command trac engine vacume line?

1991 cherokee laredo, 4.0, 4x4, dana 30 front, dana 35 rear.

vacume lines were carelessly removed from firewall one day...
ta da... and the next day my front axle wont engage...

just wondering wich one needs to be hooked up to vacume to engage the command trac system?

all the lines from the transfer case to the axle are intact and in place.

shouldnt there be a vacume line from the engine bay to the tranfer case?

every diagram ive seen just has a line labled "engine" and thats as discriptive as it gets.

looking to see if someone could post a pic/link of the engine bay and the vacume line connections needed to engage the front axle....

thanks alot.

the vacuum line comes from the canister in the bumper. Travels from there up passenger side of engine bay behind the battery. it then goes to the tranfer case switch to activate the actuator on the axle. The line from the canister (behind the battery) usually breaks over time. When i was having trouble engaging 4 wheel on my 91 laredo, i replaced this line and voila! I had 4wheel and it solved my cruise control problem amongst others. hope this helps

that helped and thanks... but...

so where is the source of the vacume?

from what i remember about the canister it had one line... so where would the vacume come from?

if that line were still there did it have a t fitting mid way through it? routing one line to transfer case, one back to the manifold supplying the system its vacume and one to the canister?

There should be a vacuum line from the manifold, runs along the firewall, has a one-way check valve in it, then a "T", one line runs to the vacuum reservoir in the bumper, another to the transfer case switch. There should be one line running from the vacuum motor on the axle back up to the firewall to a vacuum/electrical switch for the 4x4 light. Two line run from the transfer case switch to the vacuum motor on the axle--engage and disengage.

There is also a line off the main line for the cruise/HVAC.

thats what im lookin for right there...

thanks alot...

plann on doin the cable conversion but $$$ is very low...

like everything else i own, it will unfortunately get some kind hillbilly conversion so i can just manually engage the pos.

onmyway said:

thats what im lookin for right there...

thanks alot...

plann on doin the cable conversion but $$$ is very low...

like everything else i own, it will unfortunately get some kind hillbilly conversion so i can just manually engage the pos.

Click to expand...

Number of options from JP Magazine: http://www.jpmagazine.com/techartic...154_0904_dana_30_vacume_disconnect/index.html

Adding to above: among the lines from the TC switch, you'll find one, blue I think, which has a little filter on the end, and is not connected. It's the vent line and should be that way.