Water Tank Replacement

My tank had to be cut out - I have not heard of another way.
My settee base was cut 1" from the settee back/bulkhead and along the athwart-ship bulkheads. A 6' piano hinge was attached. To open and close, there's 2 screws locking it closed. Access is now quite easy. No structural harm done that I've noted.
One other thing to note - use a reciprocating saw like the Max Dremel. It will cut a fine line.

Bob: I've replaced the tank like Tony did except I fiber glassed the piece back in place. The first thing you need to decide is what type of tank you want to install. If it is a bladder tank, I would cut an opening on the aft end of the tank that is the size of a hatch that you intend to place there. I would then cut the plastic tank out in pieces and remove them through the hole you cut. You install the bladder and hatch to finish the job. This is how I would do it if I had to do it over. The internal glass unit is gel coat and smooth so a bladder should work well. If it does leak, open the hatch and replace the baldder. If you want a hard tank then your only option, as far as I can tell, is to cut out the old and install the new.

Jay

Well, we've learned a few things about water tanks and leaks.
1) You do have to cut to within one inch of the settee back to get the tank out.
2) You have to cut twice if you fail to follow 1) above.
3) It may not be the tank that leaks.
4) In my case it is the pex end fitting that failed after only 29 years.
5) The outlet plumbing (leaky pex end fitting) is buried so deep (under wire bundles and holding tank hose) that it can only be removed by cutting.
6) A rotery saw fitting on a dramel tool will fit in the hole to cut the outlet plumbing.
7) We have to learn plastic welding to fix the nick the saw made in the tank.
8) On the up side, don't need a new tank.



Tank Label




Where the wtr tank outlet lives




Where the tank lives

Wanted to add a bit Thank You to everyone who offered helpful advise and information.

Forgot to add the photo of the settee with the top off. That's how it should look to get the tank out.

Getting the tank out is a two person job.

One of those auto body suction gadgets is helpful making a handel to lift the forward end out of the hole.




Topless settee

I have. 1978 382 and there is a very slow leak in my starboard water tank. But, it does not leak past about 3/4 of the tank. Somewhere above that elevation is where the leak is. Any ideas?

Have you searched the Archives? Actually, there is good information in all the posts above.

I agree cut the top off the seat stay close to the edge and you will be fine. i put a piano hinge on the back and screwed it back after having the tank end replaced.. No leaks now,
Don't be afraid cut the top on 3 sides.. 1982 384 Wind Rose

When I bought my boat the PO said there was a leak in the the stbd water tank. Since I found all the tank connections loose and leaking on the port tank I assumed the same on the stbd. When we filled the tank for the first time the bilge pump came on. Needless to say we used just the port tank for the summer.
I removed the tank and and there was a 8 inch crack at the baffle. After doing research on th site it was suggested that the tank was made out of High Density Polyethylene. I did some more research and bought a plastic welder at Harbor Freight and cut up a 5gal bucket for the filler rod. After welding I filled it with water and for the rest of the day I chased one drop of water, I could not make it stop leaking.
The next day I call the manufacturer and asked them what material was used for the tank, Low Density Polyethylene was the reply. So I ordered the rod from Granger and a different welding tip that allowed me to feed the rod through the tip. After grinding out the HDPE I welded with the LDPE and with the first try I had no leaks.I also reinforced the site with stainless steel wire mesh from a food strain and put a second layer of plastic on.
For about $100 I was able to repair the tank.

Also WEST Epoxy makes a epoxy called Flex seal sorta very flexible epoxy meant for tank repair ! about 30 dollars