Downshifting issues

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thrush544
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Downshifting issues

Post by thrush544 »

Hello,
I bought a 69 F-100 with a 302 from Florida, an original Georgia truck. The previous owner rebuilt the engine and did a very nice job. However I am having issues with her downshifting. The slightest incline induced petal push makes her downshift. Usually she'll jump from about 2700/2800 rpm clear to 3800.3900 rpm which is at the very limit of her torque curve and she is just sreaming and going nowhere fast. I cringe just waiting for a rod to go through the side of the block!!! :doh: The only adjustment I found on the kickdown rod would be to shorten it one hole. (I just looked at it qickly with my dad one dark evening.) Could it be the wrong rod, or would it kicking in sooner make it better if I shorten the rod. :hmm: Maybe he rebuilt the engine so it's out of poop by 3500 rpm. Whick would be puzzeling because it doesn'tseem to have an excessive lower end torque either. :zz:
I thank you all in advance for any help!
Take Care & God Bless,
Ed
"Courage is being scared to death, but saddling up anyway." - John Wayne

Proverbs 3: 5-6
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Re: Downshifting issues

Post by big block »

follow air vac line from carb or manifold to trans pull the hose off and there is sometimes an allen head adj inside the vac controll if it had been replaced good luck wes
69 bronco 4x4 - 70 bronco tube chassies 4x4 351-w c-6 - 65 f-100 w/69 429- c-6 - 03 ranger 4x4 - 99 f-350 4x4 diesel
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Re: Downshifting issues

Post by basketcase0302 »

I know that truck is no slouch! Seen it in action at a couple of our MNG's. There are several tranny adjustments you could try, (I would first start with the kickdown).
have an excessive lower end torque either. :zz:
Our "little 302's" as some folks on here call them...are not stump pulling low end torque monsters without putting some 4.56 gears into your 9". I'd bet that engine was not built for low end torque, but for mid range like most folks would use to tow with. :hmm:
Jeff
http://www.fordification.com/forum/view ... 22&t=46251
SOLD-71 F-350 dually flatbed, 302 / .030 over V-8 with a "baby"C-6, B & M truckshifter, Dana70/4.11 ratio, intermittent wipers, tilt steering, full LED lighting on the flat bed, and no stereo yet (this way I can hear the rattles to diagnose)! SOLD!
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Re: Downshifting issues

Post by fordman »

yes it could be a modulator adjustment. or it could be the kick down rod or linkage adjustment.
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thrush544
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Re: Downshifting issues

Post by thrush544 »

Thanks guys, Is there any bullitens, manuals or books where I can read up on this (of course when I read I :zz: )?
"Courage is being scared to death, but saddling up anyway." - John Wayne

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Re: Downshifting issues

Post by basketcase0302 »

Here's the only TSB that i could find that was even close to your downshifting issue:
http://www.fordification.com/tsb/viewto ... ?f=4&t=318

Maybe someone else with a little more experience with the kickdown rods will pipe in. :hmm:
Jeff
http://www.fordification.com/forum/view ... 22&t=46251
SOLD-71 F-350 dually flatbed, 302 / .030 over V-8 with a "baby"C-6, B & M truckshifter, Dana70/4.11 ratio, intermittent wipers, tilt steering, full LED lighting on the flat bed, and no stereo yet (this way I can hear the rattles to diagnose)! SOLD!
Many Ford bumps / one 76' EB / and several dents through the years.
A lot of "oddball" Ford parts collected from working on them for 34 years now!
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70_F100
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Re: Downshifting issues

Post by 70_F100 »

thrush544 wrote: The only adjustment I found on the kickdown rod would be to shorten it one hole.
If it's got more than one hole on either end, it's not stock.

The only kickdown adjustment from the factory was at the carburetor, where the linkage attached.
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Why is it that there's seldom time to fix it right the first time, but there's always time to fix it right the second time???

That's not an oil leak :nono: That's SWEAT from all that HORSEPOWER!! :thup:
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Re: Downshifting issues

Post by cdeal28078 »

I only have one factory 2v here in my shop to look at but I thought there was a screw or bolt at above the kickdown rod arm on the throttle to adjust the kick down? It has been a while since I have looked at one all hooked up though.
I also didn't think the Modulator valve would adjust the kick down RPM. I thought it works in conjunction with the governor to control the shifts of the transmission through one two and three. Probably wrong but at least if I am it might bring forth some conversation on the matter. lol
clint
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Re: Downshifting issues

Post by 70_F100 »

Clint, you're right about the adjustment. One screw on a small lever on the carb, assuming Motorcraft/Autolite 2100. :thup:

The modulator and governor also play a small part in the kickdown process. When I had the C6 in my truck, the kickdown linkage was never connected after I installed the 600 Holley. At certain speeds, kickdown would occur (mainly low speeds). By that same token, if I wanted to make SURE it dropped down a gear, I had to do it manually.

Of course, now that I have a T19, the kickdown rod is connected to my left foot and right hand... :doh: Much more positive now... :D
Wise men talk because they have something to say; fools talk because they have to say something.--Plato
Why is it that there's seldom time to fix it right the first time, but there's always time to fix it right the second time???

That's not an oil leak :nono: That's SWEAT from all that HORSEPOWER!! :thup:
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Re: Downshifting issues

Post by TX69F100 »

Without the kickdown linkage installed, the truck should never drop from 3rd to 2nd when you're on the throttle at cruising speeds. Kickdown linkage does not affect the 2/1. As was stated already, you should be able to tweak the amount of pedal required to achieve kickdown by an adjustment screw on the carb. Kickdown achieves the same result as pulling the shifter down into 2nd (it actually operates the same mechanism on the valve body). It will not allow the upshift until you back out of the throttle enough such that the lever is no longer depressed.
Brent

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