Fixing a cracked water tank

[Rich18864]

I finally figured out where all the water was going, when I was cleaning and refilling my freshwater tank (only used for washing, no drinking). Floating floorboards during the refill gave it away :cussing:. The pictures show where the crack is located. I'd like to repair the tank, if possible, so I need suggestions from those more intellectually (or experienced) blessed with a solution. I need to check the area in the compartment and see if there are any sharps area, etc. but it looks like a general crack or split. The boat has never experienced any freezing conditions, so I'm sort of at a loss as to why this has occurred. Thanks in advance.

 

[Pat]

Looks familiar.

I finally figured out where all the water was going, when I was cleaning and refilling my freshwater tank (only used for washing, no drinking). Floating floorboards during the refill gave it away :cussing:. The pictures show where the crack is located. I'd like to repair the tank, if possible, so I need suggestions from those more intellectually (or experienced) blessed with a solution. I need to check the area in the compartment and see if there are any sharps area, etc. but it looks like a general crack or split. The boat has never experienced any freezing conditions, so I'm sort of at a loss as to why this has occurred. Thanks in advance.

Our 272 has a leaky water tank as well. I'm not sure when it began leaking, but I know it has leaked for the last 10 years....I'm not certain who made the tanks for O'Day but ours leaks out of a crack in the top that runs parallel straight fore and aft along the inside top of the tank....would be starboard side of the tank, parallel w/the side wall. About 8 or so years ago, I realized I could just not fill the tank all the way up...and so that's what I have done, i.e. not fill it up...but if I put too much water in the tank, it will come out when the boat is healed to starboard as on a port tack...I'm thinking of pulling out the tank and using a smaller flexible tank, maybe 20 gallons in lieu of the 30....may also (maybe not) give us more room in the
port setee...since we are at a yc.in Wichita...we can get plenty of water for
free and fill up whenever needed for a night at anchor....Patrick

 

[Rich18864]

I wish I could get 20 gallons into mine, but since the crack is on the bottom, closest to the keel, I'm not going to have a chance to get one gallon into it. One thing a full tank does, for my boat, is balance it out at rest. Batteries and the o/b on the starboard add a bunch of weight on one side. The material used to mold the tank seems to makes it feel a bit "slick", so I'm not sure that packing the crack with some sort of sealant will work. I've considered melting some plastic and pouring it across the crack, but haven't settled on doing this. And, there's probably little chance to find another with the same dimensions. I like what JB Weld does with metal holes, but this is a different animal. Still can't imagine why it cracked; no UV rays, etc. Maybe one of the flex tanks is in my future, too. Thanks!

 

[Joe11688]

Devcon I think, makes a two part plastic epoxy that works very well. I used it just this year to fix my Gray Marine forward hatch and it works like a champ. I also used it to cement a cracked cap for a 6 gallon poly gasoline can a couple of years ago and it's still holding.

 

[Merlin Clark]

Might check out HDPE repair. I think most marine tanks are made of the same stuff as kayaks and milk jugs. Is there an embossed label somewhere on the tank?
HF carries welding kits for HDPE plastics. RONCO Plastics might carry a replacement. Their site says they have 500 to choose from.

 

[Rich18864]

Thanks for the suggestions. Regardless of what I use to seal the crack, I want to feel good that it will hold. 30 gallons is close to about 200lbs. in weight and the pressure of this weight will be at the bottom of the tank. Wish it was as easy as GE silicone, but that's probably not going the work. I'll do more research on HDPE repair and see what's suggested. I recall looking at the Ronco offerings some time ago (bored) but didn't see an exact replacement. The shape of this tank is odd, as it it made to fit in the space provided, with little in the way of options. Thanks! Rich

 

[Tori Taylor]

Weld on number 40 will repair the plastic crack. It is a commercial product and works much better than the weld on number 3 or 16. We fixed ours with it over 6 months ago no leaks so far

 

[Peter18046]

Cracked/Crumbling/Leaking O'Day Water Tank

Had the same problem in my 1976 O'Day 25: the tank held 13-gallons. I believe they might have been custom-made tanks for O'Day and were made of a soft polyethylene plastic, not unlike that old Tupperware plastic that was famous for degrading over time. I tried various cements and sealants for repair, but none held satisfactorily. With no safe repairs possible, I decided that I didn't want any degrading plastic leaching into the water system with the possibility of ingesting any of the chemicals. So I purchased a new Todd 15-gallon tank, the dimensions of which were only 1 inch bigger on length, width and height. And gaining 2 gallons of extra fresh water capacity was not to be ignored! The only difference from the original O'Day tank is that all openings, including the vent opening are on one end of the tank, which for my boat was the starboard side. I installed a plug on the side-fill opening and cut a Beckson 4-inch gasketed clear-cover inspection plate into the top of the tank to facilitate inspection, cleaning, and filling from the top. That left the vent and the exit fittings: Home Depot supplied the 3/8x1/2 inch brass barbed exit and tee fittings for the 3/8 hose plumbing system, and the 1/2x1/2 inch black plastic "funny" elbow for the 1/2 inch vent tube, which I ran forward along the starboard top edge of the tank to the bulkhead and then vertically as far as I could go. I could have used a 3/8 inch brass elbow for the vent if I had found one, but nothing like that was available locally, and I did check many sources. Only in the web did I find that elbow, and I didn't have the time for that. I simply followed O'Day's technique of glassing in the tank using two layers of 4-inch wide fiberglass tape, and used the same tape to provide lateral and fore and aft support at the corners on the base of the tank where it contacted the hull. And of course I took the opportunity of replacing all supply hoses.

 

[All U Get]

Re: Cracked/Crumbling/Leaking O'Day Water Tank

Hi Rich,
I used G flex on the bottom of a 50 gallon rain barrel and it worked perfect. Watch this video http://www.youtube.com/watch?v=2a5RlcP-4JE .
All U Get

 

[Rich18864]

Thanks for all the suggestions, especially the latest from AllUGet. I watched the attached video and the last of it was almost like watching an audition tape for "JackAss"!! Tossing a kayak off an overpass is major destructive testing. It's amazing that there are so many viewpoints on how to repair things and the reason I watch this website. Now, to make an informed decision and press forward. Happy Thanksgiving!!