Fuel Tank Leak

[rwork]

Discovered I had a leak in my R3039H fuel tank today. Found a large puddle of fuel on the barn floor. After a closer inspection, it appears to be a tiny crack at about midway on the front side of the tank.
There is an indent which has a retainer bar across the front of the tank, located behind the seat, which is the location of the leak. I grabbed some plastic tank repair putty from the auto parts store, and tried that as a temporary fix, until I can recheck it mid-week. I have my doubts about it working.
Can't imagine what would cause it to just suddenly begin to leak. I've read of some people using a soldering iron to repair plastic tank leaks, put I guess I need to pull the tank so that I can see exactly what's going on. Even thought of trying some 5200 sealant.

Anyone have any experience with repairing plastic tank leaks?

 

[farmer2009]

I've repaired plastic tanks but never for fuel. They were always sprayer tanks.

I always used an epoxy tank repair kit and it would last for 12-18 months but always ended up replacing the tanks. Most leaks were in seams and molding corners. So hard to get a good repair.

 

[Tractor Seabee]

Plastic tanks can be welded. There is a hot air torch method as well as using a hot iron method. As in welding metals you have to melt and fuse the tank and the repair rod. It is more of a stirring process. Careful, too much heat and a blob will fall out same as welding steel. If you can O/A weld steel you should be able to master the air torch after a little practice. Works best in the flat position although, I have done it in other positions, even overhead. Harbor Freight has both types. Link: Search results for: 'plastic welding'

Ron

 

[bruceatlam]

Read through this thread:

http://www.tractorbynet.com/forums/...g/269040-r3039-fuel-tank-leak.html?highlight=

My latest update is that the new tank that my dealer had forwarded to me also developed a leak at that same seam/mold separation line. It wasn't in exactly the same location on that seam but it was on the same seam. I believe that I had a bad fuel cap. It wasn't letting air enter as the tractor used fuel --- as a result the tank started to form a vacuum and flexed that plastic tank wall which resulted in the crack at the seam. I eventually figured that out and bought a new cap which solved my problem. My epoxy seam repairs have held without issue. So far anyway -------------

 

[rwork]

Bruce, thanks for the reply. After looking at your pics, i believe that's the same spot mine's leaking. I've had my tractor a little over three years, so I'll likely try to repair it myself. Might try some 3M 5200 sealant.

 

[bruceatlam]

Same here --- a little over three years, if I remember correctly, you bought a couple of months after I bought mine. I'm just past a year on my epoxy seam repair. I check my fuel cap most every time that I use the tractor. I don't want any more fuel tank vacuums on a plastic tank.

 

[PILOON]

A soldering iron can be used to melt and fuse most plastics.At times I also have used hot glue guns to add more 'plastic' to the repair site.

Another product that I have had success with is windshield cement (in a tube) that they use when replacing car window.
Basically it is polyurathane caulk very similar to some brands of caulking sold at building supply houses.
One brand I often have used is FLEXTRA.

I even once patched a hole in a battery that I had dropped and otherwise would have been scrap.

As a test we once stuck 2 pieces of clean metal with that caulk (and plastic to plastic) and tried to pry apart. Virtually impossible!
Couple of weeks ago we patched up a rusty leaky old tractor fuel tank using the caulking technique and so far so good.

What sold me on the idea of that caulk was the lumber supply had a 'point of sale' device that consisted of a block of metal with sample color cords of the caulking that literally hung down from the block. Naturally folks would grab the 'cord' and pull.
Well I pulled that 10" cord and stretched it maybe 20" and it never let go.
If 1/4" glued to a block of metal had that kind of adhesion I knew that I found many new uses for it.

 

[bruceatlam]

FWIW, I've never had any luck "welding" plastic. Tried three or four times. The weld seam always seems to turn out brittle and then, as a result, cracks easily. I'll readily admit that I may not know what I'm doing, but for the time being, I'll pass on welding plastic.

 

[Threepoint]

Rwork, if your fuel tank is HDPE, which I suspect, it is a chemical cousin to paraffin wax. Sealers and adhesives just won't stick to it. :mur: In your case it sounds like the crack was caused by continual flexing of the plastic, and that's going to continue to some extent whenever you use the tractor, even if you resolve a venting problem. You only have access to the outside surface, so you can't sandwich the crack mechanically. If you just try to "weld" over it with heat, you'll want to remove the tank anyway. My advice is to just bite the bullet, order a new tank, and don't look back!

 

[rwork]

I'm going to give it a try to stop the leak. Price of replacement tank is $300 ! Ouch

 

[Maxify55]

Had to replace my tank after only 100 hrs on the clock.
My dealer covered it under warranty.
I figure it's a design flaw. I happened to mention it while it was in the shop for something unrelated.

Turns out that there's another design flaw with the auto-pilot/cruise control module.
Seems there's a wire from it to the ignition that is danger close to the exhaust.
Which melts the coax and shorts a 10 amp fuse.

 

[silverstreek]

At $300.00 for a replacement plastic tank, I believe check into companies who build custom aluminum fuel tanks for boats would charge to build a tank to your measurements?
Just a thought?

 

[hockeylover86]

That tank would be blow molded HDPE, so it will be tough getting something to patch it.

 

[Gary Fowler]

I had a leak on my tank within a few months. The tank was poorly designed with 4 cast in nuts to hold a deflection plate to the bottom of the tank. Anything hitting the plate would flex the nuts and in turn crack the tank. Dealer warranted the tank but it took over 6 weeks to get a new tank. In the meantime, I removed the tank, cleaned the 4 bolt spots with acetone and put some grooves in the linear cracks then used a brush on my 4" grinder to rough up the area well. Next I cleaned it well again with acetone and applied a generous coating of JBWELD epoxy. I still have the "new" tank in the box as the epoxy fix is still holding 5 years now and counting.
It isn't in a flexing situation so it may not be the best for your spot since it dries hard and inflexible.

 

[rwork]

I sent an email to LS about a week ago, just to see what they would say about my tank. I actually got a phone call this afternoon, saying they would send me a new tank. I'm out of warranty, so they will send the tank, and I can install myself, or work something out with my dealer. I think I can handle that!!:thumbsup:

 

[bruceatlam]

So, did they offer up a reason "why"???

And yes, easy to change out the tank. Takes about an hour first time ---- 1/2 hour thereafter.

 

[MinnesotaEric]

Anyone have any experience with repairing plastic tank leaks?

I had a different kind of repair but the goop I used works good.

 

[rwork]

So, did they offer up a reason "why"???

He said sometimes the retaining bar is tighted too much. I think there is too sharp of an angle molded in, causing the weak area.

 

[lostcreekranch]

I had a small fuel leak on my XR4046HC at about 30 hours. It was a small crack at the point where fuel hose connects to bottom of the tank. RCO replaced tank without question. No problems since then with about 145 hours.

Sent from my iPad using TractorByNet

 

[SPYDERLK]

I had a leak on my tank within a few months. The tank was poorly designed with 4 cast in nuts to hold a deflection plate to the bottom of the tank. Anything hitting the plate would flex the nuts and in turn crack the tank. Dealer warranted the tank but it took over 6 weeks to get a new tank. In the meantime, I removed the tank, cleaned the 4 bolt spots with acetone and put some grooves in the linear cracks then used a brush on my 4" grinder to rough up the area well. Next I cleaned it well again with acetone and applied a generous coating of JBWELD epoxy. I still have the "new" tank in the box as the epoxy fix is still holding 5 years now and counting.
It isn't in a flexing situation so it may not be the best for your spot since it dries hard and inflexible.

Some of the epoxies adhere very well to plastics. ... The "Double Bubble" listed as vibration resistant in the link does well. It is semiflexible instead of dead hard like many.

McMaster-Carr