OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Briggs & Stratton Engines Quantum Briggs and Stratton Fuel Tank Leak at Seam

It is a Polyethylene plastic fuel tank leaking at the seam and I am told absolutely nothing will stick to it. I saw a post by a plastic welder that said it is almost impossible to plastic weld as well. He did suggest trying to weld using some polyethylene from scrap but success was unlikely. I think the fuel tanks were subject to a recall by Briggs and Stratton many years ago but I think their generosity has expired by now. So, any suggestions as to how to fix them as I seem to come across a few like this - I have two here now. I have tried 2 part epoxy but it peels off soon after the petrol is added. Can last a week or two if lucky. Hot melt glue also peels off after use. Various glues, araldite, muffler putty, gasket glue etc.

I was thinking of this stuff from "Supercheap" - DynaGrip Plastic Tank Repair Kit (Plastic tank repair)

Have any of you guys successfully repaired these tanks and what did you use?

I plastic welded a Victa fuel tank a while back with my soldering iron, worked well. Nothing to loose.... try it and put some fuel in to test....
Make sure it is clean and dry....

Bodgee another fuel tank to the mower..
cheers
speedy

PS. Ensure that all traces of fuel are removed and cleaned out of the tank prior to using any soldering iron on the tank.

Yes HDPE plastic is extremely hard to bond as it is highly chemical resistance. There one product out that can do it but way too expensive even a regular mower shop to obtain. Now big factories either sonic weld these tank or use this hazardous chemical that they can get fairly reasonable priced due to the pure volume they would be using it in.

As Speedy suggested, plastic welding does work as long as you use the same plastic and don't over heat it. Over heating of the plastic is the main reason for welds failing as it makes the plastic brittle, but it would much easier to find a good used tank or purchase a new one. For those of us with shops it is also a liability issue as well, for if your welds don't hold and things do happen then you can be sued for damages.

Of all things don't use an open flame even around an empty tank. Just don't want the boom over here.

Sorry sparker I have a stack of quantum tanks here but postage makes it not worth the effort

Yes, many have tried but unsuccessfully i might add.
There is pretty much nothing out there that works, mainly due to the vibration of it sitting directly on a running motor.
The cheapest (and more commonly the best) option is to replace the tank with a good used one.
Cheers, Ted

I have tried welding with HDPE using a heat station and the results had everyone rofl. The recall of these tanks pretty much says it is a hopeless task to attempt repair. NormK, I agree postage is a deal breaker and now they're contemplating making it even more expensive by an additional charge for biosecurity screening.
A shame to throw away a tank that just has a leak. A leak that can't be fixed.
Thanks guys.

Sparker it does takes a lot practice and patience to do quality welds using heat but I have also been doing it for years too so I have a lot practice doing it. At first it was horrible looking and had a lot of failures. It when you're repairing tiny plastic springs you really got to be good at it.

Hi AVB, I think it is a skill that needs a lot of patience and at 70 years old I'm too cranky and crotchety. On the other hand.......I might have another go.........

Sparker I can check how much the postage is if you want me to, just have to make sure which Quantam tank you are after, they vary a bit. I posted a small motorcycle tank to a mate in country Vic just before Christmas and that cost $26

I wish I read this thread earlier. You won't believe this but I was told this trick by a backyard mower repair man a few years back and it worked on a plastic B&S fuel tank of mine.
Are you ready?
Nail polish. Common nail enamel for two bucks. Paint it on and let it cure for 24 hrs and that's it. He told me petrol won't touch it once its dry. I suggest you clean the work with some brief sanding and prepsol, though I forget if I went to that trouble. Not a drop came out.

Well there you go, I might just go split a tank to see how it goes.

Solved problem with good sexy looks to match.

Win win situation I'd say.

The "beauty" is you can select a matching colour!

"Yes darlings you can !"

Lol, you guys, your LGBT is showing. I got a used tank for $20. I will try the nail polish trick on one of the others. Have to do it when the wife's gone out.

I was told to get my own as I did get caught using mine wife's Purple Passion nail polish. Then she went through the work bench. She found a couple Bobbie pins, a tiny knitting needle, a pair panty hose and then; I had a lot questions to answer after all the yelling was done. I thought I was going to need to turn on the exhaust to clear all that smoke coming out her ears. And I did buy own stuff because of it; although, I do get surprise inspections yet.

We do use things not thought of by others at times. Now I do avoid duct tape. I don't think it works too well holding on bar blades; although, I did have one customer to try it.

I got caught too. But guess what: she doesn't have any nail polish! Then i was lectured about the damage to her nails from all the work I cause etc. etc. I'll get my own too but hide it in a secret stash in case any of the lads see it.

Now just think of all the pestering I got for having a jar Vaseline on my work bench when I did office equipment repairs.

Vaseline.....equipment repairs.....lol.

This is handy to know. lol!

Generally once a tank starts leaking I get so frustrated trying to repair it I end up chucking it in the bin and forking out $ for a new one.

Now if only there was an easy way to repair old metal tanks! I've used poly-weld, but find it is only a temporary fix. I thought I had completely repaired a tank one time, but 6 months later it started leaking again. Maybe I should try painting the entire can in nail polish. lol!

I'm not game to use the welder. "Flush it out thoroughly, leave the cap off and fill it up with water and go outside the shed", they say, and "you'll be right". Yeah mate, but I still don't trust it, and my welding is bad enough as it is, without trying to dodge water and fuel fumes.

I have welded up countless numbers of motorcycle fuel tanks and never have a problem with them, you just have to ensure you have cleaned them properly with liquid soap and flush at least 3 times and they are not an issue. I have found over the years that I have to cut the rusted section out, make up a repair patch, bronze that in and then a wipe of silver solder over the top because I have no idea why but I will always end up with a pinhole in the bronze no matter how smooth it flows on. Then put petrol in it and blow in the filler cap to pressurize the tank to check for any weeps. If I end up with a weep it is go through the whole flushing/cleaning process again.

The flux was the culprit. Been there done that on other tanks except I prefer to using air pressure and a water bath or soapy water sprayed all over for testing.

Also sounds you used the soft silver solder and not the hard stuff. The hard silver solder takes an ACE/OX torch to get hot enough to work on large pieces.

I took my leaky mower tank to an engineering works in town to ask if they could repair it. The bloke behind the counter backed away and said "Definitely not! That thing is a potential bomb."

So I took it to an old bloke who does welding and soldering in his back yard. He is a very good welder and I've got him to weld many things in the past. I showed him the tank and he backed away and said "No way I'm touching that thing!" He added "I will weld anything except fuel tanks." Then he told me how to weld it safely myself.

Clearly this is something you have to do yourself and "at your own risk". lol! The tank is still sitting in my shed.

Why not test it with a flame after washing it out? If anything ignites, it won't after that. Those two sound paranoid.

G'day All,

Please tell me you're joking Mowerfreak, please!

I had a client who is now dead, tried to weld a tank and was thrown against the wall of the shed by the explosion! Was taken to hospital but died some days later. In his thirties, had small children.

Welding of tanks can be and is done by people who follow proper processes which typically includes steam cleaning and nitrogen purging but SHOULD NOT be done by people not trained in such things. NEVER!

Cheers,

Totally agree prd. And I have welded tanks with ACE/Ox torches. Even the unburnt gases from the torch can build up in the tanks and become an explosion hazard as they do ignite later. Enclosed spaces always invites this hazard. An empty tank can be a lot more explosive than a full tank. This is why those of us that cut things like propane tanks fill them with water to limit the hazard but they do great BBQ grills once we safety open them up.

As NormK said the tank must be cleaned properly plus I would add well vented or water filled to do repairs. Even those tanks with the foam type baffles can still be very dangerous.

Sorry, but we all need to use our heads and stay safe. With things like this, we just don't need to take chances with.

I add this too as the following is what happened when someone uses duct tape to repair a fuel line. Believe or not it was a so-called professional shop that did this to the customer.

Hmm, maybe best to replace that dripping fuel tap after all.

I have been repairing/welding up petrol tanks for over 50 years and never had a problem, you just have to be careful and flush them out very well. And MF you are right after I have flushed the tank before I get close I always wave the oxy above the filler cap, that way you cab be sure you can get up close to it to work on it.
AVB when I say silver solder I am referring to the 5% silver type that is used for welding copper pipe, not the 50/50 soft solder used on tin, this stuff is not suitable for repairing petrol tanks but many have tried, sort of works sometimes

G'day All,

Please explain to me how waving a torch over the top of the filler point is in any way safer/ less explosive or dangerous than the actual welding process?! If the thing goes off you're only very slightly better off being at arms length from the thing as opposed to standing over it!

I don't think we should be posting stuff here that in any way encourages readers to start mucking around trying to weld repair tanks. It should not be done by anyone who doesn't have PROPER training in such things. People have been KILLED doing this!

Similarly I've long since banned people at work taking old 44gal drums home (we get bulk oil in them and often they are then used to store fuel) as there is a fair chance someone will try opening up one to make a .....whatever. Same thing. People have been killed doing this!