Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 15-07-2021, 18:48   #1
Registered User

Join Date: Jan 2017
Location: St. Louis, MO
Boat: 1980 Cape Dory '27
Posts: 152
Plastic Water Tank Cracked! How do I fix it?

Replumbing the boat today with new pipes, noticed a 3 inch crack in the side of the water tank, which is made out of white plastic. Anyone know the right way to fix this?

I don't know if it leaks---I have never filled the tank. But I'd rather fix it so it doesn't spring a leak when I'm cruising.
mikebikeboy is offline   Reply With Quote
Old 15-07-2021, 20:23   #2
Registered User
 
Jammer's Avatar

Join Date: Jan 2010
Location: Minnesota
Boat: Hunter 26
Posts: 2,429
Re: Plastic Water Tank Cracked! How do I fix it?

The way you fix it is you remove it and replace it with a new one, or two new ones, and the way the world works the capacity will be somewhat less because you won't be able to find one that quite fits the space.


The reason you do that is that your 40 year old water tank with a crack in it is made out of plastic that is now brittle and no longer flexible. Sure, you can try to patch it with G/flex, or try your hand at some plastic welding. Might work, but the experience of others who have taken that road is that the materials and equipment cost is high and the odds of success low.
__________________
Never ascribe to wisdom that which is adequately explained by good luck.
Jammer is offline   Reply With Quote
Old 15-07-2021, 20:43   #3
Senior Cruiser

Cruisers Forum Supporter

Join Date: May 2013
Location: Oregon to Alaska
Boat: Wheeler Shipyard 83' ex USCG
Posts: 3,162
Re: Plastic Water Tank Cracked! How do I fix it?

If you decide to fix the crack, drill a hole at each end of the crack. It relieves the stress that caused the crack. Grind out the crack to about 45 on each side so your patching material has more area to bond to.
Lepke is offline   Reply With Quote
Old 16-07-2021, 04:17   #4
Registered User
 
Orion Jim's Avatar

Join Date: Dec 2008
Location: Noank, Ct. USA
Boat: Cape Dory 31
Posts: 2,441
Images: 8
Re: Plastic Water Tank Cracked! How do I fix it?

The Cape Dory Board • View topic - Polyethelene tank repair
Two methods of repair discussed here….
Orion Jim is offline   Reply With Quote
Old 16-07-2021, 05:21   #5
Senior Cruiser
 
tkeithlu's Avatar

Cruisers Forum Supporter

Join Date: Feb 2012
Location: Carrabelle, Florida
Boat: Fiberglas shattering 44' steel trawler
Posts: 3,705
Re: Plastic Water Tank Cracked! How do I fix it?

Lepke speaks with wisdom. The crack is not necessarily the end of the tank, although it certainly could be. So, and assuming that you are not about to take off on a water-critical circumnavigation, you stop-drill the crack so it stops propagating, bevel, and glue. That's the simplist repair that is likely to work. In the process you'll find whether the plastic is brittle. Save drastic solutions (replacement, often a whole bunch of trouble) for when it is obvious that you need them.
__________________
Never let anything mechanical know that you are in a hurry.
tkeithlu is offline   Reply With Quote
Old 16-07-2021, 08:47   #6
Registered User

Join Date: Jul 2012
Location: North East USA
Boat: 1975 Tartan 41'
Posts: 846
Re: Plastic Water Tank Cracked! How do I fix it?

I'm guessing it is low density polyethylene, as most white plastic tanks are. Not many glues or epoxy will stick to it, BUT it is relatively easy to 'plastic weld' if you have access. There are a lot of youtube videos on it. I have found a micro torch and PE plastic tubing, pre-flatenned, to be a good combo for heat and fill. Electric irons don't work and heat guns (ok for pre-heating) don't have the precision. You could try pre-heating then a hot glue gun to fill the crack as well, but its not as good... Practice on an old cutting board before you attempt repair.
zstine is offline   Reply With Quote
Old 16-07-2021, 08:59   #7
Registered User

Join Date: May 2018
Posts: 67
Re: Plastic Water Tank Cracked! How do I fix it?

there's repairs and then there are "repairs"... me thinks this falls into replace (repair).... wee bit of research will determine your best course of action
arcticmonkey is offline   Reply With Quote
Old 16-07-2021, 09:12   #8
Registered User
 
bailsout's Avatar

Join Date: May 2013
Location: Morro Bay, CA
Boat: Herreshoff 28 modified ketch- wood
Posts: 348
Re: Plastic Water Tank Cracked! How do I fix it?

That boat is about the same size as mine. I removed my water tank and replaced it with gallon water bottles. Good moveable ballast! And they all can’t leak or get contaminated. I just use fresh water for solar shower bag, drinking, cooking and brushing my teeth.YMMV.
bailsout is offline   Reply With Quote
Old 16-07-2021, 09:14   #9
Registered User
 
bailsout's Avatar

Join Date: May 2013
Location: Morro Bay, CA
Boat: Herreshoff 28 modified ketch- wood
Posts: 348
Re: Plastic Water Tank Cracked! How do I fix it?

It also opened up some storage space and easy inspection/access to my chain plates for the mizzen mast. Removed and sealed deck filler fittings.
bailsout is offline   Reply With Quote
Old 16-07-2021, 09:15   #10
running down a dream
 
gonesail's Avatar

Join Date: Mar 2006
Location: somewhere in the deep south
Boat: cape dory 30 MKII
Posts: 2,465
Images: 6
Send a message via Yahoo to gonesail
Re: Plastic Water Tank Cracked! How do I fix it?

replace the tank. once they start cracking they are brittle and it only gets worse.
__________________
some of the best times of my life were spent on a boat. it just took a long time to realize it

gonesail is offline   Reply With Quote
Old 16-07-2021, 12:11   #11
Registered User

Join Date: Jun 2012
Location: Northeast Harbor, Maine
Boat: Cape Dory 31
Posts: 222
Re: Plastic Water Tank Cracked! How do I fix it?

Coincidentally, Practical Sailor had an article on repairing plastic water tanks some years ago. Sadly, the issue is at our other home in New Hampshire and we're now in Maine. You should be able to call them and ask for the back issue or maybe they'll just email the article for a small fee.

Tricky to repair, those polyethelene tanks. You need special glues. Also if the repair is low in the tank, may be better to replace it.

Good Luck
__________________
Jenn & Terry
North Conway, New Hampshire
Mahone Bay, Nova Scotia
jen1722terry is offline   Reply With Quote
Old 16-07-2021, 12:29   #12
Registered User
 
LeeV's Avatar

Join Date: Apr 2013
Location: Md
Boat: Lagoon 450F
Posts: 1,187
Re: Plastic Water Tank Cracked! How do I fix it?

We had that happen on one of our trimarans. We cut it, dried and smoothed it out and then inserted a flexible bladder using the old tank to hold it and brought the new neck/filler up to the same spot.
__________________
LeeV
Lagoon 450 F
Momentum
LeeV is offline   Reply With Quote
Old 16-07-2021, 13:49   #13
Registered User

Join Date: Jan 2017
Location: St. Louis, MO
Boat: 1980 Cape Dory '27
Posts: 152
Re: Plastic Water Tank Cracked! How do I fix it?

Wow thanks everyone. I think I'll try the gFlex + fiberglass

If that fails it fails. If it works then yay.
mikebikeboy is offline   Reply With Quote
Old 16-07-2021, 14:14   #14
Registered User

Join Date: Oct 2013
Posts: 213
Re: Plastic Water Tank Cracked! How do I fix it?

Quote:
Originally Posted by mikebikeboy View Post
Replumbing the boat today with new pipes, noticed a 3 inch crack in the side of the water tank, which is made out of white plastic. Anyone know the right way to fix this?

I don't know if it leaks---I have never filled the tank. But I'd rather fix it so it doesn't spring a leak when I'm cruising.



Almost impossible to make a successful long-term repair.
If it's near the top of the tank, a temprary repair with adhesive tape can work.
Yje melancholy fact is that you'll probably be better off replacing it sooner than later.
I'd check and see if it actaully leaks - sometimes they don't, until in a seaway.
chasfgr is offline   Reply With Quote
Old 16-07-2021, 14:21   #15
Moderator Emeritus
 
Hudson Force's Avatar

Cruisers Forum Supporter

Join Date: Nov 2008
Location: Lived aboard & cruised for 45 years,- now on a chair in my walk-in closet.
Boat: Morgan OI 413 1973 - Aythya
Posts: 8,347
Images: 1
Re: Plastic Water Tank Cracked! How do I fix it?

I was finally resigned to using LeeV's plan of placing a bladder inside my old white plastic water tank. I spent a couple of years trying to seal a crack at the top fill connection that would leak with a heel when the tank was full. I was limited with access and never made a good seal with my attempted repairs. I lost some volume with using the bladder tank, but removing and replacing the tanks would have required taking out my generator, refrigeration and more just to gain room for the refit.
__________________
Take care and joy, Aythya crew
Hudson Force is offline   Reply With Quote
Reply

Tags
water

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Exhaust Riser: quick fix and permanent fix options wyb2 Engines and Propulsion Systems 20 20-05-2018 11:10
plastic tank or bladder for holding tank? RSB333 Plumbing Systems and Fixtures 2 25-10-2017 11:37
How to weld/glue/fix cracked outboard engine plastic fuel tank? ErikFinn Auxiliary Equipment & Dinghy 31 06-10-2014 15:11
Cracked fiberglass hding tank Just us Plumbing Systems and Fixtures 11 08-09-2013 12:29

Advertise Here


All times are GMT -7. The time now is 03:51.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2021, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2021, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.