Can’t Connect Hose to Seacock

Aug 24, 2020
Beneteau Oceanis 321 321 Little River, SC
So, I replaced the toilet on my 32’ sailboat with a brand new Jabsco and decided to also replace the intake hose. It was very old & smelly and I didn’t want to contaminate my brand new bowl. I picked up some Shields Series 148 VAC XHD hose from West Marine to replace the old one.

I was able to connect one end of the hose to the Jabsco toilet with great difficulty using a heat gun and brute strength. But I have now spent 2 days trying to connect the other end of that same hose to the seacock. Nothing works. I have already destroyed a few inches of the hose in 2 heroic attempts to no avail. In one case I had to bend the hose back and forth so much to try and get movement that I split it on the seacock.

Now I consider myself a fairly handy guy but I just don’t see how this hose is going to fit on the seacock. I think it’s a Blake seacock and it is a bit oversized. I tried the heat gun while turning the hose against the direction of the metal spirals and can get nowhere. I tried every trick I read online & nothing. It’s literally like trying to fit a square peg in a round hole. I have checked 3 times to make sure the hose size is the same as the old one (3/4”) and double checked the seacock size. It’s all the same. I’ve even measured the hose itself just to make sure. It’s 3/4” alright.

Part of the problem is that the seacock is in a tough spot. It’s at a right angle with the sink drain seacock right next to it and it’s close to the cabinet wall. But still, I should be able to get the hose on. I have heard about how hard it is to get extra heavy duty hose on a Blake seacock but this is ridiculous.

So now I have to decide what to do here. My first option is to just start from scratch and disconnect the new hose from the toilet (which I am wary of doing because it was so tough to get on) and try a lower grade hose. After all, I don’t need extra heavy duty hose for the toilet intake. In fact, I think Shields makes a Series 148 multi-purpose hose (not extra heavy duty) but I’m not even sure that’ll be any easier to get on and I have to find it to buy it.

My second option is to somehow clean & deodorize the old hose and just put it back on. But I honestly don’t think there’s anyway to clean & deodorize the old hose at this point. Otherwise it is in fairly good shape but the inside is just filthy. I’m very wary of this option - after all, that’s the whole reason I’m replacing it.

Lastly, the third & preferred option is to somehow figure out a way to get this hose on the seacock without destroying it in the process. The problem is that’s what I’ve been doing for 2 days and I’ve gotten absolutely nowhere after a lot of work & time.

I’m curious to know what you all think and if anyone has any suggestions. As I’ve said, I have tried a heat gun, dawn liquid to grease it, turning the hose against the direction of the spirals to open it, a strap wrench, tried tapering it, etc. all to no avail.
Jan 7, 2011
Oday 322 East Chicago, IN
a few ideas (use at your discretion)...

1). Dip the end of the hose In Boiling water to soften it
2) Lubricate the end of the hose with some soap or other lubricant
3) grind/sand down the barbs on the fitting little to help get the hose on.

I have used all of these on one hose I replaced this year.

Aug 24, 2020
Beneteau Oceanis 321 321 Little River, SC
Greg - I hadn’t thought to grind down the barbs a little on the fitting, that’s a very interesting idea and might just work in my case. Obviously great care should be taken and I’m a little wary of doing it but it’s a great idea. Thanks, will let you know if it works


Feb 12, 2019
beneteau 461 port colborne
Don't grind anything down. Just use boiling water. If you can't dunk it in the water just boil a kettle and slowly pour it on the hose. So much better than a heat gun.
Aug 24, 2020
Beneteau Oceanis 321 321 Little River, SC
I’ll give the boiling water a try but this is the first that I’ve heard it’s better than a heat gun. I got nothing to lose trying it though.
Jan 11, 2014
Sabre 362 113 Fair Haven, NY
Clean and lubricate the hose barb. Dish detergent works, a water based lube works (KY-Jelly).

Heat the hose in hot water. Then insert a tapered plug into the hose to stretch it, remove the plug and stick it on the lubricated barb.

A heat gun heats the outside the hose, a pot of hot water heats the inside and outside of the hose. A tapered plug gradually stretches the hose.

Overheating some hoses makes them stiffer when they cool.
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Oct 22, 2014
CAL 35 Cruiser moored EVERETT WA
:plus: With @dlochner.

I would not grind anything.

Silly question, you measured the hose inside diameter and matched to the barb size?
Dec 2, 1997
- - LIttle Rock
If, as you suspect, the fitting is a Blake, you're trying to put a 3/4" hose onto a metric fitting that's just enough larger to make it impossible. Stretching the hose is a bad idea because over-stretched hose will quickly start to develop tears in it.

A solution that solves more than one problem: Instead of connecting the new intake line to the intake seacock,
re-route it to tee or wye it into the sink drain line as close to the seacock as possible because the connection must be below waterline to work.

This will allow you to flush normally with sea water. After you’ve closed the sink drain seacock in preparation to close up the boat (you do close all seacocks before leaving the boat to sit??), fill the sink with clean fresh water and flush the toilet. Because the seacock is closed, the toilet will draw the water out of the sink, rinsing the sea water out of the entire system—intake line, pump, channel in the rim of the bowl and the discharge line,(Water poured into the bowl only rinses out the toilet discharge line). If your toilet is electric, be careful not to let it run dry…doing so can burn out the intake impeller. Or you can keep the sink drain seacock closed except when it's needed to drain the sink and flush with fresh water down the sink all the time...your choice. This also makes winterizing much easier...after you've pumped out and thoroughly rinsed out the tank, just pour the antifreeze down the sink--with the seacock closed, of course!
It may also be necessary to keep the sink plugged except when in use, with a rubber sink plug or by installing a conveniently located shut-off valve in the drain hose. Otherwise the toilet may pull air through the sink when you try to flush, preventing the pump from priming.

A lot of people have done this since I first began recommending it in the mid-90s after I found out that some builders plumbed their toilets this way.

Aug 24, 2020
Beneteau Oceanis 321 321 Little River, SC
Yes, I measured the diameter of the hose. It is definitely 3/4”. I’m actually working on it right now and it looks like using a tapered wooden plug is doing the job. I cut a few inches off my wife’s plunger which happened to have a 3/4” wooden handle and sanded it down a bit to taper it more. I’m heating the hose with heat gun and am able to get the plug in an inch or more so I’m right there. The tapered wooden plug is by far the easiest method so far and seems to be working. I will post shortly if I am successful.

I do believe the seacock connection is 19mm which technically is just under 3/4” (.748”) so I don’t think that’s the problem. But let’s see. I did stop by West Marine this morning and picked up some different grade hoses just in case (plus it’s always good to have spare hoses for emergencies). I will try one of those if I can’t get this one on.

Will post shortly as to whether I’m able to get it on the seacock but it’s looking good so far.
Aug 24, 2020
Beneteau Oceanis 321 321 Little River, SC
Peggie - to be honest I think the problem is that the hose is actually 19mm and the seacock is 3/4”. If the hose were a full 3/4” then I should be able to slide a 3/4” plug right into it without stretching it yet there is no question that the plug is stretching it. I don’t want to connect it to the sink. To be honest at this point it would be as much work to do that than just finish the job I started.
Aug 24, 2020
Beneteau Oceanis 321 321 Little River, SC
SUCCESS!!!! Ok, I finally got the hose on the seacock! At least far enough - past all 4 barbs which should do the trick. The tapered wooden plug with heat gun and dishwashing liquid for lubricant did the trick.
That was by far one of the worst jobs I’ve had to do. Now it’s time to replace the sink drain hose which will be a snap since I finally figured it out. Thanks everyone for the great tips! Especially the tapered plug.