Fuel Pump Replacement

[Quick Pony]

Well, I got a few more days out of my original fuel pump on my 1991 Mustang LX.5.0 convertible. It crapped out yesterday and I had to be towed home.

1. What manufacturer and lph should I go with for a direct replacement?
2. Any other parts I should replace when I replace the fuel pump?
3. How difficult is it to pull the gas tank?

Thanks as always.

Larry (91 LX 5.0 convertible)

 

[MARX91]

i went w/ a walbro 190lph, you might as well change the filter while your at it, and use something brass to tap
the fuel pump ring loose so there arent any sparks
the gas tank isnt really too hard to drop
www.my5oh.com

 

[HISSIN50]

As mentioned above, Walbro is OEM and most of the pumps out there are repackaged Walbro's anyhow.

Do buy from a reputable vendor as there are some fake Walbros out there.

You'll need a new tank grommet. About 20 bucks at the dealer.

Droppin the tank is easy.

Goo luck.

 

[bullitstang1313]

You might also throw in a new fuel level sender while you are down there. I know I have seen quite a few of them go bad.

 

[PhLoBuS]

lowering the tank will not damage any lines will it? is there a certain technique on lowering it to make sure its not damaged. Also one of the hoses will not fit over the fuel filter opening. any suggestions>

 

[Anthony85stang]

You have to lower the tank enough to were you can get your hand up in there to pop the clips and get the lines off. Like said above i woul definetly change the filter (some companys void the warrenty if you dont) and you might as well change the sender while you got it out.

 

[PhLoBuS]

yeah I already put a new filter in

 

[HISSIN50]

I use a sheet of something big (like plywood) on the saddle of my jack. Then use the jack under the tank to lower it down - nice and slow and you can watch the lines.

I don't understand what you said about one of the lines not fitting over the fuel filter opening. Please rephrase.

Good luck.

 

[lxarlo]

hopefully you dont have that much fuel in the tank, so its light and less of a chance of dropping it from the jack. what you might want to do is like stated before, definately get a new filler neck grommet, and if you get just the pump, get a new o ring seal which seals the fuel pump access. unbolt the filler neck at the gas filler door, undo the fuel filter, and undo the straps with the two bolts. if i were just goin for a direct replacement, i would just get another one from ford. its a little pricey, but you get new everything, pump, sender, float, pump sock, and plastic housing assembly, tubes, and the top seal. but thats just me. for good measure though, before you open the fuel tank, be sure to blow off the top of the tank with compressed air if available, because there is goin to be alot of dirt collected from 16 years. and you dont want that in the tank.

 

[jrichker]

Here are some useful tips...

I have done the tank removal twice, and the main issues are getting the car up on jack stands and getting the gas out of the tank. DO NOT try to do this job without jack stands. Becoming a pancake is not part of the repair process.

Some 5 gallon paint pails lined with garbage bags are good to hold the gas. The garbage bags provide a clean liner for the pails and keep the loose trash out of the gas so you can reuse it. A piece of 1/2" garden hose stuck down the filler neck will siphon all but a gallon or so of the gas.

Remove the filler neck bolts and put them in a zip bag. Disconnect the supply & return lines by removing the plastic clips from the metal tubing. If you damage the clips you can use tie-wraps as a substitute when you re-assemble them. Then you remove the two 9/16" nuts that hold the T bolts to the straps. Put the nuts in the zip bag with the filler bolts. Pull the plastic shield down and away from the tank. Once the tank drops a little bit you can disconnect the wiring for the pump & fuel quantity sender.

The pump assembly comes out by removing a large metal ring that unscrews from the tank. You are supposed to use a brass punch to tap on the ring so that you don't make sparks. Look closely at the rubber O ring gasket when you remove the sender. The pump assembly requires some twisting and turning to get it out the hole.

Look very closely at the electrical wiring. The stock wiring can overheat and melt the insulation. Mine had some really crummy plastic tubing slid over the quick disconnects. If the wires ever got together, there would be sparks inside the fuel tank and no more Mustang. I eliminated the splice in the middle of the wiring and went straight from the pump to the feed through connectors for the wiring. It required some soldering and crimping of new tabs on the wires, but it made a neater job.

Inspect the pump mount to metal tubing bracket. Mine broke and I couldn't get it to solder back together. I drilled a small hole for a machine screw & self locking not to hold the clamp and bracket together.

The pump is easy to get off the mount but is somewhat difficult to get back it the tank without damaging the sock filter or tearing it on the tank baffle. When you install the metal ring that holds the pump in place, watch out for the gasket O ring. Some RTV may be helpful if the ring is not in excellent condition.

I used a floor jack to help lift the tank back in place. You may find that it is the only time you really can make good use of a helper.

 

[bubba-dough]

This is a pretty good page of instructional downloads from 50resto.com http://www.latemodelrestoration.com/downloads/instruction-sheets.aspx Its a pretty easy and straight foward job. As said before most pumps are repackaged Walbro pumps. Just order a name brand from a good place. If its gonna stay stock or near stock a 110 would be fine but if you plan on future mods go with something larger. The price difference between the lph is minumum and the stock fuel pressure regulator will keep everything under control.
Things to also change would be the grommet and fuel filter.
Something to keep in mind is to make sure to remove as much fuel as possible (you don't want to find out while lowering the tank that it has to much fuel in it and its hard to handle).
Also like stated somewhere above a blow gun is handy or take your time and clean the top of the tank off well. You don't want to get anything in your tank.

 

[Flavadave4]

pop the clips before you let it down all the way!