rebuilt Np231 problems

[MinnesnowtaDave]

I just replaced my busted old t-case with another NP231 (with new bearings and seals) in it. I got everything bolted up and toped off, time for a test drive. Reved the engine, droped the clutch, but the driveshafts arn't moving.
When had it on jackstands I was able to spin the front and rear axle seperatly, then I could shift and lock them together. I assumed I was goinh from 2hi to 4 hi. After I had it all installed, I put in a rear lunchbox and was unable to get it in nutral, but it seemed to go into 2hi, 4 hi and 4lo ok.
I'll try to adjust the shifter, but I don't think thats the problem since it feels like is shifting, it can't be in nutral all the time can it? There is no chance i bolted the case to the transmission w/o mating the output/input together? I'm lost, please help :?

 

[redrooster]

Sounds like the linkage. See if you can get under it and shift it by hand again.

 

[Bounty__Hunter]

RE: YJ STUFF

Are you sure the replacement transfer case had the proper input shaft? A short input shaft in place of a long shaft may keep the transmission from sending power to the transfer case, and you could still operate the t-case to lock both axles together.

 

[MinnesnowtaDave]

1994 xj parts

Are you sure the replacement transfer case had the proper input shaft? A short input shaft in place of a long shaft may keep the transmission from sending power to the transfer case, and you could still operate the t-case to lock both axles together.

I believe the new one was out of a cherokee. I made sure it had the cirrect number of splines, but I didn't know jeep used NP231s with different length input shafts. If I can't get it to work by shifting, I'll take a look when I drop the case again.

 

[Snitty]

Bounty is on the only idea I could come up with

 

[MinnesnowtaDave]

RE: Front Axle

well, i pulled the case and the input shaft legenth is ok, but the diamiter is way too big. The output shaft was just spinning inside the input shaft without touching it. I've never opened a t-case before, but my idea is to take the output shaft from my old 231 and put it in my new one. Is this workable? I like to think I'm somewhat mechanicly inclined, but is this something I'll be able to figure out on my own?

 

[Bounty__Hunter]

RE: Re: RE: transfer case squeal on 93 yj ??

What did this replacement 231 come out of? Never heard of an incrorrect shaft diameter, if the spline count is the same.

You'll need split-ring pliers to remove the clips from the mainshaft. Other than that it's pretty straightforward. You need to completely disassemble it to get to the input shaft, it will come out with the planetary gears. Then just remove one retaining ring and the shaft lifts out of the planetary gearset. Practice on your old TC first.

 

[MinnesnowtaDave]

NASA Discovery-What is your Opinion??

Thanks, without the split ring pliers recomendation I would have wasted all afternoon trying to get them off with screwdrivers.

I got the input shafts switched up. All I need to do now is fit the chain back on and seal everything up. I'm calling it a day fro now, but I'd appreciate any hints on getting the chain back on, its not quite as easy as on my mountain bike.

 

[Junkpile]

RE: Progress, almost done....

I'd appreciate any hints on getting the chain back on, its not quite as easy as on my mountain bike.

LOL. That's funny :lol:

 

[Bounty__Hunter]

Can I use 24lb fuel injectors in my 4.0L?

Put the chain on the mainshaft and front output before installing them in the case. Then slip the shafts into the front casehalf with the chain installed on the shafts. Sometimes it's easier to have the case face down and drop the shafts in, watch your fingers.

Once you install the rear case half and oil pump over the mainshaft, lift up slightly on the mainshaft to see under the pump to ensure the pickup tube is still fully seated in the pump.

 

[MinnesnowtaDave]

Put the chain on the mainshaft and front output before installing them in the case.

My only problem there is I never took the front output out. There is no way to get the nut off the yolk end since the whole shaft spins when I try to wrench it off. There is nowhere on the shaft to grip it to prevent this.

Edit:
Nevermind, I got a little creative and managed to wiggle it into place. Not only is the chain on, but its sealed up and still sfifts and everything! :shock: I'll get it back in the jeep this week and let you all know how how the test drive goes. Thanks for all the help.

 

[Bounty__Hunter]

You can throw a pipewrench on the outside of the yoke to hold it while an impact loosens the nut. Otherwise you can make a special tool to bolt to the yoke in the yoke bolt holes.

I've been pretty lucky and been able to hold the yoke by hand and hit the nut with an impact.

 

[MinnesnowtaDave]

Update:
I put everything back together last weekend and it seemed to work great when i took it out for a test drive. Haven't taken it off-road yet, but I'm comfident it'll work just fine. Thanks for the help!