They can be welded. Cleaned then submerged in a tank with an inert gas pumped into the open part
Tanks can be coated too. A viscous liquid is put in then the tank is put on a rotating rack to let the sealer coat the inside
On a clam truck I owned the step saddle tank rusted where the drivers toe kicked the tank. Years of abrasion and road salt rusted the metal away. I called around to get prices for a used tank and welding. Fair prices but I gave it the Tom Touch first
Kept the fuel level in the bottom third of the tank
Used a wire brush head in my angle grinder to clean off rust and scale
Cut a sheet of aluminum for the patch
Used my hand punch to make holes around the edge of the aluminum
Laid the aluminum on the tank and used a felt tipped marker to locate the rivet holes in the tank
As I drilled the holes in the tank a helper kept the nozzle of the shop vac next to the drill bit
Clean all mating surfaces with degreaser like brake cleaner
Get sealed pop rivets
Mix up a big gob of two part epoxy get the stuff with slow setup
Slather the backside of the patch and slap it in place
Use 3-4 needle nose scribes to locate the patch on the tank
Start popping rivets in the center holes of each side
Keep popping in rotation to flatten the patch...work towards the corners
Smear any epoxy squeeze out over the edges and then the tops of the rivets
Have a as a reward while the epoxy sets up. Maybe let the epoxy setup overnight
Mix up another gob if epoxy. Use quick set now
Rough up the surface of the epoxy
Slather on a thin layer covering the poprivets and edge of the patch
I’ve patched several tanks doing something like this over the years. All patches held. No cracks or leaks
If you don’t need a sheet patch there’s another variation
Same procedure...start at the drill and vac step
Swiss cheese the area to patch
Use quick set epoxy
Mix and wait just a bit. You want the epoxy to be like thick peanut butter
Spatula the epoxy on and force some through the Swiss cheese holes. The epoxy will mushroom on the other side and acts like a washer and nut or pop rivet
Smooth out the epoxy
Let it set up
Mix another batch and spread it on. Let the second layer cover the first and out a bit more. Ever done any sheet rock taping and kidding? Same idea
Did this on plastic gas tanks for blower and chainsaw. Wore out the machines and no leaks.
Hey thanks for all that info I actually don’t have enough time to read it all right now I’m out the door to work. I will drop in later. But I did not know they could be coated, that’s what was wrong with mine too rusty inside and clogging the fuel pump
Tom I can’t thank you enough for that step by step process just got a chance to read it all. Actually only half of it so far it’s a lot to take in! Considering all that detail with restoring it $800 for a new one doesn’t sound so bad now. But I was thinking and maybe I could use an old air compressor tank.
I was looking for a larger gas tank for a Toyota pickup camper that I have. It didn't take much Google time to find out that others have gone down that path.What I found was that a tank from a particular year Ford pickup bolted in nicely with more capacity.
What else I found was a whole after market for gas tanks. All sorts of sizes and configurations. Plastic tanks don't rust..hint hint
There is also a huge marine market. Just replaced mine a year or two ago. Found an aluminum one at the scrap yard. Took it to a welder to refit a return line into it. All in all in it for less than $100 and it’s a few gallons bigger.
My Ram has a 25 and a 50 gallon plastic tank. For cost and simplicity plastic may be one of the first things to look at when replacing a tank.
I was in a muscle car auto shop last year and was surprised to see a bunch of beautiful custom aluminum radiators hanging up for about $300 each. That will be the first thing I check into if I ever get a $900 or some such quote to replace a chipper radiator too.
The radiator on one of my chippers started to leak so I pulled it and took it to an old-line radiator shop. The guy wasn't busy so he tossed it on the rack and dipped it into the tank for testing. He found that LOT of leaks in the tubes. He told me that the sawdust fines get packed in then they get wet of course. That makes for a corrosive solution that erodes the fins over time.
His solution was to recore it using my top and bottom tanks. The core was made with fewer tubes, spaced a little further apart and the fins were almost three times further apart.
He told me that there was just as much cooling capacity. He'd done enough chippers over the years it was old hat to him
The radiator guy said that this core material was made for dusty conditions.
I had a PM program to blow out the radiator in March just as the season was beginning. THen about every 6 weeks through the season until November. LIttle chipping in the winter.