Moving the engine seacocks

I have a 1986 Trojan 37 Sport Sedan. The engine seacocks are in a very strange place, aft of the enginesalmost right against the aft engine room bulkhead. You can't accessthe seacocks unless you lift the floor over each engine to get atthem. The genset sits between the engines so there is less than afoot between the aft end of the engines and the forward edges of thegenset. With the floors in place, if I stretch out my arm as far aspossible I'm still about one foot from the seacock lever. This makesno sense at all. So my plan is to move them along with the seastrainers to the front of the engines. Lots of room there to crawlin and around the far side of the engine even with the floor inplace. I'm wondering if anyone else has done this?


The only thing that I'm wondering aboutis that the inside hull area where the seacocks are now, appears tobe almost an inch thinner. An area of about 12in. x 12in. is sort ofstepped down right around the seacocks. I'm wondering if that'sbecause the hull is too thick to screw the thru hull fitting into theseacock threads on most bronze thru hulls of the day because theymight not have been long enough? That sounds like a stretch, but whyelse would the hull be thinner right there?


I'm planning on using Marelon for mythru hulls and seacocks. I believe the Marelon countersunk thru-hull1-1/2” 250 series is 3” long. The backing plate material isabout 1/2” thick so hopefully the thru-hull fitting should be longenough in the area of the hull forward of the engines where the hullappears to be about 1” thicker than where they are situated now. Does anyone know the bottom hull thickness of this boat? Is anyonefamiliar with the area around the seacock being about one inchthinner?
Thanks for any and all replies
Cheers

I started to replace a Marlon thru hull and seacock to replace my original bronze ones. I don't know if the thru hull was defective or I over tightened it but it snapped the head off so I said the heck with that and went back to bronze for the thru hull. On the other hand I used the Marlon seacock and it is great.

Usually buying long enough thru-hull fittings isn't a problem....not fluent I that particular hull but many builders were experimenting with cores in the mid 80's....they may have used it in your hull....that's the only rationale I come up with for the change in thickness, especially if they used foam.

makomark said:

Usually buying long enough thru-hull fittings isn't a problem....not fluent I that particular hull but many builders were experimenting with cores in the mid 80's....they may have used it in your hull....that's the only rationale I come up with for the change in thickness, especially if they used foam.

Click to expand...

Ok so using your rationale, are you suggesting that the reason it's thinner where the seacock is, might be because Trojan might suspect that the core material might break down over time and deteriorate because it has a hole through it, compromising the edge of the core, and then the seacock might leak? Or that Trojan would worry that someone might over tighten the thru-hull nut crushing the core material? So in that spot only where the seacocks are they went with solid fibreglass?
But then if that was the case why not build up that small one foot area with solid fibreglass to match the other thickness of the hull. The cost would have been negligible I would think, right?

Depends upon the engineer that made the decision and the constraints he/she had to work within.

I would hope the penetrations were made in the solid portion of the hull. If there is core in the hull, you don't want to any penetrations in the core without reinforcing the area (remove the core and put something solid in there).

Our Trojan does not have a cored hull. It is 1" thick in the engine room. I removed two thru-hull transducers and filled with west system and stranded cloth.
1995 Trojan 350 exp. Our boat was made by Carver