Plastic Water Tank Repair

[dje67]

Plastic water tank on a Bene 36cc - the boss for the inspection hatch has separated slightly from the top of the tank causing water to leak when the tank is full. The crack is at the 3 o’clock position on the photos attached below the threaded boss.

I’m looking for repair suggestions…. I could just try to fill the joint area with, say, CT1, or cut off and re-seat the whole boss. If I do the latter, any suggestions for adhesive, noting the there is some flex on the tank top.

I’m not keen to apply any sealant to the inside of the tank as this might contaminate my drinking water.

 

[Boater Sam]

Weld it with a soldering iron? There is not an adhesive that will work well on that plastic I fear.

 

[Boathook]

If the tank is PE nothing will really stick it down. Might be best to cut the threaded bit off and bolt a hatch in place such as Custom Tank Hatch Plates | Tek-Tanks .

 

[Praxinoscope]

I have fairly successfully repaired PE using a hot glue gun, as there is not really any thing under pressure this may be worth a try, maybe combine boater sam’s soldering iron suggestion as well.

 

[ylop]

Its fairly easy to "plastic weld" with a soldering iron, or better still a tip you can add to a soldering iron thats made for the job (ebay plastic weld). You can buy plastic welding "rod" but for a one off repair you can cut strips from a milkbottle.

Getting some things that works is easy.
Getting something that looks pretty is much harder - but doesn't matter to you.

 

[peter gibbs]

Weld it with a soldering iron? There is not an adhesive that will work well on that plastic I fear.

You could talk to eg Tek Tank mfrers. Give yourself thd best chance of a permanent and sanitary solution.

 

[coopec]

Plastic water tank on a Bene 36cc - the boss for the inspection hatch has separated slightly from the top of the tank causing water to leak when the tank is full. The crack is at the 3 o’clock position on the photos attached below the threaded boss.

I’m looking for repair suggestions…. I could just try to fill the joint area with, say, CT1, or cut off and re-seat the whole boss. If I do the latter, any suggestions for adhesive, noting the there is some flex on the tank top.

I’m not keen to apply any sealant to the inside of the tank as this might contaminate my drinking water.

Can you take the tank out and get it welded by professionally? (Some of those adhesives can be toxic so be careful)

Welding Polyethylene

 

[seumask]

How about a piece of tap applied to the inside of the crack!
I DIY repairs to plastic of this type by drilling a series of small holes either side and sewing them up with whipping twine, then sealing with sikaflex. Probably a bit Heath Robinson for a water tank!

 

[dje67]

Seem to have successfully carried out a repair using hot glue. I cut the crack a little wider with a multi tool blade. I then used a heat gun to get some extra heat onto the repair to help the glue ‘flow’ before setting, then injected the hot glue into the gap. I also bought some BT1 (similar to CT1) and lined the outside of the crack for a bit of additional sealing. I’ve since been out in a couple of 30kn+ sails which gave the tank (and me…) a good sloshing, with no leakage.

 

[lustyd]

More importantly than leaks, how does the tea taste now?

 

[Daydream believer]

Loctite make the sealant for this application
loctite

 

[Scubadoo]

I had a similar issue with my dinghy outboard internal fuel tank where a crack developed in the thread. I used milliput epoxy (white super fine) and it worked well. When I found a very minor leak in my shower pump sump box due to a crack in the spigot, again used milliput and no further leaks. The great thing about the epoxy is to apply very wet to mould exactly how you want it and then let it dry hard. I also like others suggestion of using hot glue.

 

[ean_p]

Plastic water tank on a Bene 36cc - the boss for the inspection hatch has separated slightly from the top of the tank causing water to leak when the tank is full. The crack is at the 3 o’clock position on the photos attached below the threaded boss.

I’m looking for repair suggestions…. I could just try to fill the joint area with, say, CT1, or cut off and re-seat the whole boss. If I do the latter, any suggestions for adhesive, noting the there is some flex on the tank top.

I’m not keen to apply any sealant to the inside of the tank as this might contaminate my drinking water.View attachment 153951View attachment 153952

Buy one of these and weld it yourself..........
Leister Triac S CH-6060 Hot Air Gun - Plastic Welding / Flooring 1600W 120V 14A | eBay