Replacing all fuel lines, 88 RCSB TBI 4.3L

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kennythewelder

Officially Retired, B31-3 (6-G) certified welder.
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Welding 101. Clean the base metal, before you ever strike an arc. Clean doesn't mean wipe it off with a rag ether. You need to get down to clean, shiny metal before you do anything else. Then you can fit in the patch, then weld after grinding off any slag, or scale. Your weld is just a bunch of spot welds. I'm not downing you, just letting you know the correct way to do the job. I would have buffed the whole part clean first. The removed the rotten metal, then ground to shiny metal, then make the patch, then weld it un place. Then prime and paint. That way, I know the repair will be there for a very long time. As for the gas tank, I don't like to weld on them, but it can be done if you perp it rite, and back fill it with a non flammable substance. When I was a kid, we had a neighbor kill himself by cutting into a 55 gallon drum with a torch. All in an attempted to make some BBQ pits to sale. I will never forget that. Most of the time, I repair gas tank holes with 2 part expoxt putty.
 

DeCaff2007

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Welding 101. Clean the base metal, before you ever strike an arc. Clean doesn't mean wipe it off with a rag ether. You need to get down to clean, shiny metal before you do anything else. Then you can fit in the patch, then weld after grinding off any slag, or scale. Your weld is just a bunch of spot welds. I'm not downing you, just letting you know the correct way to do the job. I would have buffed the whole part clean first. The removed the rotten metal, then ground to shiny metal, then make the patch, then weld it un place. Then prime and paint. That way, I know the repair will be there for a very long time. As for the gas tank, I don't like to weld on them, but it can be done if you perp it rite, and back fill it with a non flammable substance. When I was a kid, we had a neighbor kill himself by cutting into a 55 gallon drum with a torch. All in an attempted to make some BBQ pits to sale. I will never forget that. Most of the time, I repair gas tank holes with 2 part expoxt putty.

I appreciate the advice, however, if I gave two EFF's about this truck anymore, I'd have sandblasted that entire part and done that weld a lot nicer.

Why? Wrench on random junk all weekend, seemingly making zero progress... only to see others driving beautiful, less-than-a-decade-old trucks. Yeah, it kinda kills the mojo after so long.

Please don't take this lackadaisical reply personally. It's got nothing to do with you, nor anyone else on GMT400. It's just me not giving much of a damn about cars anymore.
 

DeCaff2007

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Well, I might as well post an update. Finally got all the fuel lines plumbed. From pump to TBI, and pump to charcoal canister, everything is brand new.

I found a serviceable fuel filler neck at the yard from a 94 RCLB.The whole truck was rotted out, yet the filler neck managed to survive with only surface rust. Many of the 400's we see in the junkyards up here in the rust belt were used exclusively for towing and plowing. That means rust and rot, so I definitely got lucky with that find.

I also had to go to three different parts stores to find the correct steel nuts and union fittings. It's pretty sad when the employees behind the counter give you a deer in the headlights look if you aren't speaking spanish.

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So then as you all can see, my tank repair is holding. I might just take the $$ saved there and replace the leaf springs, shackles, and hangers. They are all pretty well shot.

Aside from that, I crossed my fingers and turned the key. It started, but fuel was pouring from all along the frame under the cab. :mad: Now what?

It turns out I had left one single fitting loose. Gave it a few turns to tighten it down and voila, no more leaks. Damn thing still takes a few cranks to start (it always has), but at least now I can be sure it's getting fuel.

Next up, I need to patch up the driver side frame where the leaf spring shackle and rear bumper are. Seems to have a few areas of rot. Just swapped out the cylinder for my mig welder this morning, so let's see how big of a mess I can make lol.
 
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