Calgary Jeep Association

4x4 Related Groups => Tech Talk => Topic started by: EVOLUTION on November 22, 2005, 02:34:23 PM

Title: 4wd not engaging
Post by: EVOLUTION on November 22, 2005, 02:34:23 PM
Hey there! I bought an 87 Comanche (4.0L, auto) and the 4WD doesn't work. When I put it into 4H or 4L the driveshaft doesn't turn or anything.

Any ideas of what it could be? Maybe my t-case is screwed?

Thanks!
Title: 4wd not engaging
Post by: gsxtacy on November 22, 2005, 03:20:36 PM
lock in the hubs...
Title: 4wd not engaging
Post by: EVOLUTION on November 22, 2005, 03:28:57 PM
Doesn't have hubs.
Title: 4wd not engaging
Post by: apex on November 22, 2005, 03:35:13 PM
check the linkage between the shifter and t-case. something might've disco'ed.
Title: 4wd not engaging
Post by: EVOLUTION on November 22, 2005, 04:16:01 PM
linkage is fine too.
Title: 4wd not engaging
Post by: gsxtacy on November 22, 2005, 04:34:41 PM
oops, maybe there's something broken inside it?
Title: 4wd not engaging
Post by: Gearhead on November 22, 2005, 11:13:03 PM
Sounds expensive.
Title: 4wd not engaging
Post by: RedYJ on November 23, 2005, 12:20:17 AM
Maybe a wire to the vaccume thingy on the axle is gone and not working and not engaging the hubs?  If thats not it then this could be an expensive problem where your Tcase has some missing parts or gear teeth, or maybe everything is missing??
Title: 4wd not engaging
Post by: Becker on November 23, 2005, 11:34:59 AM
i'm not sure if the commanche set up is the same as it is on the YJ, but I had similar problems this past year.  Sounds like it could be a vacuum problem.

On the top of the t-case there is a plug with vacuum lines coming out of it.  One of the lines comes from a vacuum line under the hood, and the other 2 lines go to the shift motor located on the front diff.  I had nightmares with mine this past summer as some of you can attest to, and eventually after many attempts to repair, ended up removing the shift motor and replacing it with a non vacuum reliant manual set up.

It was the best money i ever spent, well maybe not the best, but it did solve one of the problems.  

Just my 2 cents
Title: 4wd not engaging
Post by: Bnine on November 23, 2005, 12:53:46 PM
If the driveshaft doesnt turn, the problem is before the vac actuated axles. T-case engagement to the driveshaft is mechanical.

Either a linkage issue, probably inside if you cant see anything obvious outside, a shift fork problem, or something more serious like a broken chain.

The chain is extremely unlikely. One they dont really break to often, and two, if it did it would likely wrap up and blow the case apart.

Thats my guess, then again I dont deal with any of those vacum systems on a regular basis.
Title: 4wd not engaging
Post by: EVOLUTION on November 23, 2005, 01:24:17 PM
Hey thanks for all the tips guys!  I'm going to go through a more thorough investigation this weekend while consuming an exhuberant amount of beer.  Oh and I'm going to do this in SPOT's garage, but he doesn't know it yet...   :lol:

Being a girl DOES have it's advantages after all...   :wink:
Title: 4wd not engaging
Post by: Spinalguy on November 23, 2005, 02:47:39 PM
Quote from: "fragz"
Hey thanks for all the tips guys!  I'm going to go through a more thorough investigation this weekend while consuming an exhuberant amount of beer.  Oh and I'm going to do this in SPOT's garage, but he doesn't know it yet...   :lol:

Being a girl DOES have it's advantages after all...   :wink:


And luckily my girls jeep is already inside Spots garage getting a new engine put in, so yours may be cold and lonely sitting outside :wink:  :D
Title: 4wd not engaging
Post by: EVOLUTION on November 23, 2005, 03:20:23 PM
Quote from: "Spinalguy"
And luckily my girls jeep is already inside Spots garage getting a new engine put in, so yours may be cold and lonely sitting outside :wink:  :D
Yes you are correct...  :cry:  :cry:
Title: 4wd not engaging
Post by: Spinalguy on November 23, 2005, 04:15:48 PM
But i am sure your will be done before the snow flies.....  :)
Title: 4wd not engaging
Post by: Luxton on November 24, 2005, 04:39:25 PM
Quote from: "Gearhead"
Sounds expensive.


aren't all jeep problems expensive?  :D
Title: 4wd not engaging
Post by: SPOT on December 07, 2005, 04:45:43 PM
baaaa I fixed it.Cheap and easy.
Title: 4wd not engaging
Post by: Luxton on December 07, 2005, 04:49:37 PM
how?

what was the problem?
Title: 4wd not engaging
Post by: SPOT on December 07, 2005, 05:11:07 PM
the same as all problems on jeep's the vacume system.and shitty connections.I have fixed 3 jeeps this week the first the shift fork in the VDA was broken,some one tried to shift on the fly at to high of speed and broke the fork.Erins was leaking oil and expanded the plug and it fell off clean it up and a litte silicon good as new.The heaters blowing cold air is the connection on the top of the heater assembly in behind the radio.is it either fell off.is jamed open with junk or the vacume  pot is bad in is holding the door open or closed.