First get the car up in the air.
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I like ramps for this for a couple reason. It keeps the axle tucked up under the car instead of hanging down in your way. It also keep you from having to work around jackstands under the car itself. Not to mention it's easier to just back up ramps instead of dragging out jacks and stands and stuff.
Once you have it up in the air, now's the time to look and see if you need to clean under there before getting started. If your car's spent alot of time up north it might not be a bad idea to spray some lube on the exposed threads to the strap bolts.
Since I'm in the south and drive in the rain, the car stayes pretty well pressurewashed.
Unplug your hotwire feed (you do have a hotwire feed, correct?) and ground strap if you have one.
Remove the two bolts holding the front of the tank straps and let them drop out of the way. A five gallon bucket makes a great rest for the tank to sit on for the next step. Be cautious of the filler neck. If your rear fillers are brittle, you don't want bash into them.
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Now that the tank is resting on the bucket, you have enough room to disconnect the three hoses and the tank will be free.
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Set the tank on the ground and move it out in the open. Go accross the top of the tank with a broom or compressed air to get all the loose debris out off the tank.
Carefully remove the retaining ring that holds down the pump hanger. Keep in mind you're beating on 14 gallons of explosive fumes. Technically you should be using a brass drift or other non sparking device. Me, I like to live on the edge.
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Take note that the retaining ring doesn't fit worth a damn. This is important during the reassembly.
Now that the ring is loose remove the hanger. It's not that delicate to get out but you do have to take your time as the fuel level sending unit is on the hanger too. Cover the tanks hole and move on to the workbench.
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The old pump pretty much just pulls apart. Start from the bottom and push the fuel sock through the hole. Then pull the pump and pulsator from the hanger.
Throw the pulsator in the trash and look at the solid feed pipe on the hanger. Notice it necks down and then has a rolled edge. The ID of that feed tube is .300" and the opening of that rolled edge is .200". Needless to say that sucks.
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I've found a dremel with a large cutoff wheel will make quick work of that area. The body of the tool will make the cut a little angled, but that really doesn't matter. After cutting make sure to deburr the inside and outside edge. The outside is going to be important because the 5/16" hi-pressure fuel hose is going to be a tight fit. No need to cut the inner hose lining. If you bought the pump as a kit from a turbo Buick vendor it most likely comes with the hose and the two clamps. If not a trip to the parts store in needed. Don't forget the two hose clamps too. Since this car had already been done by a non TR tech, I had to source a new hose. Make sure to get the hi-pressure FI hose. You'll be able to tell because it'll be printed on the hose and cost a little over $15 for a two foot pack.
You'll also notice the other side of the feed tube has a pretty small opening at the tip. I knocked off about 1/16" off the end to let that hole open up a little too.
Reassemble the hanger using the hose instead of the pulsator, hook up the wiring and you're ready for reinstallation.
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Clean the O-ring, the area where the ring sits, and the same thing on the hanger. Place the assembly back in the tank noting the tab that keeps it lined up right and carefully put the retaining ring back in place. Spread the impacts out accross the three tabs as you'll notice the ring is too small for that bore. You need to keep walking it around trying to keep it centered. The fit is loose enough that one of the tabs can pop out if it goes too far to one side.
After that's done installation of the tank is the reverse of removal. The only thing to note is when you get the tank in place make sure the wiring isn't pinched. You should be able to move it back and forth even with the tank fully seated.
Now the pump doesn't have to work as hard to move fuel. Since it runs wide open all the time it'll move more. And more is better!
If you suddenly run rich at WOT it worked!
On a side note for the northern cars. I've heard stories of rust forming under those rubber isolation bands. If a tank is on the verge of leaking and the rubber is acting as a seal, doing this might reveal a leak. If you have a rusty tank it might not be a bad idea to spend some time cleaning and checking for signs of cancer. Sometimes PM is easier than waiting untill later. Not to mention cheaper since these are baffled tanks just for turbo cars.
I like ramps for this for a couple reason. It keeps the axle tucked up under the car instead of hanging down in your way. It also keep you from having to work around jackstands under the car itself. Not to mention it's easier to just back up ramps instead of dragging out jacks and stands and stuff.
Once you have it up in the air, now's the time to look and see if you need to clean under there before getting started. If your car's spent alot of time up north it might not be a bad idea to spray some lube on the exposed threads to the strap bolts.
Since I'm in the south and drive in the rain, the car stayes pretty well pressurewashed.
Unplug your hotwire feed (you do have a hotwire feed, correct?) and ground strap if you have one.
Remove the two bolts holding the front of the tank straps and let them drop out of the way. A five gallon bucket makes a great rest for the tank to sit on for the next step. Be cautious of the filler neck. If your rear fillers are brittle, you don't want bash into them.
Now that the tank is resting on the bucket, you have enough room to disconnect the three hoses and the tank will be free.
Set the tank on the ground and move it out in the open. Go accross the top of the tank with a broom or compressed air to get all the loose debris out off the tank.
Carefully remove the retaining ring that holds down the pump hanger. Keep in mind you're beating on 14 gallons of explosive fumes. Technically you should be using a brass drift or other non sparking device. Me, I like to live on the edge.
Take note that the retaining ring doesn't fit worth a damn. This is important during the reassembly.
Now that the ring is loose remove the hanger. It's not that delicate to get out but you do have to take your time as the fuel level sending unit is on the hanger too. Cover the tanks hole and move on to the workbench.
The old pump pretty much just pulls apart. Start from the bottom and push the fuel sock through the hole. Then pull the pump and pulsator from the hanger.
Throw the pulsator in the trash and look at the solid feed pipe on the hanger. Notice it necks down and then has a rolled edge. The ID of that feed tube is .300" and the opening of that rolled edge is .200". Needless to say that sucks.
I've found a dremel with a large cutoff wheel will make quick work of that area. The body of the tool will make the cut a little angled, but that really doesn't matter. After cutting make sure to deburr the inside and outside edge. The outside is going to be important because the 5/16" hi-pressure fuel hose is going to be a tight fit. No need to cut the inner hose lining. If you bought the pump as a kit from a turbo Buick vendor it most likely comes with the hose and the two clamps. If not a trip to the parts store in needed. Don't forget the two hose clamps too. Since this car had already been done by a non TR tech, I had to source a new hose. Make sure to get the hi-pressure FI hose. You'll be able to tell because it'll be printed on the hose and cost a little over $15 for a two foot pack.
You'll also notice the other side of the feed tube has a pretty small opening at the tip. I knocked off about 1/16" off the end to let that hole open up a little too.
Reassemble the hanger using the hose instead of the pulsator, hook up the wiring and you're ready for reinstallation.
Clean the O-ring, the area where the ring sits, and the same thing on the hanger. Place the assembly back in the tank noting the tab that keeps it lined up right and carefully put the retaining ring back in place. Spread the impacts out accross the three tabs as you'll notice the ring is too small for that bore. You need to keep walking it around trying to keep it centered. The fit is loose enough that one of the tabs can pop out if it goes too far to one side.
After that's done installation of the tank is the reverse of removal. The only thing to note is when you get the tank in place make sure the wiring isn't pinched. You should be able to move it back and forth even with the tank fully seated.
Now the pump doesn't have to work as hard to move fuel. Since it runs wide open all the time it'll move more. And more is better!
If you suddenly run rich at WOT it worked!
On a side note for the northern cars. I've heard stories of rust forming under those rubber isolation bands. If a tank is on the verge of leaking and the rubber is acting as a seal, doing this might reveal a leak. If you have a rusty tank it might not be a bad idea to spend some time cleaning and checking for signs of cancer. Sometimes PM is easier than waiting untill later. Not to mention cheaper since these are baffled tanks just for turbo cars.
