Everywhere I looked online said that you couldn't cut a hole in the floorboard of your SWB Trailblazer to change the fuel pump. Challenge accepted!
You're going to need a couple air tools:
- pneumatic nibbler
- pneumatic hammer
First, you'll need access to the floorboard. You need to remove the rear driver's side seat. It's just two nuts. Move the seat forward, take off the two bolts, and pull out the seat. Then you remove the trim from the bottom of the rear driver's side door jamb and the B pillar trim. Move the front driver's seat up all the way to give yourself a little more room. Move the carpet by making a couple inconspicuous cuts. Be careful of the wire loom that runs right over the fuel pump.
I drilled a 3/4" hole where I knew the pump was so I could figure out exactly where I needed to cut. The fuel pump is right between the two studs that hold the the seat down. Once you figure out where it is, use the nibbler to cut as big a hole as you can over the fuel pump. I used a socket to hold the wire loom up out of the way. There is a weld front-ward that will be your northern boundary. The raised area where the seat mounts will be the western, eastern, and southern boundaries. Rotate the head of the nibbler if you need to. Once you have a rectangle-ish shape cut out, you'll likely see this:
Pull relay 41 under the hood and crank the engine to depressurize your fuel system. Curse, swear, and eventually remove the fuel lines from the fuel pump "simply" pinching the clip and pulling the hose off. Rust gets stuck between the clip and the line, so I ended up wiggling them until the lines broke off; that made removing the lines from the fittings a bit easier. My AC Delco fuel pump didn't come with the plastic clips, so save your old ones. Use that pneumatic hammer we talked about earlier, and knock the retaining ring off. I think this job would have been impossible without it because of the space constraints. The specialized tool to take off the ring may have worked, but I cut a hole in the floorboard of my TB. You think I buy specialized tools??? NOTE: Before and after removing the ring, I vacuumed off all of the rust and crescent-shaped pieces of metal. Using the hammer will knock a lot of rust off. You don't want that in your tank.
I was a bit worried about being able to pull the pump out of the tank, but with the ring removed, the pump pulled out easily.
Pretty clean!
Install your new pump and lock ring. I wouldn't reuse that old, rusty ring. Again, the pneumatic hammer was a necessity. Reconnect the fuel lines and electrical connector. Start your truck to see if gasoline is spewing out like before. It's not. Success!
Paint the edges of the floorboard that you cut so it doesn't rust, then use a nibbler to cut some sheet metal of similar thickness to a little bigger than the hole. Paint it, don't wait for it to dry completely (because who doesn't like paint covered fingers?), put a bead of RTV around the hole, and pop a few rivets in. Self-tappers would work as well, but just make sure they're short.
Replace the padding and carpet. I used some sticky tape to stick the carpet together where I cut. Reinstall the trim pieces and rear seat, and you're done!
Thumb your nose at the internet who said it couldn't be done.
Let the "you're gunna die" comments begin.
You're going to need a couple air tools:
- pneumatic nibbler
- pneumatic hammer
First, you'll need access to the floorboard. You need to remove the rear driver's side seat. It's just two nuts. Move the seat forward, take off the two bolts, and pull out the seat. Then you remove the trim from the bottom of the rear driver's side door jamb and the B pillar trim. Move the front driver's seat up all the way to give yourself a little more room. Move the carpet by making a couple inconspicuous cuts. Be careful of the wire loom that runs right over the fuel pump.
I drilled a 3/4" hole where I knew the pump was so I could figure out exactly where I needed to cut. The fuel pump is right between the two studs that hold the the seat down. Once you figure out where it is, use the nibbler to cut as big a hole as you can over the fuel pump. I used a socket to hold the wire loom up out of the way. There is a weld front-ward that will be your northern boundary. The raised area where the seat mounts will be the western, eastern, and southern boundaries. Rotate the head of the nibbler if you need to. Once you have a rectangle-ish shape cut out, you'll likely see this:
Pull relay 41 under the hood and crank the engine to depressurize your fuel system. Curse, swear, and eventually remove the fuel lines from the fuel pump "simply" pinching the clip and pulling the hose off. Rust gets stuck between the clip and the line, so I ended up wiggling them until the lines broke off; that made removing the lines from the fittings a bit easier. My AC Delco fuel pump didn't come with the plastic clips, so save your old ones. Use that pneumatic hammer we talked about earlier, and knock the retaining ring off. I think this job would have been impossible without it because of the space constraints. The specialized tool to take off the ring may have worked, but I cut a hole in the floorboard of my TB. You think I buy specialized tools??? NOTE: Before and after removing the ring, I vacuumed off all of the rust and crescent-shaped pieces of metal. Using the hammer will knock a lot of rust off. You don't want that in your tank.
I was a bit worried about being able to pull the pump out of the tank, but with the ring removed, the pump pulled out easily.
Pretty clean!
Install your new pump and lock ring. I wouldn't reuse that old, rusty ring. Again, the pneumatic hammer was a necessity. Reconnect the fuel lines and electrical connector. Start your truck to see if gasoline is spewing out like before. It's not. Success!
Paint the edges of the floorboard that you cut so it doesn't rust, then use a nibbler to cut some sheet metal of similar thickness to a little bigger than the hole. Paint it, don't wait for it to dry completely (because who doesn't like paint covered fingers?), put a bead of RTV around the hole, and pop a few rivets in. Self-tappers would work as well, but just make sure they're short.
Replace the padding and carpet. I used some sticky tape to stick the carpet together where I cut. Reinstall the trim pieces and rear seat, and you're done!
Thumb your nose at the internet who said it couldn't be done.
Let the "you're gunna die" comments begin.
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And does anyone know where it would be on mine?