Has anyone had a plastic fresh water tank welded?was it successful and was it a fairly new or an older tank.I had a blowout and it cracked the fresh water tank on my 1990 Southwind. I am told it can be welded but some welding forums suggest that an old tank will get brittle and "DRY OUT" and the weld will not last.Any input appreciated.If you know of any place in Nashville TN, Jackson MS and then down I55 to I10 to Beaumont that does this, their name would be nice.I did Google it; I am looking for recommendations for a place to go

I have never done business in the area you are in, but you want to get on Thomas net. The companies you want do not generally do business with the general public. So, they won't have websites or yellow pages ads. The tank is probably polyethylene and it can be welded if it has not been in the sun. Matt

Harbor freight tools had a plastic welding kit I have always wanted to get one, have not had the need yet I hear they work well I have only seen pvc welded with it though. good luck

More than likely it is ABS. That means you can solvent bond it. If you can find some ABS sheeting, you can use ABS pipe solvent and glue the patch over it. That will be much stronger than welding, and you are much less likely to get it too hot and damage the molecular structure. I have welded an ABS tank, but I was using an ultrasonic welder, which allowed me to press the rod into the crack. That worked very well, but I had a lot of control of what I was doing, much more accurate than a hot air welder.

Repairing polyethylene or polypropylene can be problematic. The age is definitely a factor as the plasticizers tend to disappear either due to chemical bonding or evaporation leaving a brittle material. It can be welded with a heat gun but you have to be very careful about temperature as it will go from tacky to very soft quickly. A backing material to support the soft plastic would assist the procedure. If you need patch material to build up the repair site getting a compatible melt index is close to impossible, unless your able to cut off a piece of excess material elsewhere on the tank. I do not know of a satisfactory glue for use on poly. You might be able to fix using cover plates with 5200 and riveted together. I have repaired holes and cracks in plastic kayaks but its ugly work. And additional cracks eventually recur. pops

Use EternaBond tape here are instructions.RV fresh water tank repair

welding plastic resh water tank | Good Sam Community

dtgunner7
Explorer
Nov 23, 2013
As I said DON'T waste your time and money.. Cracked tank not like new water, dirt, minerals, and who wanted to drink or use water from a tank that you just stirred up all kinds of chemicals used to make the tank
Bill_Satellite
Explorer II
Nov 23, 2013
You can't go wrong with that solution. You will now have great peace of mind and a dry bay for years to come.
darsben
Explorer II
Nov 23, 2013
Bill.Satellite wrote:
There's a huge difference between welding in a tank sensor and trying to weld a crack in a tank. My crack ran across the entire top of my fresh water tank (163 gallon tank) which had multiple baffles (indentations) and I had a professional do the repairs. It did not hold and I would doubt anyone could have made it hold. Others may disagree and that's certainly their prerogative. I ordered a new tank (no welds/seams in my new tank other than where a sensor or fill/drain was installed) and I have never looked back or been disappointed in the decision I made. The leak from the tank was long term and destroyed the floor in that compartment. If you have ever had to pull everything out, replace and waterproof a floor and then replace the black/gray/fresh tanks you are going to want to ensure that you NEVER have to do this again. For me (me, not you) that meant I did not want to go the temp. repair route. I wanted it to be a fix that would last the duration of my ownership.
YMMV

That is why I went with a new tank. When no one will guaranty there work then I worry. My crack is on the bottom and if it leaks it could be a long time before it showed up. New I feel better
Bill_Satellite
Explorer II
Nov 22, 2013
There's a huge difference between welding in a tank sensor and trying to weld a crack in a tank. My crack ran across the entire top of my fresh water tank (163 gallon tank) which had multiple baffles (indentations) and I had a professional do the repairs. It did not hold and I would doubt anyone could have made it hold. Others may disagree and that's certainly their prerogative. I ordered a new tank (no welds/seams in my new tank other than where a sensor or fill/drain was installed) and I have never looked back or been disappointed in the decision I made. The leak from the tank was long term and destroyed the floor in that compartment. If you have ever had to pull everything out, replace and waterproof a floor and then replace the black/gray/fresh tanks you are going to want to ensure that you NEVER have to do this again. For me (me, not you) that meant I did not want to go the temp. repair route. I wanted it to be a fix that would last the duration of my ownership.
YMMV
DanTheRVMan
Explorer
Nov 22, 2013
My tank had a crack when tiffin did the wet bay repair. They tried to repair a few times and gave up. A new tank was the only solution.

I do not know what it was made of or the repair method as I was not paying a lot of attention.
joraz
Explorer
Nov 21, 2013
I've (unfortunately) had some experience with a cracked tank. In my case, it was the black tank. I had it professionally welded but it didn't work. Later, I discovered that my tanks are Crosslink Polyethylene. These tanks cannot be repaired and must be replaced. My tank is an unusual configuration but that's another story. Bottom line: If it's crosslink PE, start lookin' for a new tank!
jor
bluwtr49
Explorer II
Nov 21, 2013
It's been awhile but I've had many tanks plastic welded to install spigot, fill old holes, and etc. The vast majority were PE and many were way over 1,000 gallons. Simply never been a big deal. You just need to find the right house.

On the other hand, it's also easy to find places to custom make the tank just by taking in the old one and waiting a few days. Nothing about them should be expensive unless there are some oddball contours and etc.

Virtually all tanks are welded when assembled so poo-pooing welding as a generic statement doesn't fly. Granted there may be some issues with a tank where any repair is contr-indicated but finding a good plastic house would be my first stop.
wa8yxm
Explorer III
Nov 21, 2013
Everyone has had a fresh water tank welded.. How do you think they installed the sensors.. And yes, it worked.
Daveinet
Explorer
Nov 21, 2013
Tank Depot should be a lot faster than that. I think mine was less than 2 weeks. They installed fittings to order.
darsben
Explorer II
Nov 21, 2013
I am going to replace the tank. The professionals I spoke to would NOT guaranty their repairs at all. I tried to find a used one and called both COLAWS and VISONE.

Colaws will not sell used tanks and Visone was most unprofessional after 4 - 5 days of talking on the phone I gave up. All Visone gave me was a bunch of empty promises about a call back to let me know if they had the part.

Ordered part and delivery is four weeks away. Thanks for the info