Stiff pedal with kickdown hooked up. Help please!

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Dusterdude72

Dusterdude72

IN MOPAR MUSCLE MAGAZINE
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Hey guys, I ran into this issue a couple months back but put it on the back burner until I was closer to having the car on the road. its a 72 duster,small block, 904 trans,transgo tf2 shift kit ( I did not use the parts to make it full manual ...just the shift kit). I have a stainless braided throttle cable (new and adjusted in), the bracket that holds both it and the kick down cable. And I have a stainless braided kick down cable aswell.

With the kickdown disconnected and just the throttle cable and 2 return springs connected I have a nice feeling pedal. not to wishy washy but not firm either....feels great. But as soon as I hook the kick down cable to the car....its like pushing on a brick wall when I push the gas pedal ( it moves ...but somethings not right...it takes to much pressure to use the gas pedal with it hooked up).

My cables are all routed correctly as per lokar instructions (and it has the bracket mounted at the tailstock pulling the kickdown lever toward the rear of the car.....so its not an issue of being on backwards).

The cable is routed nicely with no sharp turns or kinks or bends and is away from exhaust also.

I can grab just the cable itself with my fingers and slide it in and out of the cable housing freely so its not binding in the housing.

I adjusted the kick down to lokars instrucktions ( held throttle wide open, then with pliers pulled the kick down cable all the way out as far as it would go and then locked the set screw in place.....basically full throttle is full kick down and closed throttle is no kick down).

I can get under the car and manually move the kick down lever It moves freely ...not rusted or stiff and it has some resistance to it...feels like its spring loaded.....but even what resistance I feel at the lever by hand doesnt seem like as much as the resistance I feel at the pedal that requires so much effort to push.

Anyone ran into this problem before?.....whats the fix? I have been racking my head all day trying different tweaks and I cant get a pedal feel that does not require the hulk to be my driver LOL.

Also another question. I have heard some guys say you cant run without the kickdown hooked up and some guys say you can run without it hooked up. I heard its an issue with line pressure....my question is.....does the issue only come into play when the vehicle is in "D" and the shifts are automatically controlled?....if so....can it be manually shifted 1-3 3-1 without the kickdown cable hooked up and without an issue.

why i ask is....my dad said when he was younger he had a duster and put headers on at which point he couldnt get the linkage to clear so he unhooked it and down shifted manually for kick down from then out and never had any issues with the trans acting up or burning up.

anyhow thanks in advance guys. Hopefully its a simple fix because this car keeps tossing curve balls at me the closer to the finish I get lol.

sorry for the long post, Thanks
 
And just to further clarify, my kick down is ran and adjusted just like it is instructed and show in the diagrams here [ame]http://www.lokar.com/downloads/pdf-instructions/chrysler-kickdown.pdf[/ame]
 
What brand carburetor are you using? Most brands require a Chrysler throttle pressure (kick down) cable adapter that corrects and synchronizes the two different lengths of cable travel between throttle, and kick-down.
An example of a Holley adapter bracket for Chrysler here:
http://www.holley.com/20-7.asp

Also another question. I have heard some guys say you cant run without the kickdown hooked up and some guys say you can run without it hooked up.
Click to expand...
When a Torqueflite is converted to full Reverse Manual shift valve body, the throttle pressure linkage or cable is to be detached. When running a stock stile automatic / manual shift valve body such as factory installed one must connect throttle pressure linkage or cable to carburetor or the front clutch pack will soon be burnt toast.
 
Thanks for the info.

I currently do not have the chrysler adapter ( I was under the impression it was only used when hooking a carburetor up to factor cable and bracket set ups.) and the lokar instructions for 904 show nothing about using the bracket and show it hooked up just as I have it hooked up. And I see COUNTLESS other people on this forum that have it hooked up exactly as I do.

I have had a holley carb on this car,multiple edelbrocks and currently a summit racing carb and they all made for a stiff pedal with the kick down connected.

Im not sure what the issue could be.
 
No thats all long gone, and I have to many clearance issues. it would be an even bigger headache lol. Id convert to manual valve body before going through all that.
 
Here is a picture of the current set up. ( dont mind the crud...havent got around to polishing and cleaning things up yet).

 
Also, for what it counts. I have tried installing 2 different sets of throttle cables now....aswell as 2 different sets of kick down cables.

same issue......so I dont believe its cable related.
 
i used a throttle cable like this and the inner tubing under the SS braid had kinked badly. Maybe check the sleeve for damage or hanging up somewhere.
 
No kinks . And like I said I've tried 2 different sets of cables and still same issue. And I can move the cable freely by hand.
 
Which is why i suggested install related! You say with out the kick down the throttle cable works good. Till you add in the kickdown. You got it looped around approaching the trans from the rear right?
 
To me the top cable looks like it needs to go up a hole....pulling it back where it is, there is no "swing/arch"???
 
Ok is the Kickdown an actual LOKAR brand or the off brand ones. I ask because with my throttle cable i noticed the cable was really flimsy. Hes got it in the right hole for the throttle. I have the knock off throttle cable and replaced the cable with a quality one from a Motorcycle throttle cable and was much better.
 
The TP valve is spring loaded, so what does it act like without those two springs you currently have on there?

I'm thinking this could be your cure.
 
Shouldnt have to do ankle exercises....it should simply just work right and I want to know why it does not.

Yes the cable is looped back and comfortably routed above the trans and up the rear of the block....no chance of a kink anywhere in the system.

I can unhook the kick down cable from the carburetor and push the gas pedal and it feels as it should. likewise I can from under the hood grab the inner cable and move it back and forth inside the housing without any binding at all. I can do the same by crawling under the car and moving the inner cable inside the housing from there aswell.

I can also from under the car with my hand manually move the kick down lever freely and it feels asthough it is spring loaded and has some tension on it (about the same kind of tension or maybe slightly more than the tension you would feel when manually moving your carburator linkage by hand). I am unsure if this is normal tension I am feeling or not.

All I know is that as soon as I hook the cable to the carb linkage and try to use the gas pedal.....its a joke. I have to push down hard enough that it almost lifts my *** out of the seat...nothing that ankle exercises will take care of lol.

As for brand .I have tried 2 different cables. one was high quality and the other was a knock off and they both felt the same.

as for the position of the carb linkage....it should be connected to the right spot. its where I have always hooked throttle cables and never had any issues. BUT I did for the heck of it try cobbing the throttle stud to the highest point of the linkage to see if that helped any....it did indeed take SOME of the effort out of the pedal....but was still ridiculously hard to push the pedal down.

And I do not want to try and bandaid fix something as critical and as dangerous as my throttle or my trans...so I am hoping to find the real reason as to what the heck is going on.

Seems like with as many people as have installed these cables and messed with similar setups that someone would have ran into something like this?.

I also thought about a bike cable or something but was not sure how I would go about adjustment ends and mounting etc...etc... Not to mention I am trying to figure out whats going on without throwing money at things until its fixed.
 
TrailBeast said:
The TP valve is spring loaded, so what does it act like without those two springs you currently have on there?

I'm thinking this could be your cure.
Click to expand...


Ive tried one spring aswell as no spring and its still stiff as crap to push the pedal.
 
4spdragtop said:
Show pics of the cable/bracket on the trans
Click to expand...



Im not currently near the car to take a picture of it. but it is routed EXACTLY like it is in the link above.

I have a ball stud on the kick down lever, from there the cable attaches and goes back to where the tail stock mounts to the trans where I have a cable bracket bolted that holds the adjuster/mounting nuts for the line. from there the cable gently loops along the top of the trans and up the back of the block where it then connects to the brackets on the carburetor with the adjusting/mounting hardware and then is attached to the carburetor linkage at the end of the cable.

nothing is kinked. nothing is collapsed,nothing is near exhaust, nothing is squished or pinched. its all free and clear. Ive been all over this thing.

to sit in the car and push the pedal you would think it had 20 return springs connected somewhere. it moves....but its just REALLY stiff.

I have even had my father look under the hood while I sat in the car and psuhed the pedal to see if there was something I was missing and all looked good. did the same thing with me under the car and him pushing the pedal. again all looked fine. I dont get it.
 
It looks to me like your kickdown has some slack. Notice your throttle cable is nice and staight and your kickdown is not! And your nearly out of adjustment on the carb side on your kickdown. Perhaps having someone under the car as well to make sure there isnt any slack underneath you cant see while under the hood.


Make final adjustments by holding throttle to wide
open and pulling the kickdown inner cable as tight
as possible. Slide cable stop up against Lokar Cable
Slide Fitting and tighten allen set screw. When the
kickdown is properly adjusted you should be able
to open the throttle to wide open position and there
should be no slack in the kickdown cable
 
My car acts just like yours does XMoparX. I didn't have a Lokar cable setup on it at first, just had the stock linkage and it did the same thing, I also always had the Trans-go kit in it. I believe part of the problem is the spring Trans-go sends in their kit that goes between the throttle pressure valve and governor valve is real stiff. Over twice as stiff as the stock spring. In addition Mopar used a few different length levers on the kickdown on the transmission and the shorter the lever is the least amount of leverage it has so the harder it pulls. Maybe yours is like mine and has a short lever. What I did to make it the best I could is only use one lower return spring, the smaller one (like Trailbeast said it's spring loaded so it doesn't need more than 1 return spring) and I moved the throttle cable position up one notch. It's still not as easy as not having the kickdown hooked up at all but it's drivable. The next step would be to locate a little longer kickdown lever. Not more than 1/2" longer or it'll throw the ratio off at the carb and make adjustments hard. One last thing, get some graphite cable lube and spray it down in the kickdown cable until it runs out the other end. I know it doesn't feel like there's any friction there when you pull it by hand but I guarantee there is and lube will help too. It'll also make the cable last longer.

Here's something to think of: when you pull the cable by hand your pulling it straight on aren't you? When the kickdown cable is hooked up to the carb it's pulling it at an angle. That makes it harder to pull. Try pulling it at an angle and you'll see what I'm saying.

Your dad got extremely lucky that running his car without a kickdown didn't toast the trans. The kickdown is really a throttle pressure linkage that varies the internal pressure to the clutch packs and front band in the trans. depending on how far the throttle is opened. If his car had a shift kit in it that may be why it lasted because shift kits generally raise the pressures in a trans.
 
If all the cable are free and move easily, and everything is fine without the TP connected then it HAS to be the TP lever or rod, or TP pressure valve spring, or a hung up TP valve.
In other words, it has to be in the valve body area.
You said you want to fix it right, so git er done and track it down.
Move the trans lever with the cable disconnected. (you did that)
Pull the pan and make sure the valve is moving in the valve body (I'd bet this is it, or the lever is not seated on the TP valve correctly)
Chk out the spring like Tracy suggests.
 
72ScampTramp said:
It looks to me like your kickdown has some slack. Notice your throttle cable is nice and staight and your kickdown is not! And your nearly out of adjustment on the carb side on your kickdown. Perhaps having someone under the car as well to make sure there isnt any slack underneath you cant see while under the hood.


Make final adjustments by holding throttle to wide
open and pulling the kickdown inner cable as tight
as possible. Slide cable stop up against Lokar Cable
Slide Fitting and tighten allen set screw. When the
kickdown is properly adjusted you should be able
to open the throttle to wide open position and there
should be no slack in the kickdown cable
Click to expand...


its because I took that picture after adding some slack to the adjustment trying to see if it made it easier to use the pedal.

And i followed those instructions aswell.

what I did was ...with my hand I floored the carburetor linkage all the way back and then zip tied it into place. Then with a set of pliers I grabbed onto the kick down cable and pulled it as far forward (front of car) as I could before it ran out of travel. While holding the cable out with pliers in one hand I ran the set screw that locks the cable forward to where the clip connects to the linkage and I locked down the set screw. so basically when the throttle is at wide open position....the kick down is fully engaged. and when the throttle is at 50% then the kickdown is 50% engages....so on and so on.
 
TrailBeast said:
If all the cable are free and move easily, and everything is fine without the TP connected then it HAS to be the TP lever or rod, or TP pressure valve spring, or a hung up TP valve.
In other words, it has to be in the valve body area.
You said you want to fix it right, so git er done and track it down.
Move the trans lever with the cable disconnected. (you did that)
Pull the pan and make sure the valve is moving in the valve body (I'd bet this is it, or the lever is not seated on the TP valve correctly)
Chk out the spring like Tracy suggests.
Click to expand...

I dont believe it to be an issue with the valve body as I just had it apart to install the tf-2 kit not long back and everything looked great and I was very precise with following the instructions to a T and everything went together as it should.

if anything I could believe what fishy68 mentioned with it being a stiffer spring rather than an actual issue or failure.

as I mentioned though, I can get under the car and manually move the kick down lever by hand...it has tension on it...spring loaded tension....doesnt bind or anything like that. it feels asthough it has about as much tension as you would feel on a carburators linkage when moving it by hand.

my issue is....I dont have another trans laying around to compare the tension to.....I dont know if the tension that I am feeling is "normal tension" or to stiff or?.

I appreciate the ideas though and I will keep them in mind...but before I go ripping the pan and valve body off I want to get some more ideas on things to check....if I still cant get it figured out then I will dig deeper into what the problem is.
 
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