Repair Plastic Fuel Tank on M7060

[BFaronni]

Long time reader, first time poster here.

Hoping someone has successfully repaired their plastic fuel tank and can share how you did it. I have a 2021 M7060 with a punctured tank that I tried plastic welding using an HDPE welding rod. It seemed ok but started leaking after about 4 uses of the tractor. I re-did it a second time thinking I must not have heated it enough but got the same exact result. Now I am wondering if the tank is not HDPE. I tried calling the dealer to find out but they did not know and Kubota customer service would not tell me because it is 'proprietary information'. The other option I looked into was JB Weld but they specifically state none of their products are rated for contact with fuel. Has anyone had success repairing their plastic tank? If you used a plastic welder, what type of welding rod did you use? Any other success stories out there? A new tank is north of a grand, not including shipping, so I would really like to get the one I have repaired versus replacing it.
Any help or suggestions welcome.

 

[007kubotaguy]

My local radiator shop repairs them for me.

 

[DONLI]

My local radiator shop repairs them for me.

Marine tec two part epoxy, I have repaired many things with, including carbs, and plasitcs.

Don

 

[BFaronni]

My local radiator shop repairs them for me.

Thanks for the suggestion. Not sure if there is anyone in town that repairs radiators but will ask around. I would prefer to repair it myself only because taking it to someone means dropping the tank. It is do-able, just more work. The puncture is right in the front of the tank so is very accessible.

 

[BFaronni]

Marine tec two part epoxy, I have repaired many things with, including carbs, and plasitcs.

Don

Is this it? https://www.amazon.com/Marine-Tex-W...B003E1SGD0/142-5998739-0214624#productDetails

 

[North Idaho Wolfman]

Diesel tanks are a mix of several layers of material mainly PP ( polypropylene )

Trying to heat weld PP is pretty much impossible to do.

How big is the hole?
If it's not too big and not torn you might be better of using a plug patch.
Stainless Toggle bolt and nitrile rubber patch.

Or use epoxy patch like this.

Amazon.com: Blue Magic 6522KTRI QuikSteel Plastic Tank Repair Kit , White , 2 ounces : Automotive

Buy Blue Magic 6522KTRI QuikSteel Plastic Tank Repair Kit , White , 2 ounces: Putty - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

[lugbolt]

depends on the material it's made of.

I work with a lot of polypropylene and NOTHING sticks to it. Nothing! We have used everything, then called 3M and got in touch with an engineer to find a sealant that would stick. Nope. Polypropylene is the absolute worst material to repair, according to them. I would agree based on my experience.

Plastic is usually marked as to what type it is. PP is polypropylene, PE=polyethylene, etc.

 

[McMXi]

depends on the material it's made of.

I work with a lot of polypropylene and NOTHING sticks to it. Nothing! We have used everything, then called 3M and got in touch with an engineer to find a sealant that would stick. Nope. Polypropylene is the absolute worst material to repair, according to them. I would agree based on my experience.

Plastic is usually marked as to what type it is. PP is polypropylene, PE=polyethylene, etc.

Polypropylene can be ultrasonically welded but most home owners don't have access to the that kind of equipment. Ultrasonic welding is often used to attach grip caps to polypropylene (injection molded) rifle stocks.

If it were me I'd probably buy a new fuel tank, but no doubt they're very expensive.

 

[BAP]

Messick’s has tanks in stock for $1028.58 plus shipping. So if you can find a solution to get yours repaired properly, it would be definitely worth it. Not certain that this link is to the correct one for your tractor.

Kubota #3C131-04140 TANK,FUEL

TANK,FUEL

www.messicks.com

 

[Runs With Scissors]

I have never been able to fix anything made of “plastic”.

As suggested above, I think your best shot/bet is some sort of “mechanical” repair.

Maybe some sort of “Bolt and O-ring” setup?

Way back when, when I was an A&P (technically I still am) we occasionally used a “blind fastener” called Riv-Nuts.

They had a special one that was used for sealing fuel tanks in certain areas

Here is a link, just for “kicks and giggles” of what I am talking about. (there are other manufacturers, of similar products too)

https://www.rivetnutusa.com/rivkle-metric-rivet-nut/rivkle-seal-ring-waterproof-rivet-nut/

Although the tooling would probably be “cost prohibitive”, unless you know someone that is already tooled up.

 

[DONLI]

Is this it? https://www.amazon.com/Marine-Tex-W...B003E1SGD0/142-5998739-0214624#productDetails

Yes that is it!

Don

 

[McMXi]

Messick’s has tanks in stock for $1028.58 plus shipping. So if you can find a solution to get yours repaired properly, it would be definitely worth it.

Yeah, at that price I think I'd try one of the ideas suggested by @North Idaho Wolfman and others since they're not expensive options and might work out just fine. At least if you get the price on a new tank you'll know the worst case scenario.

 

[PoTreeBoy]

If it is polypropylene, you could try welding with a polypropylene rod. Polyethylene is apparently not compatible.

 

[Savoy John]

Long time reader, first time poster here.

Hoping someone has successfully repaired their plastic fuel tank and can share how you did it. I have a 2021 M7060 with a punctured tank that I tried plastic welding using an HDPE welding rod. It seemed ok but started leaking after about 4 uses of the tractor. I re-did it a second time thinking I must not have heated it enough but got the same exact result. Now I am wondering if the tank is not HDPE. I tried calling the dealer to find out but they did not know and Kubota customer service would not tell me because it is 'proprietary information'. The other option I looked into was JB Weld but they specifically state none of their products are rated for contact with fuel. Has anyone had success repairing their plastic tank? If you used a plastic welder, what type of welding rod did you use? Any other success stories out there? A new tank is north of a grand, not including shipping, so I would really like to get the one I have repaired versus replacing it.
Any help or suggestions welcome.

I've brushed "Seal- All" on a metal tank and it worked like a charm, don't see why it wouldn't work on plastic.

 

[BFaronni]

Thanks everyone for the replies...some good suggestions here. I think I am going to try welding with a PP rod as @Savoy John suggested since the rods are cheap and I already have the welder. From what I read, the difficulty is not letting it get too hot to the point where it burns and degrades the weld. I can practice on some old plastic containers first to see how it does. If that does not work, there are plenty of other ideas here. I'll keep everyone posted but it might take a while before I find out what finally works, if anything. Thanks again for the help!

 

[BX'r]

I repaired a hole in a BX tank with this several years ago, no problem.

Amazon.com: FiberFlex Plastic Welding Rod, Flat Ribbon, 30 ft., Black : Tools & Home Improvement

 

[Thunder chicken]

If you are near an airport that has a maintenance shop, see if you can get a product called ' PRC', its a 2 part mix, goop like that they use to seal up leaky 'wet wings', ie. loose rivets that start weeping. It sticks to the wet, jet fuel soaked surfaces.
Something like this:
It has a shelf life so we get the expired stuff all the time, its great for fixing leaky rubber boots, worn work boot toe caps.....

Pro-Seal Fuel Tank Sealant P/S 890 B2 | Aircraft Spruce Canada

Pro-Seal Fuel Tank Sealant P/S 890 B2 This material is designed for fillet sealing of fuel tanks and other aircraft fuselage sealing applications. The cured sealant maintains excellent elastomeric properties after prolonged exposure to both

www.aircraftspruce.ca

 

[GreensvilleJay]

I have seen 'staples' that you heat melt into plastic to 'stitch' piece securely. I'd do that first the 'weld' new material over the area. Also small hole drilled at both ends of crack.

 

[InTheWoods]

Thanks everyone for the replies...some good suggestions here. I think I am going to try welding with a PP rod as @Savoy John suggested since the rods are cheap and I already have the welder. From what I read, the difficulty is not letting it get too hot to the point where it burns and degrades the weld. I can practice on some old plastic containers first to see how it does. If that does not work, there are plenty of other ideas here. I'll keep everyone posted but it might take a while before I find out what finally works, if anything. Thanks again for the help!

Welding is the only way. You will not find an adhesive that properly bonds to Nylon, PP or HDPE.

I've had very good success with plastic welding - the 'game changer' for me is to embed fine stainless steel screen across the crack. It makes a huge difference in the strength of the weld.

I use an old soldering iron with a fat tip, and apply the heat to the screen, pushing it partially into the base material as it melts - then finish with additional filler material, as needed.

I can't emphasize enough how well this works and how much difference the screen makes.

 

[mikester]

google diesel fuel tank liner sealer

I've seen liquid liners used and bladders installed inside the tanks.

You need to get the tank pristine clean and free of any fuel if you want any hope of repairing with epoxies or welding. The shops that used to do this work steam cleaned tanks. Nobody seems to repair anything anymore its often cheaper to replace with new parts.