Engine water inlet seacocks

guydickinson

guydickinson

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Can anyone advise a source for these please? I know the engine manufacturer probably supplies them but this is a slightly odd one! I have a hole where the present seacock is but its a b**g** to get at and I wonder if one could fit a system whereby the piping does a right angle bend after coming through the hull, comes aft a bit to where I can reach it easier and have the actual lever there - or is that pretty unlikely?! I hate making more holes in a hull than necessary - as everyone I expect.
 
Whatever you do I would still have a seacock on the hull, and open/close it from time to time to keep it working.

The engine seacocks themselves are usually identical to other thru hull fittings, try ASAP or Vetus.
 
It can be done with a selection of fittings elbows,sockets,nipples ect but points to think about are the farther the seacock is away from the skin fitting the more pipe work is at risk as it cannot be turned off.
If you go this way I would use rigid pipe fittings up to the seacock but make sure the seacock is well supported and clipped so as to prevent any movement of this pipe when operating the seacock and loosening any joints.
pete
 
Following my experience, I would avoid having a rigid bend in the cooling water inlet. On my boat, the arrangement (I think fitted by Westerly in 1986) is: skinfitting, 90 degree elbow, ball valve, hose tail, hose, filter etc.
This winter, it's coming out because twice in 3 seasons the elbow has blocked with marine life. It causes a subtle, barely noticeable decrease in flow of cooling water over weeks.
I plan to arrange a straight line run that can be rodded to clear obstructions without leaving a hole below the waterline. However, I suspect that the bend provided enough shelter for the critters to feel comfy and if that is removed, I hope not to need to resort to mechanical devices in future.
Derek
 
I would agree that an elbow is not a good idea. When I re-engined, I would have needed the same to use the existing seacock, so I filled the hole and fitted a new cock with a vertical pipe. It is actually in a less convenient position for turning on and off, but is directly below the water filter.
 
I wish I was close to the boat to take a photo.
I replaced my seawater inlet which was a gate valve, with a marine grade ball valve which is so much easier to operate. The ball valve fits on to the skin fitting (threaded) with only the aid of PTFE tape. On to the ball valve is an elbow (25 years old I’m guessing, as old as the boat) which shows no sign of wear or deterioration (must be made of the right stuff). This has a plate on the top held with two butterfly bolts covering an internal mesh filter. I always shut the inlet when I secure the engine, and obviously open the same as part of the start-up process. No beasties or blockages in the elbow and always a good flow of water with no heating issues.
Hope this helps.
OGITD’s
 
Yes, that style used to be quite common, but has largely been replaced by straight through ball valve and remote filters. These have the advantage of being easier to access and clean and if sited like mine directly over the seacock allows one to clear weed etc without turning the seacock off.
 
[ QUOTE ]
... I wonder if one could fit a system whereby the piping does a right angle bend after coming through the hull, comes aft a bit to where I can reach it easier and have the actual lever there - or is that pretty unlikely?!

[/ QUOTE ]

VERY bad practice; don't do it! The first thing that ought to go onto a skin fitting is the seacock. The only thing that should go onto the seacock is a PTH (pipe-to-hose, or at most, an elbow and a PTH). Avoid, at all costs, a 'fittings tree'.

I would not even consider a remote operating arrangement because you need to be able to plug the hole in the hull if the fitting breaks.

I would definitely re-site the skin fitting to a more suitable location and sealing the old hole, not a big deal.

If you are interested, the subject of skin fittings is covered in considerable depth in the current issue of 'Professional Boatbuilder' (pages 82 through 92).
 
I'm sure that is very sound advice but....How do you plug a hole through the bottom of a GRP hull? With a fitting or fibreglass it? The latter seems a bit dodgy(?!)
 
Yes, that's the one. (Best trade magazine that I have found)

Re plugging the hole. Best way to do it is fibreglass. It is only a small hole and it is not rocket science. Basically it involves (1) remove old fitting (2) Grind around the hole, inside and out, to some 6 x the diameter. (Even a 'throw-away' small angle grinder will do - dirt cheap.) You need to expose the fibres, (4) clean area with acetone (5) Tape a stiff sheet of thin plastic laminate (waxed) over the hole from the outside (6) Mix resin with hardener and apply discs of fibre mat over the hole on the inside, increasing the diameter of each successive one, e.g. 3", 5", 7".

When these layers have cured, remove the plastic laminate and repeat the process on the outside. When fully cured, say two days, grind / sand smooth, fill any imperfections and give one more thin coat of resin / hardener. Job done!

For a better explanation, your best bet is Oldsaltoz, who has given detailed instructions on fibreglass quite frequently on these fora. You might want to look up his past postings, if that is still possible.
 
Did just this to re-locate the log transducer (new taller one wouldn't fit under the floor) and is easy enough if you have done any fiber glassing before. Crucial thing is to get rid of air pockets. Use epoxy resin, stronger, adheres better and IMHO is easier to work with... oh and seal off the area inside before you grind, it makes a heluva mess!
 
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