Have an 89 4.0 just finished my headder swap was letting her run cjhecking for leaks and I noticed the fuel line going towards the front of the fuel rail running into what I am assuming is the fuel pressure regulator(looks to be a vaccum advance like on a distrubitor on a 350) was dripping gas is there an o ring. Inside the regulator if so how difficult is the removal and will an o ring off an injector fit it .... thanks for looking

So noone has any idea what I'm talkiing about or dealt with this before????

i cant remember if there is an o ring or not i changed mine because i let part of an injector oring run through the fuel rail. its not hard to get off though just one bolt and a little wiggling

Yes there is an o ring. No an injector one will not work

pieced together on my iPhone using my uber l337 hax skilz.

What would I ask for at the parts house a fuel pressure regulator internal o ring perhaps

pull the old one out and match it up

K thanks

Good luck! If you where close to me I would give you a whole new rail lol I have like 3

pieced together on my iPhone using my uber l337 hax skilz.

I know exactly what you're talking about...

If it's where the fuel pressure regulator connects to the fuel rail, it's the same as the fuel injector O-rings (this is why the OEM kits come with thirteen O-rings, instead of twelve.)

If it's where the line connects, get a "fuel rail connect renew kit" from the dealer - get two, one for each end (the supply line at the rear, and the return line at the regulator.) The kit will have new Nylon retaining ears, two new O-rings, a Nylon spacer collar, and a Nylon mandrel to install it all.

FOR THE FUEL RAIL CONNECTION:
- Throw the new O-ring in a bit of clean fuel
- Remove the fuel pressure regulator
- Remove the O-ring from the fuel rail snout
- Put the new O-ring on the fuel rail snout (it should have been soaking in fuel for a good fifteen minutes by now. If you're been efficient, take a short break so that the new O-ring soaks for a minimum of fifteen minutes.)
- Insert the fuel pressure regulator snout into the end of the fuel rail
- Reinstall retaining screws for the fuel pressure regulator to the fuel rail. You should not have needed to remove the fuel rail proper to do this job.

FOR THE LINE FITTING:
- Squeeze the ears and remove the old line.
- Using a pick, remove two O-rings and one Nylon spacer collar from the female side of the fitting. Check the male side first - any parts you find stuck on the male tube you wont find in the female socket, and I've had parts come out with the tubing before.
- Insert the new assembly until you hear a "click."
- Squeeze the Nylon ears and remove the Nylon mandrel.
- Insert the line, press until you hear it "click."
- You're done. You will not need to remove the fuel rail assembly to get this done, unless you're doing fuel injector O-rings as well.

The theory goes that the line O-rings are replaced every tine the line is removed - which is good advice. Do not get hardware store O-rings - they're not fuel resistant, and will dissolve. This is a Very Bad Thing(tm). You will probably need to remove the return line from the regulator in order to service the regulator-to-rail O-ring - so plan ahead.

Soaking the large O-rings in fuel makes them pliant for installation, and soft so they can seal against the surface more quickly. This is generally not necessary for the small line O-rings, since there are two of them and they'll back each other up.

Wow thanks for the info its the small line o rings I actually replaced the o ring inside the fuel rail when I did my injector swap do u think a parts place will have the kit? Or is this a dealer only part thanks everyone for all the help I have learned so much about my jeep in such a short period of time

I have not found the kit in the aftermarket yet - doesn't mean it's not out there, just that I haven't seen it.

I usually end up going OEM for it, expect it to run about $15. Buy a few extras, keep in cool dark place to preserve the O-rings.

sorry to thread jack but would this regulator be the only thing that would cause 3x too much fuel?

Here ya go.......

Quick disconnect part numbers

So far the Napa part numbers for just orings is:

Napa 730-5018 3/8 Viton individual orings $1.56 each
Napa 730-5017 5/16 Viton individual orings $1.35 each
Napa CRB 212305 fuel line repair kit 5/16? $15.93 each


Mopar repair kits:

83502745 fuel line repair kit 5/16 $6.99 Morris
83504447 fuel line/Trans line repair kit 3/8 $8.99 Morris

Thanks Randall.

No thank you. IIRC I got those #'s from you.....he.....he......

Great replacement kits & very easy to use.