigger in area than the base of the seacock or anything you may have removed from it. (My bet is that the old plywood backing plate will come off with a few light taps with the chisel. If so, it wasn't on with 5200.) You can get smallish blocks of fiberglass board from McMaster-Carr and others. The thickness isn't important-- only for the ability to shape it to contour to the hull. What's more important is the area, especially when using consumer-spec Marelon seacocks (I got OEM spec ones, which install differently).
When installing, DO NOT SPARE THE 5200. Usually I trowel up the excess and make a nice fairing about both the through-hull's mushroom head outside and the backing block inside. This is good for streamlining and for not providing places, inside or out, for gunk to find a home. Do not tighten till there's nothing left, but stop at about the first grunt. Make sure the lever on the inside is aligned how you want it and have the outside person turn the through-hull the last measure.
This is a vital job, one that will not brook doing it too casually. Take it seriously and get it right. As a pro I have done so many of these replacements that I could probably do it in my pajamas, half asleep, hung over, with one hand tied behind my back, on the phone, while a woman nags me about something. I am not far from you and I tend to work (for members of this site) for a beer and a steak sandwich (no onions). If you need any advice or help with it, you are ever welcome to get in touch.
What an offer!
Wow, I'd take him up in a heartbeat. Find out how he likes his steak, first, though.
Thanks for the vote of confidence, Stu! Now I'll owe YOU a beer.Wow, I'd take him up in a heartbeat. Find out how he likes his steak, first, though.
1) Do a scratch test on the old thru hull (scratch off a little of the bottom paint) and if you see any pink metal you have dezincification and you should replace the thru hull.
2) If the backing plates inside the boat and the thru hulls are in good condition and you don't want to try to cut the old valves off I've had good success with the following:
3) Liberally soak all the pipe threads with a penetrating fluid. I find the PB Blaster spray is much better than Liquid Wrench. Soak the threads a few times a week for a few weeks and tap each pipe at the threads with a small hammer each time you spray. This helps the fluid penetrate.
4) When you are ready get a plumbers propane torch. Have wet rags and a bucket of water nearby just in case. Heat the valve at the threads with the torch. It should get hot so a wet rag sizzles when you touch it to the pipe but not red hot.
5) Using assorted pipe wrenches (also called stilson wrenches) or a strap wrench you can usually get the valve off. You may have to remove the top of the valve or cut off the small brass stem with the handle on it if you need more space. I always wear work gloves while I'm trying to unscrew hot pipes to keep from getting burned.
6) If the thru hull starts to turn STOP. You'll need to get someone outside the boat to keep the thru hull from turning by putting the handle end of a small adjustable wrench or some other rectangular metal piece into the thru hull and then grab the end with a pipe wrench to keep the thru hull from turning while you go back in and try to unscrew the valve.
I've removed and replaced all the valves on my 1978 H-27 and 1983 H-30 in this manner. I really works and yes it's working in very small spaces so a small person (unfortunately all my kids are full grown and bigger than me and my wife just won't cooperate) or contortionist would always help.
Good Luck.
PS: If you have to remove the thru hull Maerlon are an excellent alternative to bonze.
2) If the backing plates inside the boat and the thru hulls are in good condition and you don't want to try to cut the old valves off I've had good success with the following:
3) Liberally soak all the pipe threads with a penetrating fluid. I find the PB Blaster spray is much better than Liquid Wrench. Soak the threads a few times a week for a few weeks and tap each pipe at the threads with a small hammer each time you spray. This helps the fluid penetrate.
4) When you are ready get a plumbers propane torch. Have wet rags and a bucket of water nearby just in case. Heat the valve at the threads with the torch. It should get hot so a wet rag sizzles when you touch it to the pipe but not red hot.
5) Using assorted pipe wrenches (also called stilson wrenches) or a strap wrench you can usually get the valve off. You may have to remove the top of the valve or cut off the small brass stem with the handle on it if you need more space. I always wear work gloves while I'm trying to unscrew hot pipes to keep from getting burned.
6) If the thru hull starts to turn STOP. You'll need to get someone outside the boat to keep the thru hull from turning by putting the handle end of a small adjustable wrench or some other rectangular metal piece into the thru hull and then grab the end with a pipe wrench to keep the thru hull from turning while you go back in and try to unscrew the valve.
I've removed and replaced all the valves on my 1978 H-27 and 1983 H-30 in this manner. I really works and yes it's working in very small spaces so a small person (unfortunately all my kids are full grown and bigger than me and my wife just won't cooperate) or contortionist would always help.
Good Luck.
PS: If you have to remove the thru hull Maerlon are an excellent alternative to bonze.
When I replaced mine I used a 41/2 grinder and carefully removed the mushroom on the outside. Then go to the inside and pull the remains out