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Unread 04-27-2013, 12:24 PM   #1
CJ7fanQTnot
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1980 TH 400 kickdown help needed

1980 CJ7 with GM350 to "JM"TH400 quadra trac AWD. Tranny shifts early and does not down shift. I am putting it back together after a body off restore. The kick down seems to be wired into the borg warner TC instead of the driver side of the tranny.

I am considering running a new wire direct to tranny but not sure how to handle the wire to the TC.

Also I have 2 mystery wires at the bulk head connection. one is thin and black that is about 4 feet long and the other is a rosy orange with a white stripe and heavier gauge, it looks like I clipped it short and can't remember why or where it goes.

This project has gone on far to long and I only have myself to blame. And also money, ha.

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Unread 04-27-2013, 06:55 PM   #2
rjbruzan
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Turbo 400 is an electric kickdown from a small box on the carb linkage. So follow the wires. If not running it the shift point have some adjustment in the vacuum modulator. A tiny screwdriver inside the vacuum port give some adjustment.

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Unread 04-27-2013, 09:35 PM   #3
cruiser54
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Actually, there is a kickdown switch up near the accelerator linkage in the cabin. The rod from the carb to trans is for trans line pressure, to increase it under heavier acceleration. The vacuum modulator tells the trans when to upshift according to engine vacuum/load. Adjustable versions are available.
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Unread 04-28-2013, 08:19 AM   #4
rjbruzan
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On a 400 there is no linkage like a 727. Shifting is by vacuum.
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Unread 04-28-2013, 08:30 AM   #5
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Quote:
Originally Posted by rjbruzan View Post
On a 400 there is no linkage like a 727. Shifting is by vacuum.
Correct. Upshifting is by vacuum, Kickdown is by the pedal switch. Line pressure is done by the rod from the carb to trans.
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Unread 04-29-2013, 01:08 PM   #6
CJ7fanQTnot
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the kickdown switch is on the gas pedal assembly and was originally wired to the passenger side of the Borg Warner transfer case. I know it should go to the kick down solenoid and will wire it there. There is a white pigtale wire on the transfer case that I don't know what to wire to now.

Kick down was attached to the Emergency indicator switch ( white wire next to white ground), I have no idea why. I will wire that to my light on my switch I guess, it is electronic driving a vaccum actuator.
emergency-switch.jpg  

Last edited by CJ7fanQTnot; 04-29-2013 at 07:05 PM.. Reason: add image
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Unread 04-29-2013, 07:24 PM   #7
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Look coming out of the square block on the firewall where the main wiring block plugs into.
There will be a yellow and an orange wire that lead to a small double plug (actually 2 singles hooked together) about 8" away from the main wiring block.

The Yellow leads down to your kickdown on the driver's side of the transmission. It is a direct wire from the plug to the transmission. Basically a direct line from power, to the kickdown switch, to the transmission.

The orange leads down to the transfer case. It will plug in on the passenger's side of the case(beside the speedometer cable), and just lights up the light on the speedometer when it's in "emergency drive". Basically a direct wire from the switch in the transfer case, to the light bulb in the speedometer.

At the gas pedal, check for power coming into the the switch, it should have power. Trip the switch with your finger, you should then have power coming out of it. Check for power at the transmission plug. My wire was melted in half by the exhaust. The coating looked fine though.

The early shifting is probably a problem with your vacuum actuator. We can cover that after you get the kickdown switch taken care of.
I've been through the same thing with mine. Got it shifting like a champ now.
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Unread 04-29-2013, 07:35 PM   #8
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Here's a handy wiring diagram for you. Save it (so you can zoom in more), print it, laminate it, and even sit at night and study it (good bathroom reading material). I have one and am always using it for something or another.
The transfer case and transmission are the two circles in the bottom left of the diagram.

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Unread 04-29-2013, 08:11 PM   #9
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This is how it sits now. The vin plate says an 1980 with 304 but it has borgW and quadra and I find that wasnt in 1980 CJ7. It also has a chevy 350 with a conversion plate for the "jm" th400. So, I think I signed up for someone elses wiring brainstorm.

It ran when I started project but shifting poorly as described before. The kickdown is not wired back through the bulkhead connection but to passenger side to go back to Transfer.

I think I am just going to bring it out to tranny with oil pressure line in grommet.

I still wonder about that red/ white wire in pic.

I will study diagram more and see what is still there.
Thanks for your help.
palm-pre-4-2013-030.jpg   palm-pre-4-2013-032.jpg   palm-pre-4-2013-149.jpg  
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Unread 04-29-2013, 08:26 PM   #10
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Yeah, the trans and tranny shouldn't be wired together. I do know what you're going through. I bough one with a 'glass body, and had to deal with the wiring mess that came along with it.
My PO painted it all blue.....along with all of the wires. Every single wire....BLUE.
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Unread 04-29-2013, 09:35 PM   #11
CJ7fanQTnot
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I feel your pain of the "All these F'in wires are blue!"

I have yet to get the battery back on because I think I lost the bag holding the bolts to the bracket mounting and also a few other random other "missing pieces" but working backwards I found that the PO was fond of self tapping screws... yay him.

I think I have to look at this now component to component not a jeep as a whole.

If you know what the red and white wire is though give me a clue please. and also the small guage black wire that goes to the passanger side in the lower left, right when looking to front.

Last edited by CJ7fanQTnot; 04-29-2013 at 09:41 PM.. Reason: to clarify
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Unread 04-30-2013, 07:30 PM   #12
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Sometimes it's easier to rip out all the wires and start laying in new, one at a time. That's the process I used in my CJ 2A
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