430 hydrolic oil tank

[mapaduke@yahoo.com]

hi.anyone know a way to get the dents out of the hydrolic oil tank?it still holds oil,just looks like crap.i will be painting the crawler soon and want to do something with it?the gas tank also has a couple in it .

[pop pop]

try squeezing it unless that deforms it more, try pressurizing it, air or,,, try some small explosion,, as when "beading" a tire, point holes away from you,,,, don't try it if you've never done this trick before. try dry ice to shrink dent till straight,or drill a hole in dent, pull it and re-weld hole. grind weld and finish up surface, most times you can't tell it was done. once in a while a torch flamed around dent will relieve it.

[mapaduke@yahoo.com]

thanks for the info.i like the idea of some how preshurizing it but with my luck i will probably bust a seem.this is the small tank infront of the right brake pedle.not verry thick metal.i may try to tack weld screws to it and use vicegrips on the screws to pul out the dent then grind the screws off.i have seen this done in a body shop.

[crancreature]

I can't vouch for it on such a tank, but on large (ie 4") dented copper pipes you can pressurize it, then heat the pipe until its soft and the air pressure pushes the dent out for you neat as can be. I can imagine putting 5 or 10 lbs of air on a tank and using a torch till its starting to get plastic and red, might push it out, be prepared to let off the air pressure quick or you could end up with a bubble instead.
Greg

[KenP]

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[Tigerhaze]

You might see if the dry ice trick works, but I would think the tanks are of a guage that doesn't pop out as easy as an auto body.

I would purge with nitrogen if you envision using a torch in either the hydraulic reservoir or the fuel tank.

If the dents are small, you might consider use of body filler (Bondo); I'm not a big fan of it but trying to pull and hammer out a small dent or drill/cut/torch a dent may cause more problems than what they are worth.

[mapaduke@yahoo.com]

im inpressed with your ideas. im a strong beliver in yankee ingenuity.not sure where to get dry ice?i work for a propane gas co and we use water to purge tanks that we are working on.the water acts as a heat sink and absorbs the heat from welding new collars and footrings on.This may work with the hydrolic tank .Pressurize it with the water still in it?what would i use to plug the inlet and outlet holes. the threads look to be finer than standard pipe?

[JimAnderson]

The hydraulic tanks are rather stout.You can pull small dents from the outside but if your tanks look like most I've seen and the bottom is severely crushed in forget it.My guess is that if you put enough hydro
pressure on the tank to push the dent out the tank will look like a
football.If nothing else works you can split the tank in half just below
the support flange.Beat the dents out from the inside then weld the tank
back together.If you spot weld a strip around one half of the tank it
will hold the seam even and provide a backing during welding.This
works well and the support flange hides the weld seam once the tank
is mounted.JimAnderson

[Ray III]

try dry ice to shrink dent till straight

Now this I got to try sometime, it seems every time you heat sheetmetal with a torch it buckles, being able to do that in reverse would come in handy!

Hydraulic tank should be fine to use a torch on if it's vented. Gas tank on the other hand, be absolutely sure it's dry and all vapor has been blown out!

I have seen diesel fuel tanks welded by filling the tank with fuel first. As long as the weld area is submerged it can't ignite anything. My life insurance policy isn't high enough to try it on gasoline though.

[Tigerhaze]

There's a little more to that dry ice trick- here it is from another website:
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Step 1-Clean dent and area around dent. This in not really needed, but a clean workspace is always best in any situation, and it lets you see what you are working with.

Step 2-Using the hair dryer, heat the dent and an area of about 6 inches around dent. heat until area is good and warm. This causes the metal to start expanding.

Step 3-!!!WITH GLOVES ON!!! dampen your shammy cloth and wrap it in one layer around the dry ice. The shammy is optional, but it helps to keep the dry ice from leaving scratches in your paint.

Step 4-Press dry ice firmly to the dent and hold for about a minute. Then cool the area around the dent by rubbing the dry ice in a circular motion. The cold from the dry ice causes the metal to contract rapidly, and with luck, will shrink the ding or remove it altogether.

Step 5-Repeat from step 2 as needed.
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I have found it only works on small dents (like hail dents) with no crease and even then only part of the time. The trick is the large temperature swings on small dents.

[KenP]

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[mapaduke@yahoo.com]

THANKS FOR ALL THE INFO.
I PRESSUREIZED IT WITH 25 PSI OF AIR AND HEATED THE CREASES WITH A TORCH UNTIL THEY POPPED OUT.THEN I WORKED THEM BACK WITH SOME MORE HEAT AND A BODY HAMMER.NOW A LIGHT COAT OF FILLER AND GOOD AS NEW.