driving my 904 with no kickdown lever attached

Posted By: bigdaddywiz

driving my 904 with no kickdown lever attached - 07/31/11 07:37 PM

after getting my car back together and running, i have everything but the lokar cable needed for my setup (4bbl/340 intake on my 318) for kickdown on the 904. now, i know this can cause damage if not driven lightly, but i decided to take the car out a few times around the area to make sure everything is good, which it is.

i've read that the kickdown linkage governs the amount of fluid pressure in the trans. a thing i noticed on my linkage when it was stock was that the kickdown linkage did not even move until the throttle was at or near WOT...so with that in mind i took it out a few times with NO linkage hooked up to my new setup...

i am NOT taking it on the highway.

i am NOT make WOT runs.

i am gently easing into the throttle, maybe only getting to half throttle and the car shifts normally as it always has.

i never get myself into a situation where i would make the car lug in a higher gear and not allowing it to downshift.

so in short, i've been taking it easy. i have a lokar cable on the way. am i doing damage?

thanks

Posted By: 1_WILD_RT

Re: driving my 904 with no kickdown lever attached - 07/31/11 07:43 PM

If you must drive it find a way to hold the lever on the trans half way back, bailing wire, zip tie... Whatever..

Posted By: Kern Dog

Re: driving my 904 with no kickdown lever attached - 07/31/11 07:46 PM

I'd say that you are doing "some" damage, but maybe in the way of accelerated wear but not exactly outright abuse.
The "throttle pressure linkage" as the factory called it, should be connected at all times. Heck, I've done what you are doing, and suffered no ill effects. Its probably more risky with a worn out trans.
The lever on the carburetor stud should start to move once the throttle moves, and the carb should reach WOT as the trans lever bottoms out. Thats in a perfect world anyway....

Posted By: MoparforLife

Re: driving my 904 with no kickdown lever attached - 07/31/11 08:39 PM

There should be a small spring pulling the linkage forward to have contact with the throttle pin throughout the travel of the throttle. (number 13) This allows the transmission to vary the throttle pressure to control the shifting and shift points in the transmission. With out this hooked up it can/will lead to excessive slippage from lack of pressure.

Posted By: 70Cuda383

Re: driving my 904 with no kickdown lever attached - 07/31/11 09:58 PM

I don't know why it worked....but it did. I drove my car for 10,000 miles without any problems, without that hooked up. never got it to work right, always shifted way too early no matter how I hooked it up. I ultimatly just drove it like a manual valve body and would control the shifts by manually shifting from 1, 2, D, while driving.

maybe forcing the shifts with the manually shifting saved the trans, I don't know.

all I know is that the transmission never fried itself, and the fluid was always nice and red, never slipped etc.

worked great till my brake booster developed a vacuum leak, caused half the motor to go lean, and I burnt 3 exhaust valves. that's when I pulled it all apart to start the restoration

Posted By: John_Kunkel

Re: driving my 904 with no kickdown lever attached - 07/31/11 10:20 PM

Quote:

I don't know why it worked....but it did. I drove my car for 10,000 miles without any problems, without that hooked up. never got it to work right, always shifted way too early no matter how I hooked it up. I ultimatly just drove it like a manual valve body and would control the shifts by manually shifting from 1, 2, D, while driving.

Another classic example of the difference between doing it wrong and getting away with it and doing it right. Some people are just luckier than others.

Posted By: MoparforLife

Re: driving my 904 with no kickdown lever attached - 07/31/11 10:51 PM

Quote:

Quote:

I don't know why it worked....but it did. I drove my car for 10,000 miles without any problems, without that hooked up. never got it to work right, always shifted way too early no matter how I hooked it up. I ultimatly just drove it like a manual valve body and would control the shifts by manually shifting from 1, 2, D, while driving.

Another classic example of the difference between doing it wrong and getting away with it and doing it right. Some people are just luckier than others.

Posted By: SLOW67

Re: driving my 904 with no kickdown lever attached - 08/01/11 02:09 AM

Quote:

Quote:

I don't know why it worked....but it did. I drove my car for 10,000 miles without any problems, without that hooked up. never got it to work right, always shifted way too early no matter how I hooked it up. I ultimatly just drove it like a manual valve body and would control the shifts by manually shifting from 1, 2, D, while driving.

Another classic example of the difference between doing it wrong and getting away with it and doing it right. Some people are just luckier than others.

When I first got into mopars.....at 16 I didn't know any better and burned up two 904s by not having the kickdown on. Even wired half way open and shifting it manually my little 273 ate 2nd gear after about 200 miles in my Valiant. I guess some people get lucky but I'm not trying it again

Posted By: RapidRobert

Re: driving my 904 with no kickdown lever attached - 08/01/11 03:54 AM

What RT said, halfway back & only minimum throttle shifts & try & stay away from driving (it) as much as you can till the parts come in

Posted By: MarkZ

Re: driving my 904 with no kickdown lever attached - 08/01/11 06:40 AM

Quote:

When I first got into mopars.....at 16 I didn't know any better and burned up two 904s by not having the kickdown on. Even wired half way open and shifting it manually my little 273 ate 2nd gear after about 200 miles in my Valiant. I guess some people get lucky but I'm not trying it again

I did the same thing at that age and killed a 904 in about 40 miles. Wound up losing second gear.

Really, you shouldn't be driving it at all without that linkage installed and properly adjusted. You're just inviting trouble.

Posted By: scratchnfotraction

Re: driving my 904 with no kickdown lever attached - 08/01/11 01:23 PM

thats how i learned about throttle pressure linkage

lose 2nd..tighten band...lose 2nd...tighten band...lose 2nd tighten band... eat the drum up and fill with metal shavings...change trans..

took a couple to learn though..i is slow in the brain

now I got a manual VB put in and it locks up going into 2nd and 3rd,and here I thought i could just bolt in a manual VB and have no linkage...

I be R&R it and going back stock with a throttle pressure linkage set up

so see...it is best to have it from the get go and leave it alone after its adjusted and set correctly.

good luck trans hunting in the JY

Posted By: dOc !

Re: driving my 904 with no kickdown lever attached - 08/01/11 01:35 PM

Quote:

so in short, i've been taking it easy. i have a lokar cable on the way. am i doing damage?

thanks

I say .... Absolutely NOT. But I would say a max of 1/4 throttle would be the only safe-zone. And taking it on the highway - 60 mph - even less of a prob.

Posted By: bigdaddywiz

Re: driving my 904 with no kickdown lever attached - 08/01/11 08:26 PM

thank everyone...i've had it out for way more than 40 miles! you must have been hammering on it for it to fail with just that many miles!

no signs of failure, no slipping, shifts fine...with that said though, i aint driving it till i get the lokar cable installed

some of your posts scared me!!

i still dont understand how if the arm never moved until at full throttle originally, how would i be doing damage now if i stayed below half throttle?

Posted By: dOc !

Re: driving my 904 with no kickdown lever attached - 08/01/11 08:49 PM

Quote:

i still dont understand how if the arm never moved until at full throttle originally, how would i be doing damage now if i stayed below half throttle?

The arm moves ALL THE TIME .. not just WOT. IF you have a 100 psi gauge ...hook-it-up to the middle port on the pass side .. just above the pan rail. What kind of psi do you have ?

Posted By: scratchnfotraction

Re: driving my 904 with no kickdown lever attached - 08/01/11 08:49 PM

it moves as the throttle lever moves and at the same time/rate/distance

it will raise the pressure as the rpm goes up to hold the clutches from slipping.

when the carb hits WOT so should the tranz lever,it should be most of the way back to all the way back,dont let it go back so far it wont let the carb get WOT...thats too much!

I think?

Posted By: Anonymous

Re: driving my 904 with no kickdown lever attached - 08/01/11 08:51 PM

Quote:

thank everyone...i've had it out for way more than 40 miles! you must have been hammering on it for it to fail with just that many miles!

no signs of failure, no slipping, shifts fine...with that said though, i aint driving it till i get the lokar cable installed

some of your posts scared me!!

i still dont understand how if the arm never moved until at full throttle originally, how would i be doing damage now if i stayed below half throttle?

The "kickdown" linkage moves the instant the throttle is applied if adjusted correctly and increases pressure to ensure the clutches don't slip. Even a little pressure increase helps.

It may not be slipping now, but it's real easy to damage the clutch packs when driving without a "kickdown"

Posted By: AARCONV

Re: driving my 904 with no kickdown lever attached - 08/02/11 11:37 PM

the damage is already done, you just won't know to what extent if any, till time......

Posted By: bboogieart

Re: driving my 904 with no kickdown lever attached - 08/02/11 11:47 PM

Yep has to be on and has to be adjusted right. Guess how I know. I did what you are doing. A year later I was putting another trans in.

I know same old song. But Tis True Tis true!!!

Posted By: BDW

Re: driving my 904 with no kickdown lever attached - 08/03/11 01:05 AM

If you have a fully manual valve body, the kickdown linkage is not needed?

Posted By: scratchnfotraction

Re: driving my 904 with no kickdown lever attached - 08/03/11 01:13 AM

correct,full manual VB does not use the TPV linkage

I have the CRT manual VB to drop the linkage on my truck

Posted By: buildanother

Re: driving my 904 with no kickdown lever attached - 08/03/11 01:13 AM

Correct.

Posted By: dOc !

Re: driving my 904 with no kickdown lever attached - 08/03/11 01:18 AM

Naughty boyz ... you are uNcorrect ....

While MOST manual VB's do not use the TP linkage ..some do.

JUST so ....you know ...

Posted By: scratchnfotraction

Re: driving my 904 with no kickdown lever attached - 08/03/11 01:20 AM

I use the one with no stud sticking up for a lever to fit on

it has broken the trans already too

Posted By: buildanother

Re: driving my 904 with no kickdown lever attached - 08/03/11 01:24 AM

Mine surely uses no throttle pressure linkage, keeps engine bay cleaned up.

Posted By: joedust451

Re: driving my 904 with no kickdown lever attached - 08/03/11 03:29 AM

Quote:

Quote:

Quote:

I don't know why it worked....but it did. I drove my car for 10,000 miles without any problems, without that hooked up. never got it to work right, always shifted way too early no matter how I hooked it up. I ultimatly just drove it like a manual valve body and would control the shifts by manually shifting from 1, 2, D, while driving.

Another classic example of the difference between doing it wrong and getting away with it and doing it right. Some people are just luckier than others.

When I first got into mopars.....at 16 I didn't know any better and burned up two 904s by not having the kickdown on. Even wired half way open and shifting it manually my little 273 ate 2nd gear after about 200 miles in my Valiant. I guess some people get lucky but I'm not trying it again

The exact same thing happened 2 me back in the 80s when i got into Mopars, burned 2nd. gear in a 904, then burned 2nd. gear in a 727, I learned my lesson, still raced it alot on the streets, went from 1st. too 3rd & still won alot, Top end on that 340 was great, at one time i push it to about 130

then backed out.

Posted By: BDW

Re: driving my 904 with no kickdown lever attached - 08/04/11 01:42 AM

Thx for the reply, I guess my MVB doesn't need the linkage, been driving it without for 10yrs. Hope I'm not just 1 of the lucky ones.

Posted By: joedust451

Re: driving my 904 with no kickdown lever attached - 08/04/11 03:33 AM

Quote:

Thx for the reply, I guess my MVB doesn't need the linkage, been driving it without for 10yrs. Hope I'm not just 1 of the lucky ones.

Your not, You no longer need the KD with a MVB, the line pressure stay around 200 at all time, so don't sweat it, your good.