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Fuel Pump Replacement (DIY)......

14427 Views 13 Replies 11 Participants Last post by  jwernatl
Car will not start although it cranks as normal.
No sound of fuel pump from rear of car "key on -engine off".
You can hear a small "click" near the passenger side when you turn key to "on".
When you crank you get spark.

Floor Jack
Jack stands
12" plywood or board
Siphon and bucket (if needed)
1/2" socket w/ (6 or 8")extension (3/8" drive)
5/16" socket w/extension (1/4" drive)
rust penetrating oil
Flat tip screwdriver
* a very good friend ( you will understand as you read :) )

Fuel pump
Fuel Filter

Time: Approx. 2 Hours

  1. Disconnect battery
  2. Siphon fuel if needed. .
  3. Jack up car from rear on center of axle housing . Follow normal jacking precautions.
  4. Support car with two jack stands under the rear axle and near the tires. I had the rear wheels about 5" off the ground. Remove hydraulic floor jack (this is used to help lower the fuel tank).
  5. At this point I removed the fuel filter. It is located in front of the tank centered between the rear wheels. Use flat tip screwdriver to loosen hose clamp that holds filter. Next pry on the white plastic (hairpin) clips that hold the fuel lines to the filter (one on each end). There may be some gas leakage when the lines are pulled, ESPECIALLY IF THE LINES ARE STILL PRESSURIZED. Use goggles, rag and bucket to minimize drippings. The clips come out perpendicular to the lines and there is a triangular tab to pry on. Don't break them unless you bought a new filter (it comes w/ two replacement clips). Pull hose off each end of filter.
  6. While under car it is a good time to use some penetrating oil on the two 1/2" bolts that hold the tank brackets to the chassis. They can be difficult. They are to each side of the filter.
  7. Using 5/16" socket w/extension remove 3 screws inside fuel fill door. I also removed 4 screws on the inside of the panel that hold a rubber cover to the backside of the fill door cavity. There is also a smaller size screw that attaches a bracket to the fill side of the tank. It has a loop that goes around the fill pipe.
  8. This whole assembly needs to be loose to drop the tank. You should be able to pull on this assembly, out of the fill door area, and it should start to slide out of the tank. There is a rubber grommet around the fuel pipe at the tank. You won't be able to pull it all the way out until the tank drops a little.
  9. Try loosening the tank bracket bolts now. If still tight try more penetrating oil. (DO NOT REMOVE THEM UNTIL YOU HAVE SUPPORTED THE TANK).
  10. If the bolts are loose put floor jack under the tank center. Use a piece of wood to lift with to distribute the weight. Once the tank is supported you can remove the bracket bolts. I was able to swing the brackets vertical at the height I had lifted my car.
  11. Disconnect: At the rear of the car at center there is an electrical connector that goes to the pump. Disconnect it.
  12. There is a plastic loop at the front of the tank that the fuel lines run through. I cut this but I guess it could be pulled out of the chassis.
  13. While one guy slowly lowers the tank the *friend*can work the fill pipe the rest of the way out of the tank. The gas tank has to be emptied to below this level or it will run out. Always look for lines or electrical connections that might be binding. The tank may want to drop one side more than the other but it was manageable with two guys. We were able at this point to set the tank on the ground without stretching any lines.
  14. The pump assembly goes in the tank on the right hand side (from back of car) on a high spot on the tank. Clean this area as well as possible to prevent dirt from getting into the tank upon removal. I wiped the area and used an air gun to blow dirt away (good idea!). My assembly was oriented with a red electrical plug towards the rear of the car and the two metal lines facing the front of the car. You can take off the electrical plug by using a screwdriver to pry on the catch clip between the plug and the metal lines. The clips on the metal lines are two different types. One is identical to the fuel filter clips (hairpin). The other has two tabs that need to be depressed. The clip comes out the end of the holder and stays around the metal line. You should be able to separate the flexible line from the metal lines.
  15. The pump assembly is held in with a large locking ring. It has 4 tabs sticking up. You should be able to see the three bent over flaps that hold it on and the notches you have to rotate it to in order to remove it. I used some penetrating oil here also. Using a hammer and 3/8" extension tap on one of the tabs to rotate the ring counterclockwise. Do not use a screwdriver, it just bent the tab. Once the ring is off the pump assembly should be free. In my case I had to rotate the assembly 180 DEGREES to remove it. It has a "z" shape to it and takes some wiggling to remove.
  16. At this point you should be all set. Install pump in assembly and reverse.
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Very good.
On mine though, there is an anti syphon fill tube. I don't know if all of them have this, but either syphoning through the filter works, or drop the tank with gas in it (not a challenge) and then jump power to the new fuel pump before reinstalling the tank, and just use the pump to syphon it out.
I just used a jack to help hold it up while I secured it back to the car. Less mess and usually quicker.
This is super easy to do on the stangs. Great write up.
Thanks. I just did my pump and this write up was very helpful. Yours was the only one that mentioned the two types of fuel line connector that had me baffled for a while.

A couple of things I might add are:

- I had most of the gas out and the tank was heavier on the passenger side, so be carefull to keep it in balance.

- Other people suggest using something brass or wooden to hammer off the lock ring, in case of a spark. I used brass, even though I've never actualy seen anything spark when hammering against metal tools.

- Having damaged one of the plastic hose locking clips, I found that PepBoys sells both types :)

- I was able to do the job single handed by using a motorcycle lift instead of a floor jack to lower the tank. I love that lift - I used if for a single handed rear end swap too, and I expect to use it as a tranny jack when the need arises.

- I had a terrible time getting my new pump to go in and fit into the "well" inside the tank. It was a Holley pump with plastic reinforcing on the filter. It was a PITA and I had to get the filter aligned just right to get it in.
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Very good, and it's not that difficult to do. However, before I went to the trouble of dropping the tank, I would double check the pump by grounding the fuel pump test port (on my car, it's located on the plug where you go to pull codes).

If the pump will not turn on, it's definately dead. If it does turn on, the problem is somewhere else. (That was a pure head ache to track down.)
great write up reggie. i did this in my car....should have used another guy to help push the tank up, but no one was around so i used my trusty jack to lift it back up into place....i think CNTLOSE is right it was probably a little easier to do with the jack:bigthumbsup
hey i was just wondering, i know this is dumb but what exactly does DIY stand for?? Diagnose Install Y#%$^& lol
do it yourself!
ah ty vm im not very good with acronyms... as u can see im an accomplished speller HAHAHAHA :laugh:
This is a great write-up and thought I would add some details after I did this for my 1989.

Trust me that having a second person to help is going to make life way easier. You can do everything one person UNTIL it's time to get the tank back up under the car as you need to lift and also angle the tank a bit to make it fit into its home and tighten the brackets up.

Make sure the tank is about 1/8 full as it makes for less chance of sloshing when moving the tank during the re-intall. I had it about 1/4 full and had to go get a siphon to take out more gas. The more empty the tank the better but when the filler pipe is out of the tank you'll get gas sloshing out the side if it's too full.

When you get the tank in, you can get the bracket bolts in a about 2 turns and with them that loose you have enough wiggle room to get the fill pipe into the filler grommet on the tank. Again, this is were person #2 is valuable. I used a borrowed motorcycle jack and still needed some help to get the tank at an angle so the brackets would hug the tank.

My car was garage kept for 95% of it's life and the tank was in immaculate rust-free condition. When I did this job the fuel line elbows on the fuel pump bracket that go into the tank were rusty. I took a wire brush to clean off the rust. Had I known this I would have bought a new fuel pump bracket as I hate doing things twice. I'll live with it until it leaks but in the back of my mind I hate knowing it's like this. I took some rust inhibitor paint and gave a quick blast to the elbows but it's a band-aid at best. Luckily you don't have to remove the fuel lines from the elbows and risk breaking them.

Also, you need a 1/4 inch fuel line disconnect tool ($5 at NAPA) to remove the "duck-bill" connectors. The "hairpin" connectors you can just remove with a screw driver. If you buy the Walbro fuel pump it gives you a spare duckbill connector and if you don't use the tool you'll probably bust it getting it out. My recommendation: buy the tool and don't fight it.

You don't need to cut the platic black hoop the rubber fuel lines sit in on the passenger side of the tank. It just pulls out of the frame and can be re-used. It holds the lines in place away from sharp items and the tailpipe.

Also, plan on a good 10-15 minutes to clean the area around the fuel pump inlet before you can take it off as you do not want any of the grit to get in the tank. That area is a dirt magnet and using an air compressor only got so much of the dirt out. I used a detailing brush and some PB blaster and cleaned the area very well and the time is worth it IMO.

I used a can of throttle body cleaner to neaten up my tank and get it completely clean.

The positive and negative connections on the pump are fool proof as the positive connector is larger than the negative connection.

When putting the pump and bracket back in the tank, you have to kind of fold the filter to get it in the hole. Also, you'll have to wiggle the brack around at bit to get it to fit as there are baffles in the tank and it will hold the bracket from going all the way in. Once you hit the sweet spot it drops right in place.

With the tank out you may find dusty areas or teeny spot rust areas behind the tank on your cars underside. This is a good time to get some 100 grit sand paper and sand/paint them for long-term preservation. You can also paint your brackets at this time too.

I used spray wax and cleaned the area really good before I went to town putting everything back together.

Doing all the cleaning, trip to NAPA, lunch break with wife the whole deal took me about 8 hours. If I just wanted to slap in the new pump and forgo the cleaning/paint and had another person with me the whole time I would say this is a 2-3 hour job for someone doing it the first time. The intial post covers it pretty good.
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i have a 95 GT and the fuse for the pump keeps blowing, i was wondering if it may be a relay or just the pump. i have all the above problems on my car, with the clicking and everything, i told them to have the pump replaced when it was out a couple months ago but they didnt do it. so i think its the pump but im not getting any power to the gas pump switch in the trunk. i dont know if the pump controls the switch or vise versa. or it could just be a relay but i know they hardly go out. any ideas? :sadcry:
fuel pump fuse* sorry about that. it keeps blowing the fuse
This is an awesome article. I think I need to do this. I THINK??

Sunday I was crusing along and my car just quit. I checked spark got one but it was weak so I replaced the coil. Got good spark.

The reason I say that - My pump makes the normal 'humm' it always did when I turn on the key but I dont think I'm getting fuel because I have a fuel pressure guage installed on my fuel line before the injectors. It doesnt move when I turn key on and try to start car.

Can the filter be clogged? Can the pump go bad even though I hear the 'humm??
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