Caincando1

Can someone point me to a step by step instructions on changing my fuel filter. Thanks!

BTW-truck is a 1990.

wheelo90

I just recently chainged mine, here is how I did it.
1) unplug the wire to the sensor on the bottom of the filter.
2) Drain filter by using the water separator.
3) Unscrew old filter, making sure to get the little o-ring with it.
4) screw the water separator back on, and Fill the new filter with fresh fuel
5) Apply a thin coat of oil to the seals
6) screw filter on, and and plug the wires back in to the filter.
You may have to release the air in the filter. (I hope you have a pic of the fuel system, it will show a bleeder bolt on a fuel line). open that bolt and use the lever on the side of the lift pump to purge the air out of the filter. until it squirts fuel out of it. Tighten it,
AND FIRE HER UP!
It will idle rugh for a moment or two then it will smooth out and purr like a kitten. Rather simple and quick process.
Wheelo

Boatnik

Just a caution note; be carful when you twist the filter. the fuel heater wires are plugged into the top of the housing and it is very possible to break the plug if you allow it to twist into the block.

Chrisreyn

Additional caution:
It is possible that the fuel heater may unscrew from teh block with teh filter. You NEED to pay attention to which side is "up" and replace it correctly!!
there is an o-ring similar to the filter o-ring which seals the heater to the block, and it is easy no to notice it is missing untill you are leaking fuel.
Changing the filter is a very easy job, jsut requires attention to detail as you do it.

Caincando1

Thanks guys. I'll take my time and hopefully it will work. I'm just a little worried about trapped air. I'll have to familiarize myself with the bleed screw and the lever pump. I have no idea where they are at, but I'll find them.

bgilbert

As long as you prefill the filter with fuel or fuel additive, you don't have to fool with bleeding anything or messing with a limp lift pump.

Zarrinvz24

Years ago I owned a 2001 Dodge with the 24 valve, and whenever I changed the fuel filter I would put some ATF in there with the filter to lube up the lift pump, apparantly the lube pump is a weak point in the 98.5-02 series. Anyway I just got a new truck and this will be my first as a diesel first-gen. Is it reccomended to put AFT in there with the fuel when we are pre-filling it? Does the first-gen's lift pump have known deficiencies like that?

Palerider

Yes, but dont use ATF, (huge debate on this subject, ATF has friction modifiers to cause friction). Use diesel or diesel additive and put some additive in the fuel for lubriticity.
Dont flame me to hard. I know many of you use ATF, but clutch bands are different than whats in the injection pump even though many have done it for years and used many other things including hydaulic oil and lots of other stuff. Good break down wheelo90.

haultruck

I just did this as I was changing my fuel filter. I didn't realize the top would spin. Luckily I think it only broke the wire side of the plug, should be cheap and easy to replace. My question is this: is the top supposed to be able to spin? I wouldn't think so, but when I went to tighten up the stud that the filter screws on to I couldn't get it to budge. Seems tight. I also never had any fuel leaking before. Does it tighten up with the filter? Appreciate any input/feedback you guys can give me.

bannerd

Tightens with a big screw driver

thrashingcows

The fuel pre-heater is a separate unit, so yes it does come off. It is held in place by the same stud the fuel filter uses. There is a slot in the bottom of the stud that you can use to tighten, and loosen the stud.

There is a seal in the casting of the head that houses an o-ring to seal the fuel pre-heater. If after loosening the pre-heater, and tightening it up you might end up with fuel leaking by this seal. They don't seem to like being disturbed.
You can get a new O-ring from Geno's, or other on-line sources.

haultruck

I worded that completely wrong, let me try again. The fuel heater is loose and spinning with the fuel filter off. I wasn't sure if it should be so I tried to tighten the threaded stud(in the slots, with a huge screwdriver) it's tighter than a nun. My question is, will the fuel heater tighten up as the new fuel filter is threaded on and pressed against it? I'm thinking it has to since it was tight, and didn't leak before. Is tightening the filter by hand enough? Thanks guys

dodgenstein

Heater should not spin with filter off. Something is not right, either something is binding the center stud, or you have a problem with the heater itself.

haultruck

Thanks for the response dodgenstein. Between my last reply and yours, I got home and tested my theory. I'm not sure why but everything's good. Filter's tight, heater is tight, and no leaks. I was pretty happy until I read your reply. Now I'm not sure what to do. I'm thinking I'll order a whole new setup and just watch this one close. Thanks again guys

bannerd

Sounds like you need a new fuel heater gasket. Typically the center bolt threads into the fuel heater and the resistance from the gaskets is more than enough to lock it in. Usually a big flat screw driver works or if you have a newer model you have a allen hex you can tighten with.