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Roy M · 27-11-2012, 16:01

Alternative suppliers of tapered cone seacocks are:

For the Europeans: Blakes Seacocks
For the Yanks: Bronze and Stainless Marine Hardware, Seacocks, Portholes, Thru Hulls - Spartan Marine Hardware and Accessories

Badsanta · 27-11-2012, 16:13

Check the threads. The thru hull has stright threads and your street ell is tapered. You might only get a turn or two. Thats the way I found them on my boat and am so glad I changed them. I would feel safer with the flange adaptor then the elbow.

Rhapsody-NS27 · 27-11-2012, 16:19

Quote:

Originally Posted by HopCar

Since you don't have room for a real seacock, think about using a Groco Flanged adapter with your thruhull and ballvalve. It solves the problem of mismatched threads that occurs when you screw a tapered thread ball valve onto a straight thread thruhull. It also gives you a flange that can be fastened to the hull.

Groco Flanged Adapter IBVF

I'm about to replace a thru-hull with one of these Groco types. The one I took off the boat was very loose because it was backed with wood and it got soft. I will do it better by trying to follow Maine Sail's site.

HopCar · 27-11-2012, 21:22

This is the setup I recommend to my customers for a low profile thru-hull assembly.

Blue Crab · 28-11-2012, 01:33

Quote:

Originally Posted by HopCar

This is the setup I recommend to my customers for a low profile thru-hull assembly.

Pardon ignorance:

1) are all thruhulls straight thread?
2) if so, I gather the elbow in your pic is st thread to thruhull, and tapered into ball valve?

3) Would there be a downside to replacing a 3/4" raw water intake with a 1" for a 13hp yanmar, or in fact a plus? That hose already has a T going to to either sink or head (not on boat at the moment to look).

4) 41 yr old boat with too MANY thruhulls: Head was replaced and moved and holding tank installed, new plumbing into new thruhulls. Old two capped off. All bronze. Couple of instrument accesses I don't care about. Sink and cockpit drains. With dessicating head, and drain relocation, I could remove all of 'em. I don't see a downside to WESTing them all in. Thoughts? Thanks

HopCar · 28-11-2012, 07:29

1) are all thruhulls straight thread?

Almost all are straight thread. I have seen some that are straight thread for most of the way but taper at the end to allow ball valves to be screwed on. I think it's a bad way to do it.

2) if so, I gather the elbow in your pic is st thread to thruhull, and tapered into ball valve?

In the picture there is a thru-hull fitting with male straight thread screwed into the bottom of a Groco Flanged Adapter (GFA)with female straight thread. The top of the GFA is male tapered thread. The Street Ell is screwed onto this. Both the street ell and ball valve are tapered thread. By using the GFA there are no mismatched threads.

3) Would there be a downside to replacing a 3/4" raw water intake with a 1" for a 13hp yanmar, or in fact a plus? That hose already has a T going to to either sink or head (not on boat at the moment to look).

I assume that the water pump">raw water pump is 3/4". In that case I don't see an advantage to going bigger on the intake hose. The sink and head that share the intake will draw only small amounts of water and shouldn't affect the engine cooling. That said, I would prefer the sink and head getting their water else where. Why not use one of your extra holes to provide water to the sink and head?

4) 41 yr old boat with too MANY thruhulls: Head was replaced and moved and holding tank installed, new plumbing into new thruhulls. Old two capped off. All bronze. Couple of instrument accesses I don't care about. Sink and cockpit drains. With dessicating head, and drain relocation, I could remove all of 'em. I don't see a downside to WESTing them all in. Thoughts? Thanks

You can't just slap some epoxy putty into the holes. There is a whole process that involves tapering out the holes and building up layers of glass. I'm sure the process is described in detail on other threads in this forum. The quick and dirty way to plug the holes is to be sure the thru-hull is cut off about an inch from the nut on the inside of the hull. Pack the thru-hull with epoxy putty and screw a pipe cap on it. If you do it this way, be sure the thru-hull is in good condition to begin with.

Blue Crab · 28-11-2012, 08:33

Thanks for info. My PO did some things well in my view, and others poorly. If there is a next boat in my future, I'll go for a previous owner like Delmarrey, or MaineSail, or the whole bunch of others who know what they're talking about mechanically.

"You can't just slap some epoxy putty into the holes. There is a whole process that involves tapering out the holes and building up layers of glass."

Yes sir. Tho I am a fan of QnDirty, I am less keen when it comes to the underwater parts. Some may not believe this but I brush my teeth in West 105, and rinse with acetone, beer, diesel, or whatever else is handy.

Cheechako · 28-11-2012, 08:49

"Look inside the ball-valve. Most of them step down in size at the ball. Only a few are "full flow"."
Yep, Plumbing boats is a frustrating task for those that look at the details
for sure. Many ball valves are very small inside the valve. It's too bad the marine industry never got together and created standards on things like this, would make life a lot easier. Straight threads, tapered threads, bad alloys arghh!

4) 41 yr old boat with too MANY thruhulls: Head was replaced and moved and holding tank installed, new plumbing into new thruhulls. Old two capped off. All bronze. Couple of instrument accesses I don't care about. Sink and cockpit drains. With dessicating head, and drain relocation, I could remove all of 'em. I don't see a downside to WESTing them all in. Thoughts? Thanks

I eliminated a bunch of thru hulls on one boat. It was a PITA, there were hoses running everywhere with Tees, clamps etc. I'm quite confident the boat was less safe after I was done. I think I probably had more $ in expensive hose and Bronze tees and fittings than the cost of new thru hulls.

Badsanta · 28-11-2012, 23:44

The photo has the flange adapter in it. The adapter has streight threads on the bottom for the thru hull and tapered on top for the valve or elbow. One other advantage is if you have a bad valve you can just replace it with out removing the adaptor or thru hull

Roy M · 29-11-2012, 08:38

An option for too many thruhulls and valves: Use one thruhull. Install a "seachest" manifold to it, using a single tapered cone valve (Spartan). The seachest can be a series of tees and nipples with a single cap at the top for "rodding out" the valve and thruhull in case of a blockage. The tees provide the supply to the engine, head, sink, watermaker, washdown, etc. Very old solution, low-tech, and deliciously efficient.

PamlicoTraveler · 30-11-2012, 05:22

Quote:

Originally Posted by HopCar

This is the setup I recommend to my customers for a low profile thru-hull assembly.

Hop....what kind of setup is that? Who makes it etc.?

S/V Alchemy · 30-11-2012, 07:09

Quote:

Originally Posted by Roy M

An option for too many thruhulls and valves: Use one thruhull. Install a "seachest" manifold to it, using a single tapered cone valve (Spartan). The seachest can be a series of tees and nipples with a single cap at the top for "rodding out" the valve and thruhull in case of a blockage. The tees provide the supply to the engine, head, sink, watermaker, washdown, etc. Very old solution, low-tech, and deliciously efficient.

This is what I have on my steel boat, but it's a "standpipe". It's a three-inch ID pipe that goes above the waterline with a gasketed cap. There are four 3/4 inch tee-offs, and it is those which are seacocked.

The only other "below the WL" holes in the boat are a galley drain outlet and a head drain outlet.

My only anticipated improvement to this is installing a hinged, sprung filter flap over the bottom of the standpipe. Apparently, a fairly substantial fish got in one time and had to be reamed out with a length of dowelling, poor little bugger.

HopCar · 30-11-2012, 07:29

Pamilco, That's just stuff I grabbed off the shelf in my store.
Groco Thru-hull
Groco Flanged Adapter
Street Elbow
Groco or Apollo Ball Valve

casual · 30-11-2012, 14:51

Quote:

Originally Posted by HopCar

This is the setup I recommend to my customers for a low profile thru-hull assembly.

Is that a groco fland adaptor modified for the thru to attach to the 90 elbow?I,have a 1" flange adaptor that I,have been working on all day.First I,cut it down 5 treads still to high,Because of the taper can only get 2 treads to screw on.My next step is to see if a machenist can retread the remaining treads smaller in diameter to allow the 90 to screw down to the base.Your adaption is one I,had rolling around in my head if in fact that is what you did.Please for the love of my knuckles tell me it can be done.

Thank's so much for the post.Dave