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D30 Vacuum Problems?

fasta76

NAXJA Forum User
Location
Vernon
Hey Guys..

Yes i have done a search and have not been able to find what im looking for!! I have an 89 XJ Sport. Inline 6,4+4 With the auto trany And 231 Transfercase.. My problem is that i can not find a diagram for the vacuum line set up for the front end? The problem is that with all the hoses hooked up it will not go into 4wheel.. If i unplug the single green line on the outside of the acuater it will work but then not go back into 2 Wheel? the transfercase will but not the frontend Unless i plug it back in? So im looking for a diagram with the colours of the vacuum lines? Not sure if anyone can help but thought i would ask!!

Thanks in advance..

Tom
 
I don't have the answer you are looking for but I suggest you just go with a cable system and get rid of the vacuum. I made my own out of bicycle cable and a throttle control from a lawn mower. Good luck though.
 
Information I've collected or found from working on a 1990 w/vacuum disconnect: First check all lines, and the vacuum reservoir located in the end of the front bumper (passenger side) for leaks. At t-case switch, there are four vacuum lines. For your 1989 the colours may be different, but it will work the same. Red line-vacuum supply to the t-case switch. Green-has vacuum when in 2wd. White (Yellow on a different 1990!) - has vacuum in 4wd. Blue- goes to the switch that turns on the 4wd dash light or to a checkvalve/filter dead end (not sure on the blue one). First step is check all the lines for leaks or breaks, then check that the right lines have vacuum in 2wd and 4wd by pulling off the connector at the shift motor. Cover the vacuum line for a few seconds with your finger, you will feel/hear the vacuum when you take your finger away. If the switch has vacuum (red line at the switch), and you are getting vacuum at the shift motor on the green line in 2wd and the white (or yellow) line in 4wd, then the switch is working as it should, and the problem is in the axle shift assembly. Pull the shift motor off (4 bolts), and have someone shift the t-case while you watch and see if the fork moves. Don't get run over doing this, the engine has to be running..... If the fork will go one way but not the other, and you have good vacuum supply on both 2wd and 4wd lines, then the shift motor is not working right. First clean up the parts, check for free movement of the fork. If it still doesn't work, get a new/used one or convert to a cable system. If it does work off the axle, then check the sleeve that the fork moves that hitches the two axle halves together- its isn't moving freely. There is a Canadian shift conversion kit, if you want to avoid border hassles. Sorry I don't have the name.
 
Thanks 4xBob

But the next Question i have is my 4wheel drive Acuator has both yellow and white that go into the Acuator? Is that right? And if so how do i hook them up?


Tom
 
There is a $10 vacuum harness that goes to the actuator, two lines i believe that runs right down the frame rail to the actuator. Mine would not go in to 4wd, replaced it cause the line was collapsing when vacuum applied, works fine now. I am looking into the Posilok thing, but not for awhile yet down the road.

Cory
 
On a 1990 vacuum disconnect motor there are two connections on the side of the pancake body which are white (or yellow) and blue, and the single line to the outside end is green. If you have only two lines, then one will go to the side of the pancake body, and one to the end. To figure out which is which, start the engine for vacuum supply, and see which line has vacuum with the t-case shifter in 2wd. Connect that line to the end connection, and the other line to the side connector. If this is backwards, then you will engage the axle in 2wd, and disengage it in 4wd, so there will be no 4wd. You should have a third line for the vacuum actuated switch which turns on the 4wd dash light- this is how it works for 1990 and 1985 disconnect axles used with a 231 (CommandTrac) for 1990, (228? 229? for 1985....not SelecTrac either year) transfer case, I would be surprised if the 1989 didn't use the same setup. How many connection nipples (straight metal pipes) are there on your shift motor?
 
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I was reading your post about the vacuum pod problem ,i have made a peice to replace the pod and holds the slip collar in place ,NO more vacuum problems.
frank
 
Thanks for the help guys!!

I figured out my problem today.. The guy who had my Xj before me must have mixed up the lines because the switch was not hooked up also.. so i fixed that and replace the lines with new rubber ones.. And no more problem...

Thanks agian....

Tom
 
I'm trying to find out how to do the cable adaption. Cant seem to find anything which shows HOW to do that. Can anyone help guide me to something which shows How?
 
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