elec. fuel pump 101

[chevyjeff]

I think I need to replace my electric pump in my 90 v10. is there any tricks or tips anyone has before I go bench press this 1/2 full tank of gas. looking to get an ac delco pump. I have power at connector by tank during "on for 2 sec" and while cranking but no sweet hum of the pump. So I assume its toast. Was thinking I might do the cut a hole in floor to access the sending unit but trying to figure out the correct location for the hole could end up being a cluster f. and it would be better to drop the tank. Luckily my truck has no rust so it should be a clean drop but looks like it could be a p.i.t.a.

 

[dyeager535]

I've heard of people tapping the tank and getting the pump to run, if you can get it running, you could disconnect the hard feed line and run a hose to a bucket or something and let the pump drain the tank.

Also, if you get a hard line loose, you CAN siphon through the pump. Left one of my hard lines loose on install, fired the pump up for a split second, left the truck, came back to a nice puddle of fuel on the ground that had been dripping the whole time I had been gone. (hours)

It may take some time, but it will be a lot easier to wield empty of course. A floor jack with a piece of plywood on it will help hold it in place while you unbolt it and try to lower it. More than likely if it has fuel in it, eventually it will slide off the floor jack as the fuel sloshes, but it will keep it from smacking the ground or your head.

Pull the fuel fill lines off before you drop it, so you can get good leverage on them, remove the ground wire from the frame, disconnect the fuel pump/gauge wire connector, then drop the tank a bit so you can disconnect the fuel lines. Be sure to use a tubing wrench on those.

I find it much easier to pull the bumper to get the tank on/off.

 

[chevyjeff]

UGH! removing bumper, reciever hitch, draining gas, lookis like cutting a hole in the floor would be way easier. Found an old post about cutting the hole and using an old truck bed floor section to make a cover. This way I could fix it again on the trail or roadside if needed.

 

[ntsqd]

I'd give serious thot to putting a non-efi sender/pick-up in there and go to a frame rail mounted pump. That way a trail/roadside fix doesn't involve dropping the tank.

 

[surpip]

when i dropped my tank to put the shakle flip in I:,
used 2 ratchet straps, from the bumper to the crossmember, right next to the tank straps.
tightened them up, unbolted the straps witht the tailgate down(did not remove the bumper, but i could see how a hitch could get in the way) and that was it, i let it down a little bit, undid the hoses, let it down all the way.
than i put it up in reverse order with the straps, super easy!!!!!
my tank was at 3/4's

 

[chevyjeff]

gm should have designed an hatch to get to these pumps. f'n engineers. it was real fun too replacing the oil pressure switch when the brittle aluminum extender broke off in the block as soon as i put a wrench on it. Had to take out dist. then get an easy out to get remains out of block and then reassemble. Im cutting a hole and ill make my own hatch to get to the sending unit.

 

[dyeager535]

I didn't pull the hitch to get my tank in or out, so that's not something you'll have to deal with. Skid plate if present needs to come out, but that can be finagled around the hitch.

If you are comfortable cutting a hole, go for it. I figure as long as I put the right parts in there, I won't have to worry about it for another 20 years or so. (and even if I do, all the bolts are now rust-resistant and looser now anyways lol)

 

[chevyjeff]

I went ahead and cut a 12" long by 6 1/2" hole last night and i was done and back on the road in 2.5 hrs. I am very happy to have done this instead of dropping tank. Especially if you have to do this job alone. I will come back tonight and fab a mount for the part of the bed i cut out and seal it up. I used my saws all with a blade that i shortened so not to cut any vital parts. I verified centerline of sender then went 6" front and back for horizontal cut lines then I used the mid point of two high ribs @ 6 1/2" approx to make my cut. I have a couple pics I vadered from another post on ck5

 

[opfor2]

Can you post some pic's? Also, what are you going to use t\as a replacement cover for the hole?

Dan..

 

[chevyjeff]

I cant post pics because im a cheap azz (non member) i can give you a link to the post i found w/ pics. i used them as a guide for the width of the hole and marked the centerline of sender and offset 6" front and back. The centerline of the sender is approx 13 3/8" from the rear edge of the bed
heres the link.
http://coloradok5.com/forums/showthread.php?t=95761&highlight=FUEL+PUMP+HOLE
as for the replacement cover i will most likley fab up a mount to screw the piece i cut out back down and seal it w/ some black permatex