B7100 fuel tank leaking

[Sylvester]

Hate fuel leaks, found my tank has a 25mm ( 1 inch ) split in the recess where the tank strap secures the tank, its near the bottom of the tank, due to this covid 19 virus, had no option but to get a new tank at great cost rather than see if anyone can repair. Has anyone repaired these plastic tanks for a spare or any advice on preventing it happening again, considered either covering the straps in rubber tubing or heat shrink. Its only got 800 genuine hrs on the clock at 30 years old, it was still nice and yellow and still the original shape.

 

[Dave_eng]

Any plastic from 30 years ago when it was manufactured has done a great service in my opinion to have lasted this long.

Environmental factors, where the tractor is stored, temperature changes it experiences and sunlight are all powerful forces working against even modern plastics. Think of the cars from the 70's, 80's and 90's who experienced cracking of the plastic surfaces on the dashboards. Such failures do not happen today with more modern plastics.

Your new fuel tank is undoubtedly made from better plastics today than the original one.

Do not worry about having a spare.

I spent a lot of time and $ buying plastic welding equipment and welding an ATV fender. Yes I could weld the crack but all the plastizers in the fender had long since evaporated and the fender just cracked again nearby.

Dave

 

[Pau7220]

considered either covering the straps in rubber tubing or heat shrink

I definitely would. I have a large leftover piece of epdm rubber roof I use all the time for protecting parts in situations like this. 3M super weatherstrip adhesive locks it in place very well.

 

[SidecarFlip]

Had that years ago on one I owned as well and even then the tank replacement was a wad. I'd cut some innertube and put it under the straps.

 

[Sylvester]

Its been kept under cover all its life, I hope its better plastic on the new one, part no ended 003 so its had 3 revisions. I'll put some inner tube on and try to make sure the strap is centred and hope for another 30 years! I think the engine vibration has a lot to do with it, not the smoothest running engines.

 

[Dave_eng]

Its been kept under cover all its life, I hope its better plastic on the new one, part no ended 003 so its had 3 revisions. I'll put some inner tube on and try to make sure the strap is centred and hope for another 30 years! I think the engine vibration has a lot to do with it, not the smoothest running engines.

Something for you to consider with the use of inner tubes to add cushioning to prevent tank failure in the future.

Rubber tubes are manufactured using plasticizers as are most plastics such as your new fuel tank.

Fastening a rubber component known to contain high amounts of plasticizer against another product made with plasticizers may accelerate rather than retard a future failure.

Plasticizers are known to leach out of products and you will be creating a situation where these tube plasticizers will be in intimate contact with the plastic fuel tank.

If you decide that the cushioning you want is necessary, my suggestion would be to add a layer of 6 mil poly between the tank and the rubber tubing. The goal to provide a barrier between the tube and tank.

Dave

 

[rfoxinc]

I just replaced my tank with the same issue.
Found one in Ohio [NOS] for $150 which was <1/2 what the Kubota dealer wanted.

They were showing 1 more on hand, I can get the # if you are interested.
I cut sections from a clear rubber floor mat as an extra insulator.

Good Luck,
Bob

B7100 HST