Best Way to Install Sea Cock

[smurphny]

Took old, frozen tapered engine intake sea cock out yesterday to check it for corrosion/electrolysis. After cleaning up, it looks fine but was surprised to see that the only thing holding this in is the 3/4" bronze thru-hull tightening up into the seacock. The seacock itself is not bolted to anything. This seems to me to be less than adequate. If the thru hull part were to crack or get sheared off, the whole damned thing would just fall off, leaving a 3/4" hole below the waterline. The seacock unit itself has the usual bolt holes but it's obvious there were never any bolts. Is this s.o.p.? Wouldn't it make more sense to sturdily glass a plate on the inside with a couple of carriage bolts coming up through it to hold the seacock securely in place?

[capngeo]

Best Way to Install Sea Cock

On the hard! LOL

Many through hulls are held only by the threads. The additional flange is a dandy thing in wood or if there is a dynamic load on the seacock (such as a strainer)

[Hodidoo]

That nut and a liberal application of 5200 sealant will be more than enough

[smurphny]

On the hard! LOL

Not only on the hard, just able to get through snow banks to get to her! Grrrrrrrrrrrrrrrr. Was headed south last November, off Delaware when a number of problems added up to the decision to head back up home to Lake Champlain and make a few more repairs before setting out again. I'm not LOL after this crappy, cold winter. Thanks for the feedback. Guess I'll just put it back in like it was.

[Blue Stocking]

Originally Posted by Hodidoo

That nut and a liberal application of 5200 sealant will be more than enough

Hmmmm-really? Is that the consensus here? Mine each have 2, 5/16" bronze bolts, which also make good connection for my bonding #8.
Just asking.

[smurphny]

Mine each have 2, 5/16" bronze bolts, which also make good connection for my bonding #8.

That's exactly what I was thinking of doing. Do yours go through the hull or are they anchored in a block glassed to the inside? If that flange was engineered to be just kept in with the thruhull thread, it wouldn't have the bolt holes.

[pressuredrop]

my (2) 1-1/2" (tapered plug) seacocks are bolted with 4 (bronze) bolts each, my (2) 3/4" (tapered plug) seacocks did not have any bolt holes, so i did not bolt them, a liberal amount of 5200 and glassed in backing plates are good enough for me for those 2...

[Blue Stocking]

Originally Posted by smurphny

That's exactly what I was thinking of doing. Do yours go through the hull or are they anchored in a block glassed to the inside? If that flange was engineered to be just kept in with the thruhull thread, it wouldn't have the bolt holes.

My hull is about 3/4 - 7/8" thick, solid glass at the seacock locations. Used countersunk flat head strut bolts (unthreaded portion full 5/16"- unlike rolled bolts where unthreaded portion is less than 5/16") , into the glass, through the block, to the seacock. Set with 3M 101.

[smurphny]

Same here. The hull is very thick, around 3/4" at the intake. It would seem that a couple of small 5/16" holes trump leaving the thing unbolted. Think I'll just use round headed bolts w/ washers. Not worried about a little drag in my old boat.

[redhead78]

Google compass marine, I believe maine sail has an excellent article wf pics on the Groco triflange base, this is one of the best...Red

[smurphny]

Thanks Red, great site.