TH400 kick down adjustment
Thread Starter
Instructor
Joined: Apr 2004
Posts: 106
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From: Norfolk VA
TH400 kick down adjustment
Ok, I have adjusted the kickdown cable on a TH350, but don't see one on the TH400. What is the procedure for adjusting the kickdown? When I nail it, the secondaries open, but it won't kick down.
Thanks!
Todd
Thanks!
Todd
The ORIGINAL and bestest
Joined: Oct 2000
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From: Toronto Ontario
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The TH-400 doesn't have a cable for kick down, instead there is an electrical switch activated by the gas peddle. You can adjust it by pulling the switch out all the way and then putting the gas peddle to the floor "setting" the kick down position. To test if it is set right, turn the ignition on without starting the engine, and press the gas to the floor, you should hear a "click" from the tranny.
Burning Brakes
Joined: Feb 2004
Posts: 958
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From: In the Beautiful Shenandoah Valley of VA
The kickdown on a Turbo 400 is controlled electrically by a switch on the gas pedal. There isn't much adjustment, so you likely have an inactive electrical circuit that needs to be diagnosed.
Steve
:edit:
Same time posts!
Steve
:edit:
Same time posts!
Thread Starter
Instructor
Joined: Apr 2004
Posts: 106
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From: Norfolk VA
Originally Posted by Sarge81
'68-'72 THM-400 Detent switch is located on the carburetor.
'73-'77 THM-400 " " " " over the accelerator.
Just a little FYI on the differences.
'73-'77 THM-400 " " " " over the accelerator.
Just a little FYI on the differences.
Where on the carb? Mine's a ' 72 and the only thing I can see is the TCS solenoid. Am I looking in the wrong place?
Thread Starter
Instructor
Joined: Apr 2004
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From: Norfolk VA
Originally Posted by 7t2vette
The switch is on the gas peddle on a 72, the years are wrong on the other post.
Thanks for the straight skinny. Tomorrow I will adjust as described and post results on Tuesday.
Todd
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Instructor
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From: Rittman oh
I have a 69 L-68 W/ Th400 and the detent switch is above the gas pedal. To adjust it there is a small hole in the right side of the switch that is actuated by the pedal. Depress the pedal fully and move the switch on it's mounting bracket until the holes line up between the plunger and the housing and the switch. You need to insert a small pin, I used a long allen wrench, to check allignment. I have exact instructions somewhere, I'll keep looking.... Also, there is a vaccum line that comes off the intake that supplies power to the servo (I think). Make sure the vaccum line is intact as well. When I did mine I used a test light at the pedal switch and the had a helper mash the pedal while I tested it at the transmission ( with the ignition on and engine off of course ) I'll see if I can find the manual, my memory fails me at times. Swamper
Instructor
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From: Hilton Va
I have a 69. It's kickdown switch is above the gas pedal. I could not find a switch for mine at any of the vendors or trans. shops. What I finally done was to go to NAPA and had them to order a switch for a Subaru (I think an 82-85) or something like that, It is a pushbutton type. It mounts on the carb. I make a bracket and attatched it to it and ran the wires from the original switch wires to the new switch, and it works like a charm. You may be able to find one for your model, but in case you can't, I just thought I let you know of another way to go.
Thread Starter
Instructor
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From: Norfolk VA
Originally Posted by carhound
I have a 69. It's kickdown switch is above the gas pedal. I could not find a switch for mine at any of the vendors or trans. shops. What I finally done was to go to NAPA and had them to order a switch for a Subaru (I think an 82-85) or something like that, It is a pushbutton type. It mounts on the carb. I make a bracket and attatched it to it and ran the wires from the original switch wires to the new switch, and it works like a charm. You may be able to find one for your model, but in case you can't, I just thought I let you know of another way to go.
Thanks for the alternative. If the original switch is dead, that will be good to know!
Todd
Drifting
Joined: Jul 2012
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From: Slovenia, EU
2017 C3 of Year Finalist
My 71 also has electrical switch at the gas pedal assembly!
I noticed it when I changed the throttle cable and guess what, I also have a problem with kickdown when I floor it!
I will try the adjustments as well and report back!
https://willcoxcorvette.com/corvette...ownshift-70-77
I noticed it when I changed the throttle cable and guess what, I also have a problem with kickdown when I floor it!
I will try the adjustments as well and report back!
https://willcoxcorvette.com/corvette...ownshift-70-77
Last edited by Primoz; Jun 17, 2017 at 03:28 AM.
Drifting
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From: Schaumburg IL
Jim
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Melting Slicks
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From: Russell Ontario
St. Jude Donor '09
Primo , have a look at the wiring under the car left side of tranny , mine was all burnt, I repaired the 2 wires and tested the switch on the pedal and it clicked , test drove the car and it works , I did the adjustment on the pedal with my fingers to see if it moved ok . 
