Fuel Return - 95 4.0

4.0 engine swap (out of a 95 Grand Cherokee) into my '81 Scrambler (frame off restoration in progress). The '95 4.0 does not have a fuel return on the fuel rail. My understanding is that in '95 there is no fuel return and a fuel pressure regulator is required, perhaps just after the inline fuel pump??? Any ideas on this, what kind of regulator, what is pressure required?

I have access to a '94 Cherokee (junk yard) and have been getting accessories off of it for the '95 4.0. The wiring harness on the '94 is in really good shape (I did not getting any wiring with my '95 4.0). Any major problems in using the wiring harness and computer from the '94 on the '95? I know that the MAP sensor on the two are in different locations. Thoughts??

Is that year the GC had the regulator/filter combo in the fuel line? If so, using the stock filter/regulator after the pump would be the way to go. I know there was a grand Cherokee that was set up that way, don't recall the years off the top of my head. Even if it's not the stock setup, I know folks run that GC filter/regulator to satisfy both needs, but you'd need to check that the pressure works for your 95, I bet it does.

I used a Mallory adjustable regulator in my 97 4.0 swap. But I tried to go cheap with an eBay regulator that didn't work out. I should have looked into the GC combo option from the start.

The following links should help answer some of your questions.

We swapped a 95 Grand 4.0L last winter.
Grand Cherokee donor is a single line fuel system (no return) the regulator is part of the in-tank fuel pump.
We got the GC pump/regulator/combo, stripped the assembly down to just the GC pump, got a new pickup sock/filter, modified the CJ sending to attach the GC pump to it.
Then used the external/inline WJ filter/regulator. The WJ filter has a return.

WJ filter/regulator we used: Wix 33750

Discussion on cj-8.com on this exact filter/regulator
https://www.cj-8.com/forum/showthread.php?37893-4-0l-fuel-regulator-The-Undiscovered


This thread shows a WJ filter/regulator.
Second page shows the filter/regulator cut apart and it definitely has a regulator built in.

http://www.jeepgarage.org/f196/replaced-fuel-filter-41298.html

Gives some good info on fuel system requirements.
http://www.4wdmechanix.com/Jeep-Fuel-Pressure-Requirements.html


more: (Marty, SoCal is a pretty sharp dude on the 4.0 swap stuff, I have seen many good post with info from him.)
http://www.pirate4x4.com/forum/jeep-non-hardcore/981099-e2000-problems-scrambler-4-0-swap.html

I did this same swap like almost 10 years ago. Bought a takeout from a 95 Cherokee with computer and harness and went to work. Seems like I just put an electric pump in the tank and always had a long crank til I was able to get the fuel system to hold pressure at the rail. Sorry forgot the fix but this was a popular swap then and there should be a ton of old threads on it.

Bob

Unfortunately, the almost universal source for all things 4.0L swap related was cjoffroad.com which died, just noticed that the domain finally changed hands, but has no site, so it's well and truly dead and in the hands of someone who wants to make $$$ selling the domain.

There are threads out there, but many/most links that you will find will include links back to a thread there.

The guy that Jason mentioned on Pirate, Marty SoCal, was a very active guy on cjoffroad with a ton of information to share on these. He helped me with my 97 swap and a few other questions that have come up since.

Hey bigwalton I remember you from the old forum. I also remembered that my 4.0 swap had a long crank time. I fixed it by replacing the fuel regulator which was on the rail. After that it cranked instantly every time. Oh, and the pressure had to be 45PSI.

Bob