87xjco
NAXJA Forum User
- Location
- Denver, CO
NP231 transfer case out of a 1987 XJ
Remove 1 1/8" nut and tap off front output yoke, the instructions say to put the transfer case into 4low and remove the shifter lever. I did not remove the lever and had no problem.
Remove the speedo gear housing and note the position that it was installed in.
Remove the 3 15mm bolts around the rear output slip yoke housing.
Remove the snap ring next to the bearing
A gasket scraper can help split this housing from the rear case half. Be carefull to not gouge the rear case half surface.
After housing removed you see the oil pump and shift fork shaft
Remove the bolts around the transfer case so you can split the two halves of the case. There is this 12point 10mm bolt and two 15mm bolts with washers on them, note the location of these. The rest of the bolts are all 15mm with no washers.
There are 2 slots like this that if you carefully drive a large flat screw driver into, will split the case without damageing the gasket surfaces.
After case is split
Wiggle out the front output shaft and remove chain and set aside
Wiggle out the main shaft and set aside
Two gears and a sincro stay on the shaft as it is removed
You will need to transfer the two gears and sincro onto the new mainshaft
Some older model transfers like mine have caged bearings that need to be discarded, use a brass punch and set the gear on a wooden block to avoid damage as you drive them out.
After the caged bearings are removed, clean and pre-lube gears
Supplied snap rings and hardware, the two matching rings are for the speedo gear and the other is the gear snap ring.
Install gears and put on the new snap ring supplied.
If you set the case flat it is easy to first wiggle the main shaft in thru the sincro shift collar and into the splines at the front of the case. Then install front output shaft and chain together, wiggle and turn the shaft to get it to slide in.
Then install a thin layer of silicone.
The rear case half installs by sliding over the main shaft and making sure the splines for the oil pump do not bind up. Once in place make sure the oil pump tube is still seated in the oil pump at the bottom of the transfer case
First put on the forward snap ring and then slide on the speedo gear and then install the rear snap ring
Now I ran into a problem, the shift fork shaft slides in and out of the rear case half when the gears are shifted. You can see by the depth of the pens that the old housing had a deep enough hole that the shaft had full movement. The new supplied housing does not have a deep enough hole.
So I am stuck until I can call PORC and see what the deal is.
I will post when I know what is wrong.
Remove 1 1/8" nut and tap off front output yoke, the instructions say to put the transfer case into 4low and remove the shifter lever. I did not remove the lever and had no problem.
Remove the speedo gear housing and note the position that it was installed in.
Remove the 3 15mm bolts around the rear output slip yoke housing.
Remove the snap ring next to the bearing
A gasket scraper can help split this housing from the rear case half. Be carefull to not gouge the rear case half surface.
After housing removed you see the oil pump and shift fork shaft
Remove the bolts around the transfer case so you can split the two halves of the case. There is this 12point 10mm bolt and two 15mm bolts with washers on them, note the location of these. The rest of the bolts are all 15mm with no washers.
There are 2 slots like this that if you carefully drive a large flat screw driver into, will split the case without damageing the gasket surfaces.
After case is split
Wiggle out the front output shaft and remove chain and set aside
Wiggle out the main shaft and set aside
Two gears and a sincro stay on the shaft as it is removed
You will need to transfer the two gears and sincro onto the new mainshaft
Some older model transfers like mine have caged bearings that need to be discarded, use a brass punch and set the gear on a wooden block to avoid damage as you drive them out.
After the caged bearings are removed, clean and pre-lube gears
Supplied snap rings and hardware, the two matching rings are for the speedo gear and the other is the gear snap ring.
Install gears and put on the new snap ring supplied.
If you set the case flat it is easy to first wiggle the main shaft in thru the sincro shift collar and into the splines at the front of the case. Then install front output shaft and chain together, wiggle and turn the shaft to get it to slide in.
Then install a thin layer of silicone.
The rear case half installs by sliding over the main shaft and making sure the splines for the oil pump do not bind up. Once in place make sure the oil pump tube is still seated in the oil pump at the bottom of the transfer case
First put on the forward snap ring and then slide on the speedo gear and then install the rear snap ring
Now I ran into a problem, the shift fork shaft slides in and out of the rear case half when the gears are shifted. You can see by the depth of the pens that the old housing had a deep enough hole that the shaft had full movement. The new supplied housing does not have a deep enough hole.
So I am stuck until I can call PORC and see what the deal is.
I will post when I know what is wrong.
