fuel tank welding MEP002a

[hedgehog69]

Looks like I need to get the tig welder out and weld some pin holes on the bottom of the tank. Tank had a lot of rust in it...flakes...and some water. I reached what I could with a rag and got some of it out. Then I took it to car wash and hit it with high pressure soap and water. It doesn't look like there has been any fuel in the tank for quite some time, so fumes aren't a concern.

I am thinking the process will be to drill the pin hole to remove all or as much rusted material as possible....and then weld the hole closed.

Open to suggestions!! Anyone else had to do this?

Rest of the tank appears to be in good, useable condition, so I am hoping I can use this one and not buy another one.

 

[treeguy]

If its bad enough, I would toy with the idea of cutting out the bad spot large enough and make a plate to bolt in with a gasket so it would make cleaning out easier in the future.

 

[rosco]

That tank is zinc or tin coated. If you weld it, it will burn the finish back even more, not to mention warping/distorting it. Best bet, and simplest is to solder the pin hole shut. A copper solder iron will do wonders. Clean around the pin holes with scratch cloth & use acid core solder. The solder iron has no flame, so it is safe around fuel.

 

[PeterD]

I agree with Rosco, I'd solder it, either with an iron or a torch. (I'm good with a torch so that's usually what I use for big jobs, but a big iron would work.) To solder you need to get the area completely clean, and have NO rust/corrosion present, just bright shiny steel or whatever it is coated with. Us a strong acid flux (with care) and make sure you clean it inside and out very well when done.

I've done a number of tanks that way with (generally) good results. Only one problem case, a motor bike tank with about 40 holes in it that was a PITA to do--it kept overheating and the patches next to where I was working would sometimes come loose! (Dang, that was a lot of holes to fix!)

 

[kipman]

After it is fixed, why not get it lined?

 

[steelypip]

One standard motorcycle-sized can of redkote fuel tank sealer should coat the whole tank easily and will solve the problem. Plug any holes large enough that you can see through them (solder is good) and then put the redkote down to get the fuel away from the metal.

Yes, kreem also works fine, but I and my old motorcycle friends have generally had better luck with redkote, particularly with fuels with aggressive solvent properties.

I have to say that I was really happy when I washed out the tank on my MEP-002A and decided that it must have tinplate, galvanizing, or a thick layer of terne plate on it - it had sat with water in the bottom for most of a year and there was no detectable damage. The mil spec tanks are definitely stouter than motorcycle tanks...

 

[hedgehog69]

After it is fixed, why not get it lined?

Line it?? Is there some kind of chemical process that does a great job of cleaning the inside? My hand will barely fit into the hole,,,and then I have very limited movement to clean it.

Or....is ther a company that does it? But again...if it starts running into bigger $$, it would be cheaper to just find another tank

 

[hedgehog69]

That tank is zinc or tin coated. If you weld it, it will burn the finish back even more, not to mention warping/distorting it. Best bet, and simplest is to solder the pin hole shut. A copper solder iron will do wonders. Clean around the pin holes with scratch cloth & use acid core solder. The solder iron has no flame, so it is safe around fuel.

Thanks..!! That never crossed my mind.

 

[kipman]

MEP tanks are hard to find and pricey, if you can find one under 150.00, that is a very good price, the liner I am thinking of is poured in.

 

[kipman]

Also look at the POR brand of products, they are very good.

 

[PeterD]

Eastwood has several kits for coating fuel tanks, and I've found their products to be excellent.

 

[hotdogs151a2]

I recently bought a 10KW. It ran and produced power well. The fuel tank leaked at the seam, so being a welder I built a new tank using the existing ports (thread-o-lets) and welded them to the tank. The replacement tank fit and worked well. You can control your heat with the TIG RIG to reduce warping.
Good luck however you decide.

 

[hedgehog69]

I'm going to try an electric soldering iron...will see how I get along. If that fails, I'll get some 16ga steel and build a new one. Won't look 'authenic', but it will fit well and work. thanks all !

 

[mightymanx]

I use Muratic acid 50/ 50 water to clean the tank it will remove the rust and any residual petrol products.

it is available at any hardware store for abotu 15 bucks a gallon

mix follow the directions but make it 50 50 ish
pour
cap
slosh
sit an hour or so
slosh
dump
rinse
check
repeat if needed
dry
weld
seal Redkote or POR15 tank sealer
use

 

[hotdogs151a2]

Mr. Hedgehog69:
I used 18ga galvanized steel for ease of fabrication on mine. When I got it painted with CARC paint it looked not bad.
Thank you sir, Hotdog

 

[Gunnermac]

After having restored a number of cars and trucks (40's ,50's, and 60's) I have found they all have some rust inside the tanks if they have been sitting for any length of time time. Soldering along with coating is the way to go. There are a number of quality coating available, this is not the place to try to save money. Cheap coatings will cause you more grief than you can believe. They peel off and get into the fuel system with results that you can imagine. The ones we have used come with an etching solution that will clean out rust and gunk. After you etch the tank examine it very closly as the crap inside may conceal pin holes that you have not seen before.

 

[glcaines]

A lot of radiator shops will clean out the tank for you and solder up any holes. Once it is clean and tight, coating the inside is easy.

 

[Keith_J]

I had the same problem. To clean the tank out, remove the 6 rivets on the fuel tank's cap boss/cage. Then desolder and knock the rivets in. Once the cage is pulled, the interior is easily accessed for scraping and cleaning. I used phosphoric acid to dissolve the rust, then drilled out the pinholes to solid metal, using ER 70-S6 wire to weld as it has more deoxidizers than S2. It took several tries as I was water testing and each time additional corrosion from water caused new holes to form.

Once clean and welded, I tinned the solder flanges and brushed off excess solder. Then riveted and soldered, taking care to seal each rivet.


I used the POR US Standard Fuel Tank sealant, plugging the 1/2" NPT bosses with hot melt glue. Should have used 1-1/2" and 1-1/4" plastic plugs on the gauge and switch bosses so those had to be chased.

Also sealed the weld area with POR-15 on the outside.

 

[dogkiller]

a good heat gun works great for soldering fuel tanks ect...
able to heat a larger area with no flame....