Getting ready to start an XJ build

upnover

upnover

Grumpy, decrepit Old Man
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Joined
Mar 20, 2005
Location
Morganton NC
OK, this may be long.

Acquired a 89 XJ. I have never owned one, for that matter, never owned a fuel injected Jeep before. Yeah, I am still in the dark ages! It has a 4.0 with a 5 speed.

First off it doesn't run. I am pretty unsure of what to do to make it run, like I said, I have only owned one fuel injected anything, and have done little work to it. So, with that in mind. I charged the battery yesterday, and turned it over. With just the started and old as the hills oil in it, it built up about 40lbs of oil pressure. It has the rail system on it, not throttle body. I saw where there was a small tire valve looking piece in the side. I took off the cap and pressed in the release, and go a very small spit of gas. I then had my son to turn it over, and I pressed it in as he turned, and no more gas. So I assume it's a fuel line, pump, electrical, filter type of issue. I was told that at some point it was supposed to have been leaking gas. So with that in mind, any suggestions on what to look at first to track down the problem will be appreciated.

Ok, to move on to the build. This will be a budget build. So far investment is Zero, outside of the cost of fuel to go get it. Yes, it was free. I have located a set of CUCV one ton axles, 14 bolt rear with a Detroit, and a Dana 60 front with limited grip, for a $1000 bucks. This is for my son/wife to drive, with my son footing most of the funds for the build.

I have always heard that the frame or unibody on these things are one of the weak points. I am open to suggestions on what to do about this. One idea I have is putting it on a blazer frame, that I already have. I have seen one, but have never really looked at it to see how/what he did. I actually think he bought it that way. My reason for doing this is to give a good place for mounting an exo cage. Axles will be for the most part bolt in. I can run stock springs and with some fender trimming and run about what ever tire size I want. Beefy front and rear bumpers will be a lot easier to build, mount, and stronger. Thoughts on this welcome as well.

I think I read that the output shaft on my tranny is a 21 spline. I want to run a Dana 300 so an adapter kit will be necessary. Or, would it be more cost effective to fine a 23 spline 5 speed tranny? Again thoughts appreciated.

High steer/crossover arms will be installed, already know where I will get those. I know the frame on the Chevy will have to be re-enforced. Has anyone ever put a CJ style box on a Chevy? Only reason for this consideration is I can tap a CJ box for hydro assist. But, I am not sure about the shaft clearance and so on. Comments welcome

Ok nuf of all this. I will add more as my thoughts, and questions come to mind.
 
What kind of budget build are you talking about?!?!

I beleive the fuel filter/Pump is inside the gas tank on those.......

Check for blown fuses..... (cross fingers.....)
 
rbo1577186 said:
What kind of budget build are you talking about?!?!
I beleive the fuel filter/Pump is inside the gas tank on those.......
Check for blown fuses..... (cross fingers.....)
Click to expand...
What kinda budget? hmm good question. Have not really set down and put together any numbers. Doing most of what I have to do with things I have. Getting the rest as I go.
I figure
dana 300 $200ish
Drive shafts$???
Brake lines$???
ahh heck, if I start pricing it now, it may skeer me out of it LOL

Yeah, already thought about blown fuses, just hadn't checked into it. But with the fuel leaking problem, I am gonn look see what I find there first. As far as this goes, it could be multiple things wrong with it
 
I believe you have a 23 spline output on that tranny. Try to throw fuel directly in the throttle body to see how it runs before you throw any monay at that motor. Also try to beat gently on the tank to see if the fuel pump will start running. rubber mallet usuallly works.

The red xj on the blazer chassis, Tennessee off road stickers on the side. It was bought like that, he is a freind of Kyle's at 4wp. i cant remember his name, Jeff maybe?
 
:uzi: :handed: ya unibody weak point- do the doors open & close well? If so your jeep is still probably straight other than door hinge pins poor alignment of the doors & opening is the first sign of a crooked unibody-under the cherokee you will see what will look like 2 frame rails they are actually pressed into the bottom pan of the unibody it will stiffen the entire structer if you box these in with 3/16 plate with 1" holes in the plate about every 6 or 8" on all 3 sides then rosette weld (plug weld) the holes to the unibody & stitch the seams this will also give you good attachment points for a home made longarm kit to hold thos big axles- when & if you do this make sure you dont forget about the crossmember I would weld & extra piece of 1/4 plate where needed & drill & tap thru both 1/4 & 3/16
or a tapped 1/2" pad I have done this in the past & it worked pretty well hope it helps
 
greg slade said:
I believe you have a 23 spline output on that tranny. Try to throw fuel directly in the throttle body to see how it runs before you throw any monay at that motor. Also try to beat gently on the tank to see if the fuel pump will start running. rubber mallet usuallly works.
The red xj on the blazer chassis, Tennessee off road stickers on the side. It was bought like that, he is a freind of Kyle's at 4wp. i cant remember his name, Jeff maybe?
Click to expand...
Yeah, Jeff is his name. I have rode on the trail with him a few times, but not lately.
 
Just remember that a fuel injected engine runs the same as a carburated one. It just has a computer to control the fuel injectors and a bunch of sensors to tell the computer what the engine is doing and which cyl is next to be fired. They're a bit more complicated but worth it in the end for just about every reason. The tire type valve on the fuel rail is one of the greatest things added to any engine. You can check fuel pressure (Or if you even have any fuel for that matter) without pulling anything more than the cap. (Wish they all had that). You also need to check for spark the same as if it were carbed. Also might want to check code to see if it has any sensor problems. (If it has a bad crank or cam sensor it probably won't start since the computer doesn't know what injector to fire.) First things first though. Get some carb cleaner and spray into the throttle body to see if the engine will actually fire and ture over.
 
Here's my take since I have a 93 and my brother has a 89 XJ. For the fuel issue you can sit under the car by the fuel tank and see if it turns on when you turn the key to the on position. You should hear it. If not it's a fuel pump and they are easy to change. all you have to do is unsrew the giant retainer ring that holds it in. I did this for my brother. Remember the autozone/advance pumps are wired backwards so you might need to switch the wires before you start if that is the case. I would use some starting fluid to see if would start first as well. I played hell with my brothers Jeep not wanting to run. I ended up changing the CPS and it was fine after that. of course in my endever to get it running better I replaced a lot of stuff to include the valve stem seals and it runs like a new one now. It only has 139k on it too.

As for strengthening the frame check out www.tntcustoms.com frame stiffeners for $169.99 Makes it easy to fix and saves a ton of time. The next question would be how you plan to lift it. And that comes down to the type of set up you want to use whether it be 4 link or leaves or even using radius arms like on the Fords. I am getting ready to do the ford radius arms thing. I guess we need a little more info but you can get a ton of info from www.naxja.org Good luck Doug
 
better go with this great link this is almost the same as I did but not at all this cheap wish I knew about these guys then
 
upnover said:
I think I read that the output shaft on my tranny is a 21 spline. I want to run a Dana 300 so an adapter kit will be necessary. Or, would it be more cost effective to fine a 23 spline 5 speed tranny? .
Click to expand...
AFAIK, all 6 cyl have the 23 spline, and 4 cyl have the 21 spline. A d300 would swap right in. and if you're going with GM axles, give you the pass drop, You can also try one of the 231 doubler kits to go in front of the d300, then it doesn't matter what spline your tcase is.

I wouldn't bother trying to put a frame under it, lots of time/work for little gain. And long arms will outperform front springs anyday, as well as a better on road ride

just my $0.02
 
it all depends on the tranny that is in the jeep.... the early XJs had the Peugot(sp) tranny in them and i believe it was 21spl... one way to tell is to see if the tranny has a seem running down it in the middle where it comes apart...

the D300 will bolt in to a 23spl output tranny... and be pass side drop for the axle, even though the floor may have to be clearenced to fit it in, as well as the other issues when changing to PSD... so you may wanna think about tradin that chevy 60 for a HP60 and keepin it DSD

if it were me, id get a AX15 or NV3550 or even an older jeep tranny such as a T18,T5, etc(any will bolt up) to put in its place because the Peugots arent worth the alum theyre made of (along the strengths of a 4cyl AX5)


also putting a frame underneath it would be a big job.... and still maybe unstable afterwards.... the unibodys can be made strong through plating... and even if you wanna ditch the coils, leafs can be put on the XJ frame easily
 
1987-89 Cherokees with the 4.0 motor came equipped with 21 spline transmissions (both auto and manual)
I believe in '90 the switched manual tranny's from the Peugeot BA10 (garbage) to the AX-15. ( 23 spline outputs)
The dana 300 has a 23 spline input. ( link )

There is no adapter made that I am aware of for a 21-23 spline conversion.
the 300 swap also typically requires a spacer/clocking ring to mate properly. There are a few suppliers for this. ( link )

a 23 spline ax-15 or NV 3550 in good running condition will usually cost mucho $$$'s.
If you're not devoted to a manual consider swapping in an auto. The AW4 is a very solid tranny and will take a lot of punishment with a good cooler plumbed in. they are in plentiful supply and can be had relatively cheaply.
It is electrically controlled but www.awshifting.com has a relatively cheap solution for that.


If you're putting fullwidth 3/4+ ton axles underneath of it you probably want to plate the uniframe. Elliot has some good tech on the different plating options and their pros and cons in his thread.(link )

As for your no-start condition:
I would start with the CPS (Crankshaft position sensor) If that's a no go then there are a couple other sensors that could be the cause along with the fuel pump as suggested by others.


search around on Naxja and you can find a lot of good info.

good luck
 
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