I got the truck all buttoned back up after replacing the head gasket (again) but couldn't get it to start apparently due to lack of fuel. Troubleshooting all the systems let me to determine that the fuel pump apparently quit for whatever reason, and seemingly while the truck wasn't even running because it worked fine right up until I parked it in the garage. But I couldn't get any response out of the pump even when giving it juice directly from the battery.

So I had to drop the tank to get to the pump, and as expected on an '89 4x4, I had to deal with all kinds of rust and corrosion. The top of the tank was a mess, though it was pretty structurally sound. The pump assembly bracket that holds the pump down in the tank was rusted to hell, as was the top of the sender assembly.

I ordered a new pump, bracket assembly, and sender as well as a POR-15 starter kit. Seemed like a good opportunity to try out the POR-15 rust treatment/inhibitor and they sell a starter kit for $20 that was the perfect amount for what I needed to do. After scaling/grinding most of the rust off the top of the tank, I used the degreaser and metal etching products provided in the kit to prep the tank for coating. As with any painting or coating, success is usually determined by the prep and this is no different. I followed the prep with 2 coats of POR-15 applied with a small brush. POR-15 can be topcoated, and topcoating is generally recommended because it is not UV resistant however this will not see the sun so I skipped the topcoat. Pics here are of the tank etched and prepped and then coated.








The tank mounts up alongside the frame, which leads to dirt and debris getting trapped up there and holding moisture. This of course leads to rust and rotting of the frame. I was aware of this problem so I took a close look at the frame and at first it looked fine. Some aggressive poking and prodding revealed that the metal had indeed thinned in spots and required being cut out and replaced with some patches of steel. Following are the pics of my progress as I cut out sections, fit patches of 1/8" steel in, and welded everything up. I'm obviously no pro welder, and the process was made more difficult by the fact that I was having to contort myself underneath the truck at weird angles to do the welding in a tight spot. I think it will do the trick though, and the welds will be ground down and the whole section coated with POR-15 to help resist further rot.







Questions and comments are welcome

Next up is grinding down the welds, coating the frame, then reinstalling the tank and seeing if all this work will actually get the truck running again...

If you can coat the inside of the frame you'll be money ahead, but that is a tall order.

Yeah, been thinking about that as well... maybe the old used motor oil trick or something.

The frame is actually painted inside and out from factory. The oil trick is what I am planning on doing.

Nice job; nice writeup. Thanks for posting the frame pix tho'. Something we need to be aware of on these older jalopies. First tank I've seen POR'd from the outside.

Give your wire harnesses a good inspection while everything's out of the way. <img src="/forums/images/graemlins/kewl.gif" alt="" />

Thanks. The inside of the tank pretty much looked brand new, no rust that I could see. I ground down the welds on the frame, and removed as much rust as I could from the rear mounting bracket then degreased and etched both. I should be putting the POR on them tonight, and hopefully gettting it all mounted back up Fri or Sat.

You have done a lot of work and it is looking good. However, you should have used one piece of plate and covered the whole area. You should also not grind down those welds, just clean up the area and coat over them. By grinding, those down you comprise the integrity of the weld.

Here is a picture of how it should be plated, the yellow dots are holes drilled in the plate so they can de rosette welded. I use ¢-inch holes randomly placed on the plate. I would use ?-inch plate.




Here is a picture of what I am talking about, this is the front section of my frame that had 5-6 cracks in it.

I agree, I would like to have used one solid piece. At the time though all I could get my hands on was 3"x36" stock so I had to patch it together.

Also, I understand what you're saying about the rosette welds but that metal was so thin it would just blow right through it. Maybe my technique just isn't good enough, in fact, I know it isn't but I'm getting there.

Your welds look awesome <img src="/forums/images/graemlins/kewl.gif" alt="" />

You must be left handed, David?
Agreed, nice work.

Not to step on anyones toes, but frame repairs are best if the patch panels don't have straight edges. Fish plates are best. You should also be carefull about welding perpendicular to the frame rails.