TCase '76 CJ7 Quadra Trac vacuum line question

[JohnEJo]

Hello. I have recently acquired a '76 CJ7 with the quadra trac system. It is currently stuck with the e-drive engaged. I have turned the e-drive switch (in the glove box) back and forth to try and get it to disengage, and I have even tried multiple times doing a bunch of figure 8's, but all to no avail. I checked the vacuum lines and noticed a couple tares where they connect and cut those ends off and reconnected, but again to no avail. Since it has sat for nearly 10 years, and possibly much longer than that, I am wondering if I need to just replace the lines. I have not been able to locate replacement metal lines anywhere, and while I have heard of some just using rubber lines instead of metal I have been unable to identify what size tubing I need. Does anyone know what size tubing I will need to get for this?

Thank you.

 

[gert]

we have a member here 007 he has quadratrac on his Jeep Im sure he would know as he has had to do a bunch of work to his system over the years

 

[007]

Hello. I have recently acquired a '76 CJ7 with the quadra trac system. It is currently stuck with the e-drive engaged. I have turned the e-drive switch (in the glove box) back and forth to try and get it to disengage, and I have even tried multiple times doing a bunch of figure 8's, but all to no avail. I checked the vacuum lines and noticed a couple tares where they connect and cut those ends off and reconnected, but again to no avail. Since it has sat for nearly 10 years, and possibly much longer than that, I am wondering if I need to just replace the lines. I have not been able to locate replacement metal lines anywhere, and while I have heard of some just using rubber lines instead of metal I have been unable to identify what size tubing I need. Does anyone know what size tubing I will need to get for this?

Thank you.

It sounds as though you may have more than one problem, but that doesn’t necessarily mean that either one of them is especially bad.

If you don’t have vacuum, then the the actuator won’t work in either direction. And if you do have vacuum and it doesn’t work, then that either means the diaphragm is bad or the fork is a bind.

If I remember correctly, the steel lines, connect to rubber lines, just short of the diaphragm. And yes, you can absolutely use rubber lines, but I would suggest using fuel lines because they handle the gas vapor and are less likely to collapse.

Pull off whatever is left from the diaphragm, and figure out what size that you need, if I remember correctly, they might be as small as 3/16 get yourself some good line, and get yourself at least one cap.

The best way to test this laying on the ground with a brake bleeder kit, using that to apply vacuum, and thus actuate the shifter.

If you find that vacuum, is your only issue, then it’s easy enough to fix. If you find that the diaphragm is shot, then I think BJ’s off-road sells them. If not eBay.

If you find that it needs replaced, or if you determine that the fork is in a bind, there are two bolts that secure the plate on top of the transfer case. If you carefully remove those and the plate, you can move the fork along the shaft with your hand. Again, be careful removing those because if you drop anything in the transfer case, then that will certainly change the scope of your work. ;-(

 

[CJ]

I called 007, that is what we do to help.
007 to the rescue!

 

[JohnEJo]

It sounds as though you may have more than one problem, but that doesn’t necessarily mean that either one of them is especially bad.

If you don’t have vacuum, then the the actuator won’t work in either direction. And if you do have vacuum and it doesn’t work, then that either means the diaphragm is bad or the fork is a bind.

If I remember correctly, the steel lines, connect to rubber lines, just short of the diaphragm. And yes, you can absolutely use rubber lines, but I would suggest using fuel lines because they handle the gas vapor and are less likely to collapse.

Pull off whatever is left from the diaphragm, and figure out what size that you need, if I remember correctly, they might be as small as 3/16 get yourself some good line, and get yourself at least one cap.

The best way to test this laying on the ground with a brake bleeder kit, using that to apply vacuum, and thus actuate the shifter.

If you find that vacuum, is your only issue, then it’s easy enough to fix. If you find that the diaphragm is shot, then I think BJ’s off-road sells them. If not eBay.

If you find that it needs replaced, or if you determine that the fork is in a bind, there are two bolts that secure the plate on top of the transfer case. If you carefully remove those and the plate, you can move the fork along the shaft with your hand. Again, be careful removing those because if you drop anything in the transfer case, then that will certainly change the scope of your work. ;-(

Awesome! Thank you! Hopefully it will be something simple like vacuum lines being the culprit.