Patched small leak in gas tank of my '92 Exceed (gas engine - 4G64, not diesel).
No photos, sorry, but I think not necessary for this repair.
Around Christmastime I started smelling gas when near the van (outside). I found gummy residue on the bottom of the steel shield plate under the rear gas tank. Gas was seeping out somehow. Here's how I fixed it, after running the van long enough to use up most of the gas that was in the tank.
1. Remove the steel shield that warps around the bottom of that tank (3 bolts). I thought I might have to hold the tank in place, but not necessary. Clean that plate while it is off the van.
2. Clean the gummy residue off the bottom of the gas tank. I used spray on de-greaser and a rag. I could then see where gas was seeping out of a small spot on the front lower edge. No idea what caused it. Once I cleaned it, the leak got bigger, I assume the pinhole leak was gummed up, and I cleaned out the gunk so the gas flow increased.
3. Drained the remaining gas from the tank.
4. Cleaned and sanded around the hole down to bare metal, using sandpaper. Cleaned the bare metal with lacquer thinner on a rag.
5. I used JBWeld Steel Stick, an adhesive epoxy putty, to fill the hole. I put on a pancake of SS about 1.5" diameter and about 1/8" thick. I pressed it in place as hard as I could with my hand. At first it didn't want to stick, but after holding it in place (with a piece of wax paper on my hand) for a minute or two it stuck. I held it in place for several minutes.
6. Let the epoxy set for a few hours. It seems like it bonded well to the tank.
7. Around the edges of the "pancake" I then smeared some sticky gasket material I had on hand. My theory is this will prevent water (ice) from getting into the joint where the putty meets the metal, in case that might weaken the bond.
8. I was going to use black spray paint to protect the rest of the bare metal where I had sanded off the paint. But the weather was cool, so I just smeared more of the gasket material on those small spots of bare metal.
9. Replace the metal outer shield.
10. I put about 2 gallons of gas in the tank and tried to start the car. No luck. Cranked and cranked on the starter. No luck. Waited an hour (in case it was flooded?) then cranked. I guess that draining the tank somehow disrupted the flow into the fuel pump. I added another 1-2 gallons at which point the car stared up. I think it took about 3-5 gallons to get to the point where it started.
This was about 1 week ago. No sign of leaking yet, so I hope that's done. If not, I think I will just screw a small sheet-metal screw into the leak hole, with some gasket goop or more Steel Stick between the screw head and the tank.
