Need to fix leak on fresh water tank

ktmrfs wrote:
many fresh water tanks are polyethelyne (white semi transparent). it is very very hard to get anything to stick to it. Your options are:

1) if the hole is small, drill it out and then insert one of the well nuts used for the sensors. quick and easy if you can get to it
2) have a repair shop with the proper equipment "spin weld" a patch on the hole. Basically your using friction from the spinning patch to melt the plastic. that is the factory method to attach fittings to these tanks and probably the best long term solution. Most any RV dealer will either be able to spin weld a patch or give you the name of someone who does this.

X2

I spoke to a tank manufacturer and he said that the plastic used for tanks was formulated in such a way that nothing sticks to it permanently. Some products may work for awhile but will eventually fail.

Polyethylene plastic welds great if you know how to do it.

Jose

I would get a screw about the same size as the hole or a self tapper screw a little bigger and insert it into the hole. A little silicone or the like on the screw head or even a piece of rubber to help the seal. Works for plastic gas tanks so I am sure it would work for a water tank.

This is common knowledge in the prepper community. If the world every falls apart and you need gas for a genny just take your drill and a few self tappers, poke a hole in your gas tank and take out what you need. When done run the screw back into the hole to seal it up.

I love JBWeld and use it for a lot of things, but it doesn't work that well on a lot of smooth plastics. A lot depends on the size of the hole. I would try to repair a small hole with a screw and a good plastic adhesive/sealant.

The hole is about 1/8 to 3/32 inch is size . I will try the easy
ways first and work my up the drilling and inserting some mechanical
plug. thanks

many fresh water tanks are polyethelyne (white semi transparent). it is very very hard to get anything to stick to it. Your options are:

1) if the hole is small, drill it out and then insert one of the well nuts used for the sensors. quick and easy if you can get to it
2) have a repair shop with the proper equipment "spin weld" a patch on the hole. Basically your using friction from the spinning patch to melt the plastic. that is the factory method to attach fittings to these tanks and probably the best long term solution. Most any RV dealer will either be able to spin weld a patch or give you the name of someone who does this.

Near our town there is a company called "Industrial Plastics and Paint". If you have something like that near your place, I would suggest you call them.

I would imagine drilling the hole round, then threading it and putting in a plastic plug either with epoxy or with teflon tape would be the best solution.

You may have to start with a larger patch to give you enough wall thickness for the threads to have enough to bite into, but I am very sure a marine shop or a plastics company will have an answer for you.

Moved to Tech Issues forum from DIY.

I had to replace mine after an attempt at plastic welding. Probably best to skip the repair attempt.

mbopp wrote:
Define "small." 1/8"? 1/2"? A 3" gash?

x2