# Fix Case 4210 fuel tank leak around plug?



## SVanDee (Oct 15, 2010)

My Case 4210 has left and right plastic fuel tanks slung under the cab. There's a 1" flat plastic plug about in the middle of the rear end of the right tank (the tank with the filler neck). Diesel fuel is seeping out from around the plug. It's not a very bad leak but it's a nuisance remembering to put a pan under it and I worry that the plug will come out altogether some time probably while the tank is full. A new tank is around $600 so I'm wondering if it's possible to fix this one?

The plug may be filling a hole for some attachment that isn't used in this model of the tractor. It doesn't look like it is intended to be removed. The parts catalog on Case's web site just shows a "tank assembly" with no subcomponents. The tank plastic around the plug is bunched up like maybe the plug was heat-welded into place. There are no flat sides on the plug for a wrench or slots for a screwdriver. I might be able to pry it out but the tank material may be too thin and irregular to hold a replacement, screw-in plug.

Would you care to suggest how to replace the plug or what glue would work to hold a patch over it?


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## cyrush (Apr 20, 2010)

I beleive what you are looking at is amoulding mark in the plastic not a separate plug ?? it has obviously cracked around the moulding. Has the practor been operated over rough ground where the bottom of the tank may have been in ground contact ?? For forestry use tank guards are usually fitted .

To repair the tank will need removing, washing out to remove all oily residues then acompany specialising in plastic welding should be able to repair it for you.


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## SVanDee (Oct 15, 2010)

I don't think the tank has been beat up. The tractor only operates over smooth turf in an orchard and lives in an enclosed building when it's not working. It's 16 years old but with only 2122 engine hours. Anyhow, thanks for the suggestion. I didn't know there were companies that did plastic welding.


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## cyrush (Apr 20, 2010)

Do a google search for "Plastic Welding" and learn more about it??

You can buy kits to do it yourself??, your biggest problem is getting the oily residues out of the crack area before welding it , wsahing it finaly with acetone or other fast evaporating solvent will probably do the job.!!


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## SVanDee (Oct 15, 2010)

Read about plastic welding on the web. Sounds like a useful thing to know how to do.

However, I'm trying some Bondo with fiberglass in the resin on the gas tank first. I've used it to repair a tractor grill and Kohler small engine cover before and been surprised that the vibration doesn't seem to bother it at all. Don't know whether it will take the gas tank flexing but I could apply it quickly without removing the tank. If it cracks or comes loose, I expect I can sand it off and try plastic welding. 

I won't be doing much with the tractor now during the dormant season. Will try to remember to add a comment here about whether it worked next season.


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## jhngardner367 (Apr 5, 2011)

The Bondo won't hold, since fuel ( Gas or Diesel) will destroy the resins that bond it.
Many auto body repair shops/motorcycle /boat repair shops have the plastic repair systems,and it's reasonably priced,to have them do it.Just drain it,and flush it,before taking it to them.
Some use heated air,while others,(such as mine) use a type of soldering iron with a special foot. After a bit of practice,it works well !


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## cyrush (Apr 20, 2010)

Have severe doubts that will work,and it will make a later repair by plastic welding more difficult???


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## byronlj (Apr 19, 2011)

Auto parts stores sell gas tank repair kits. Petroleum products don't bother this epoxy type putty. It also sticks to plastic gas tanks so it should work for your situation.
Dave


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## cyrush (Apr 20, 2010)

The biggest issue will be getting the repair area clean of fuel and oily residues (as for plastic welding) so that any patch material will adhere!!

A good plan is to clean the area with something like acetone and spray it into the crack to flush out oily residues, then let it air dry or use airline to blow dry.( after draining the tank of course!!).


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## mrsherlock (Dec 13, 2012)

Go to Eastwood.com and look at their Gas Tank Sealing Kit (PRO II) #10165/6Z. I am not familure with your issue you may want to call them for clarification. I use it on my International B414 gas tank ( steering colum goes through the middle of the thak) and the weld seam cracked. This product fixed the leak and a friend of mine had two Fordson tractors with rusted out tanks and a 51 and 49 chev gas tank that it sealed up. saved buying a new tank. There is very good instructions on cleaning out the tank which would work even if you were to plastic weld the leak. best of luck. I agree wtih above do not try bondo


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## SVanDee (Oct 15, 2010)

For better or worse, I had already applied Bondo to the tank before the posts that said it wouldn't be durable. I did rough the plastic up with a Dremel wire-wheel and clean it good with Acetone. The Bondo seems to be adhering well. Guess I won't try to re-work it now but I'm saving all your suggestions so I can fix it better when it starts leaking again. Thanks a lot for your help.


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