Thru-hull fittings

jrp4783 · 04-09-2012, 09:40 PM

A friend of mine asked me the other day why some of my thru-hull's have fittings and some don't. Please see pictures from my 2000 50' Post. My simple answer was that I did not know. The boat has been painted and I wondered if this is normal or that it was not put back together properly. Anybody out there that can enlighten me? Thanks.

AlfredZ · 04-09-2012, 09:53 PM

Hi there,

There is something wrong for sure, you should have a fitting on any whole on your boat. As you can notice in the first pic, the core material of your hull is exposed, this is bad to say the least! From the looks of it, I guess the fitting is broken (you can see a black rim inside which is a pasrt of the lost fitting). You have to solve that before you put your boat back to water, it has to be sealed and installed properly so you do not soak the core material or let the water reach where it should not. The other side should also be checked and have a proper seacock.

Cheers,

Alfred

Capt J · 04-09-2012, 10:16 PM

Your thru-hull is broken off and the only thing holding the hose and discharge going out of the hull instead of possibly sinking the boat, is the 5200 they installed it with. Plastic thru-hulls get brittle with age and it looks like yours should all be replaced.......

mwwhit1 · 04-10-2012, 10:04 AM

That is actually normal for a Post. They have been installing some of the above waterline thru hull openings like that since the 70's. I think for the most part they used full bronze mushroom fittings for the outlets that pump water (A/C, bilge\shower\fishwell pumps.) For sinks and drains there is a pipe pressed\bedded flush with the outside of the hull. I can only guess they did this for looks. No issues with mine done this way, going on 28 years. But I agree it is not the best way to do this.

jrp4783 · 04-10-2012, 11:29 AM

Thanks MW - I also had sent a few pics to Post to get their viewpoint. I'll post their reply once I get it.

jrp4783 · 04-12-2012, 08:40 AM

I discussed with Post and they said they purposely designed the thru-hulls that way for better appearance. They claimed that this technique has been reliable. Somehow the pipe is threaded into the hull. I need to look into this further.

Pascal · 04-12-2012, 09:08 AM

Threading the pipe in the hull??? What material is used for the "pipe"? Is the hull cored?

Sorry I don't buy this... You can't thread a fitting in fiberglass

And what s with these scoops just forward, is it to prevent back flow? Why? There should be loops. Odd set up

jrp4783 · 04-12-2012, 09:45 AM

I agree this is a strange set up. Could you have a threaded fitting (maybe made out of bronze) molded into the hull then have a threaded pipe from the inside screwed into this fitting? The hull is solid below the water line and foam cored above. Unfortunately I didn't spend a lot of time looking at the set-up and just took a quick picture.
Any other Post owners out there know how this is set-up?

RT46 · 04-12-2012, 09:46 AM

Post and several other boats have some through hulls glassed in flush to the hull....

its hard for me to tell from the pic, but the pic doesnt look clean like it was glassed in, it looks broken.

i think the picture in the OP shows that there may have been a plastic or nylon thru hull that the outter portion has broken off.

I would want to see what it looks like from the inside and i would repair or replace this asap.