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-   -   TH400 elec kickdown switch on pedal (https://67-72chevytrucks.com/vboard/showthread.php?t=660593)

c10454 02-17-2015 08:15 PM

TH400 elec kickdown switch on pedal
 
1 Attachment(s)
The switch in the picture has a return spring, my question is does the throttle pedal rod have to move the switch all the way to the stop or just move it enough to 'break' the circuit? Best way I can describe it as a sliding momentary switch. When my pedal is at WOT it moves the slide about 50% of its travel.

Thanks

Slammed84 02-17-2015 10:12 PM

Re: TH400 elec kickdown switch on pedal
 
I wish I could comment but I don't know. I know I need one though. I think I would rather have the switch that you mount on the throttle bracket.
I would assume that you should be able to adjust your switch to allow for earlier or later kickdown.

Have you had it installed yet? How far does the switch have to be pressed to actually downshift?

Slammed84 02-17-2015 10:14 PM

Re: TH400 elec kickdown switch on pedal
 
You might be able to do some testing with a multi meter and figure out the point it switches and sends the signal to the trans. Might need an extra set of hands though

c10454 02-17-2015 10:36 PM

Re: TH400 elec kickdown switch on pedal
 
I currently have this installed on my truck, 1976 c10. I used this picture because it was much clearer.
Thats what I was thinking but not sure if it has to be pushed slightly or moved to its stop to trigger...
Too much salt on the roads up here for a road test :(
I have been fighting some weird shifting issues, yea I might have to break out the multi meter to figure out how this circuit works.
Thanks for the reply Slammed

Slammed84 02-17-2015 10:47 PM

Re: TH400 elec kickdown switch on pedal
 
Two wires right? Should be simple to just unplug the harness and set a meter for continuity. Hold the leads on the spades and slowly push that plunger in til it beeps.
This is definitely on my list of stuff to do for my truck. I had gotten do used to manually downshifting though, it will be weird if it actually shifts correctly.
I stole my 400 out of a C20 longbed, not sure the year. Had no idea about the electric kickdown so didn't take it with the trans.
But I like the B&M style throttle setup for them, have you seen those?

c10454 02-18-2015 07:16 PM

Re: TH400 elec kickdown switch on pedal
 
Thanks for the tip. With 3.73 gears I dont need it to often.
I have not seen the B&M style, got a link or pic? I'll have to check it out

Slammed84 02-18-2015 07:36 PM

Re: TH400 elec kickdown switch on pedal
 
http://www.bmracing.com/products/202...-transmission/

Heres the URL

gmachinz 02-18-2015 08:03 PM

Re: TH400 elec kickdown switch on pedal
 
I have a good and tested TH400 carb mounted kickdown switch if you want one. PM if interested-its my last one so if ya want it....$45 shipped takes it. Its from a 69 C20 pickup originally.

chengny 02-19-2015 06:39 AM

Re: TH400 elec kickdown switch on pedal
 
That switch (detent switch) is self-adjusting. Procedure to reset the point at which the contacts close (and energize the detent solenoid):

1. Remove the switch from the bracket and unplug the connector

2. Locate the spring tab (on the end of the slide closest to the driver)

3. Depress the tab and push the plunger all the way in (towards the firewall)

4. Remount and reconnect the switch

5. Push the gas pedal to the floor (the switch will make a ratcheting sound)

6. That's it - the switch is adjusted.

http://s5d2.turboimagehost.com/t1/22...nSpringTab.jpghttp://s5d2.turboimagehost.com/t1/22...alPosition.jpg

From the service manual:

http://s5d2.turboimagehost.com/t1/22342810_detswadj.jpg

c10454 02-19-2015 06:11 PM

Re: TH400 elec kickdown switch on pedal
 
Sweet CHENGNY, thats a great help. Thanks everyone who chimed in. Now if April would get here I can do a road test! Its been in the single digits here lately.

Slammed84 02-19-2015 10:57 PM

Re: TH400 elec kickdown switch on pedal
 
Quote:

Originally Posted by c10454 (Post 7056646)
Sweet CHENGNY, thats a great help. Thanks everyone who chimed in. Now if April would get here I can do a road test! Its been in the single digits here lately.

Hell im about 800 miles south and its not much better here. was 22 this morning wind chill was 9, bbbbrrrrrrr


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