In the 83 wagon the dash switch will not activate the 4X4. I have locked the front axle so don't need vac to it. I want to simplify the vac system as per Gronk's method. It shows a single line from the switch to the shift motor. However, the switch, and also a switch I have from a non-disconnect axle, have 3 ports for vac hoses. Which one would I connect to, and what do I do with the other 2?
I'll need to dig through the notes on this one. Might take a couple of days.
You should be able to either blow through the port ( yes with your mouth and a small length of hose ) or apply vaccumm , and see wich line the switch will pass it through when it's moved left or right...... and I would assume connect it to that one... ?? sounds simple heh. : )
Quote from: 68AMXGOPAC on October 23, 2011, 06:49:56 PM
You should be able to either blow through the port ( yes with your mouth and a small length of hose ) or apply vaccumm , and see wich line the switch will pass it through when it's moved left or right...... and I would assume connect it to that one... ?? sounds simple heh. : )
Exactly. You have a supply port, a 2wd port, and a4wd port. The actuator on the t-case requires vac both directions to hold the selected range. The blow method works just fine for figuring it out.
I've done this a number of times on FSJs and I'm about to do it on my Eagle wagon before I put the 727 in (decided to wait till spring for the AW4 conversion so I'll have 4wheel drive this winter)
Vacuum comes from the motor to the vacuum ball first (so you have a reservoir with a check valve) Then it goes to the dash switch through the red line.
The dash switch has 2 lines out and you need both if you want to be able to switch between 2 and 4 wd. With the front diff locked and out of the equation, you can remove (I almost said rip. :rotfl: ) those lines so you have only 2 going to the tcase motor.
Make sure the tcase motor is functional. I take it off and see if it moves back and forth or it's rusted up inside. (if rusted too much, I replace it with one for an '88 to '91 Grand Wagoneer because it only has the 2 ports you need already) Lubricate it AFTER ensuring the diaphragm isn't shot. Use something that won't eat the rubber or you'll be right back in to do this again soon.
Here's the direct link to vacuum diagrams, thanks to Tom "Ol Jeep" Collins
These are for the FSJ, but the system is the same
http://oljeep.com/gw/vac/axle/83-84-FSJ-FrontAxle2-whl.jpg
http://oljeep.com/gw/vac/axle/83-84-FSJ-FrontAxle4-whl.jpg
This is what the parts look like in real life:
http://oljeep.com/gw/vac/axle/83-84-FSJ-FrontAxlePictorial.jpg
Here's the Eagle vacuum axle/tcase diagram for comparison (PDF download only)
http://oljeep.com/gw/vac/eagle/EagVac.pdf
Back to the hook up: In the diagram below
http://oljeep.com/gw/vac/axle/83-84-FSJ-FrontAxle2-whl.jpg
at the bottom right of center is the tcase shift motor.
Without the front axle rubbish, the "front axle connecting port" needs to be blocked off. I use silicone sealer and a vacuum cap with a hose clamp to ensure it stays.
Then the check valve delay isn't needed or the lines to the front axle connecting port.
Everything on the bottom left corner can be removed and the lines reconnected like this:
Green line from dash mounted mode selector vacuum switch to the rear port on the tcase motor (remove the line to the delay valve from the system so you go direct)
Yellow line from the dash mounted mode selector vacuum switch is re-routed directly to the front port of the tcase shift motor.
*NOTE* If your front axle is NOT permanently engaged, shifting into 4x4 without it being locked will result in catastrophic tcase failure if you have a NP119, NP129, NP128 (although that one takes longer), or a swapped in NP219, NP229, NP228 (takes awhile, like the NP128 because it doesn't have a viscous coupler, but excessive revving will blow up the tiny differential in it)
If you have a NP208, it has no viscous coupler but it doesn't play well in good traction areas in 4wd. The suspension winds up, making it hard to steer and actually twists VERY hard on ujoints, etc. On dirt, snow, etc, it's awesome.
Thank you very much for all that information. I'll sort through it when I have more time.
However, my mode switch has 3 ports.
This is the 83, stop to shift but I did lock the front axle with the hose clamp method.
You can remove that pull down thingy and have shift on the fly since your front axle is clamped.
Quote from: jim on October 24, 2011, 01:12:42 PM
Thank you very much for all that information. I'll sort through it when I have more time.
However, my mode switch has 3 ports.
This is the 83, stop to shift but I did lock the front axle with the hose clamp method.
All the diagrams I posted have a 3 port dash switch.
Carnuck, I wasn't feeling well last night didn't stay up to research the info. I hope to be able to do that tonight. That's good to know about the switch.
I had thought about removing the pull down knob but wasn't sure how to do it.
I have a switch from a non-disconnect Eagle but it's the wrong color. I may paint it and try to get the resident in-house artest to paint the lettering.
I'd lock up the front axle first. There is a C clip holding that pin and spring in. Pull the clip and reinstall the switch. Piece of cake!
Front axle has been locked in for almost a year. I'll look at that switch. It would easier to pull a clip than repaint.
I finally got a chance to look over this info somewhat. I still need to spend more time with it, but I'm beginning to get a pretty good idea about all of it.
I do have a question about this:
"Vacuum comes from the motor to the vacuum ball first (so you have a reservoir with a check valve) Then it goes to the dash switch through the red line."
Would it be feasible to come directly from manifold vacuum to the switch? I'm concerned about losing something else if I remove a hose from the vac can to connect the switch to it. I already have a tee with one side plugged at manifold vac. If you say it is necessary to use the vac can I can probably find a way to tee into it. I think the yahoo that installed the motor plugged it.
The vacuum can was stock for the 4x4 system. There should be 2 in your car. One for heater/ac and one for 4x4. Ball shaped usually. Jeeps use a football shaped one behind the front bumper.
My heater/ac vac connects to the ball shaped can on the driver side fender. There is another on the passenger side firewall for cruise and other stuff. I'm not where I can look at this time but at least one and maybe both Eagles have a vac anc inside the drive side wheel well. I have seen the vac lines running through the inside fender.
Is it necessary to use the vacuum cannister or is it feasible to run directly from manifold vac to the switch?
Quote from: jim on October 27, 2011, 01:28:20 PM
Is it necessary to use the vacuum cannister or is it feasible to run directly from manifold vac to the switch?
I believe the purpose of the ball is to have a vacuum reserve, for low vacuum conditions. Without the ball, you would lose vacuum to the transfer case vacuum motor, and with no vacuum on either side of the diaphragm, I bet it might be able to go into false neutral. You sure wouldn't want that to happen when merging onto a highway.
I don't think AMC would have put it in there if it wasn't necessary (and they didn't even think a metal valve cover was necessary).
Jim, I have set these up several ways with great success. 90% of the time, I eliminate the vacuuum ball and all the "stuff" attached and go direct with the RED source line to manifold vacuum on the intake.
I have never had an issue doing it this way on Jeeps or on Eagles. When the engine is running, there is vacuum. Which ever way your selector switch is positioned, will be the way it works.
I started doing it this way when time after time I was troubleshooting Jeeps and Eagles that had bad, missing, weak/cracked otr otherwise inoperable vac systems.
This method has always worked and worked well for me.
My understanding is the vac res is there for the 4x4 system to give you up to 2 shifts when the vehicle is not running. It actually will work if you vac system is stock and working, you can select 2x4-4x4 a few times before the vac wears out w/ the engine not running.
With pulling direct manifold vac to the switch, you will only be able to switch if the engine is running.
My $.02
Actually, it's so you have vacuum when climbing a hill or high torque situations (like pulling a trailer up a grade) so the front axle and tcase don't un-shift on you (happened to me and took out a NP229 in an FSJ)
It wooorrrrkkked!! I no longer have to crawl underneath my Eagle with a 9/16" wrench to shift into 4X4. I employed a little redneck engineering but it worked! I couldn't make the yellow hose from the switch reach the shift motor so I left the red hose on it and spliced the yellow into it.
It works!
I was actually surprised when I got to my off road test track (a leaf covered area near my driveway ;)) and it shifted both ways several times.
I still have to replace the skid plate, remove the pull down knob from the switch and put a cable tie on some hoses to make it all look a little neater.
This is the last major chore before looking into dent and rust repair and paint. The passenger side doors that I scored at the meet don't match. It provides a little incentive to get the painting done. I need to get some things done to the 88 first so I can drive it while having the 83 painted. Of course I can and do drive the 88 as is but I want to upgrade some things.
I could have done all that today but if I wanted some chili I had to prepare Bambi for the pot. I may be able to get those chores done the first evening or two next week.
What next? This is somewhat embarrassing, but if someone has a good way to put the mode switch back in the dash, please drop by Arkansas and demonstrate it.
Otherwise pictures and/or suggestions would be appreciated.
I haven't been able to find diagrams in the TSM. It should be simple enough but I can't get the screws to tighten all the way when it's in the position it looks like it should be in.
The skid plate went back on easily. I've learned how to do that. I put on a couple of cable ties to keep the vac hoses away from the starter. Then removed the pull down knob from the switch, which was easy once I knew what to look for, thanks to help from the forum. Then I got stuck with that *&^%@#$$%^ switch!
Haha I've done that several dozen times and its still really hard. It usually takes three or four attempts to work right. The clip has an incredible desire to pop out of place. There is essentially a stepped piece of metal with two screws that has to have the upper and lower edge against the top and bottom steel rails.
I suggest finding two screws that are longer than the original ones but have the same thread size. Then loosen them all the way so that only a few threads are coming out the back of the metal bracket. Then put the metal bracket into position while pulling the plastic face away from the dash. I accomplish this with my left hand reaching up and behind the dash while my right hand pulls at the front face. You need to keep one hand pulling gently at the front face the entire time as you tighten the two screws or the backplate will hop out of position.
The backplate must engage the metal reinforcement behind the external plastic. It might help to position that and see how the steps in its shape fit the dash before you attempt it with the front face blocking your view.
I could see that the bottom of the metal bracket fits behind the double channel, but I wasn't sure how to position the top. From what you're saying the top goes behind a metal channel, also. I knew that was the most logical place for it. So far I haven't been able to get my hand behind the dash. I tried so many times and ways that I ran down the battery on my little screwdriver and got a larger drill/driver.
The best thing you can do is try to position the bracket by itself to visualize where it is supposed to be. I've had it upside down before, and couldn't tell for the longest time. You have to keep pressure pulling it toward you or it will just fall out of place.
I have the package tray out in most of my Eagles. With that tray in place you're never going to be able to reach up underneath. In that case I push the screws out with both thumbs while both hands hold the front face, that keeps the bracket straight behind the face while I feel around until its in place.
I've never used an electric screwdriver for this. That just sounds bulky and cumbersome. The screws need to be tightened together, so I just do a half turn or a single turn on the left, then a turn on the right, then back to the left. You have to keep that front face pulled straight out the whole time as you tighten them.
I have a very strict personal rule about power tools. I never tighten a faster in plastic with a power tool. I will run one up if it is very long, and I will remove screws, especially if I have done it over and over again.
I pulled the package tray and I still can't get my hand behind the bracket location.
I think I've tried all the methods suggested here without success except for longer screws. I'll try to find some after work tomorrow.