Fresh 904 No Shift

[JimKueneman]

Took my Coronet for its maiden voyage to the corner store for gas and the newly rebuild transmission won't shift out of LO. I checked the fluid and it was a pint low so I topped it off but I am sure that is not it. Also the bell housing had a drip of fluid already, lastly the speedo does not work. I verified it is plugged into the speedo housing fully (when the dash was out if spun the cable in the housing to make sure the needle work and it did). I also cleaned and lubed the cable so I am sure it is fully seated on both ends. Is that at clue?

Could I be doing something wrong?

Jim

 

[moparcrazy]

how about the kick down linkage, is adjusted properly, if its not it wont shift

 

[JimKueneman]

how about the kick down linkage, is adjusted properly, if its not it wont shift

Well I made a custom kick down to work with the FiTech on a 318. I thought I got it correct....

 

[JimKueneman]

Does the above look correct?

 

[JimKueneman]

So if I shorten the rod so it does not push on the kick down rod so early will that force earlier shifting (to see if I can get it to shift)?

 

[moparcrazy]

Looks Good to me, but whats it doing down below, and like you said maybe its to long and staying in the kick down Mode not letting it up shift, try disconnecting the kick down to see if it shifts,
but don't drive it like for a long time.

 

[JimKueneman]

Looks Good to me, but whats it doing down below, and like you said maybe its to long and staying in the kick down Mode not letting it up shift, try disconnecting the kick down to see if it shifts,
but don't drive it like for a long time.

If I do that I need to keep it pulled forward though correct.

 

[miller]

So if I shorten the rod so it does not push on the kick down rod so early will that force earlier shifting (to see if I can get it to shift)?

Doesn't matter, but video won't work on mine. First, do you have a service manual? It would help to be able to look this stuff up, to understand things. Second...do you know if the bands are adjusted right, besides the other stuff on the shift body.

The kickdown/throttle pressure...especially if the linkage is 'homemade'. Understand there are different length levers for that, the one on the trans itself. The 'swing', or total movement of the lever needs to match, with the swing at the throttle arm of the carb. Needs to be like that, so when the kickdown linkage moves, it has full travel.
Unhook the kickdown linkage at the carb. Then, push the linkage back, to see if it works freely, and springs back, since it's spring loaded. Also compare the 'swing', or travel, of both the kickdown linkage, and the arm that linkage mounts to, on the carb throttle arm. Needs to be about the same...or the linkage pin is located wrong. Simple adjustment...carb at WOT, kickdown linkage pushed fully back, the slot should fit onto the throttle arm pin, with the pin just off the rear of the slot.

Speedo stuff...where the cable hooks into the trans. Need to know how many teeth on the plastic gear. With that number, where the cable mounts, is a rotator, that is turned to a certain mark, to engage the speedo gears.

 

[AR67GTX]

Hard to tell from the video - but is the linkage clearing the firewall at full throttle?

Even if not completely adjusted correctly, it looks good enough that it should be shifting at part throttle.

If you disconnect it, leave it forward to keep pressure low to allow the governor to initiate a shift. Just go for a very short distance to try it. But, I suspect something else is not right.

 

[JimKueneman]

Doesn't matter, but video won't work on mine. First, do you have a service manual? It would help to be able to look this stuff up, to understand things. Second...do you know if the bands are adjusted right, besides the other stuff on the shift body.

The kickdown/throttle pressure...especially if the linkage is 'homemade'. Understand there are different length levers for that, the one on the trans itself. The 'swing', or total movement of the lever needs to match, with the swing at the throttle arm of the carb. Needs to be like that, so when the kickdown linkage moves, it has full travel.
Unhook the kickdown linkage at the carb. Then, push the linkage back, to see if it works freely, and springs back, since it's spring loaded. Also compare the 'swing', or travel, of both the kickdown linkage, and the arm that linkage mounts to, on the carb throttle arm. Needs to be about the same...or the linkage pin is located wrong. Simple adjustment...carb at WOT, kickdown linkage pushed fully back, the slot should fit onto the throttle arm pin, with the pin just off the rear of the slot.

Speedo stuff...where the cable hooks into the trans. Need to know how many teeth on the plastic gear. With that number, where the cable mounts, is a rotator, that is turned to a certain mark, to engage the speedo gears.

• Yes I have the manual, I had a local transmission shop rebuild it. The guy is a Mopar owner so it should be built right.
• Yes the kick down goes from stop to stop with the full swing of the throttle. I was very careful in understanding and duplicating the geometry when I made the linkage
• One think I did not notice is the first 1/2 travel of the kick down has almost no resistance to it then at about 1/2 way I can feel it hitting a spring and it had push back after that. I think this is correct based on the old Chrysler kick down adjustment training video on youtube.
• I am pulling the cable off the transmission this morning, will look at that.

 

[miller]

One think I did not notice is the first 1/2 travel of the kick down has almost no resistance to it then at about 1/2 way I can feel it hitting a spring and it had push back after that.

Yeah, that sounds right. In the trans, when the throttle pressure lever is adjusted right, there's free play before the lever makes contact with the valve. Just want the kickdown right, or you'll burn up the trans.
Book will show you the right setting, for each speedo gear, on the rotator.

 

[JimKueneman]

The shop put it on the wrong notch for the speedo. It has granny gears (2.94) so it was wrong. Works now. Also shortened the rod and it will shift if I gun it on a down hill then let off the throttle it will shift up. Just shorted the vertical rod so now I have a good 1/2" of nothing before it engages the rod. Going for another test drive after breakfast.

 

[dvw]

Disconnect the kick down. Does it shift now?. Still no upshift? Governor may be stuck or valve body issue.
Doug

 

[JimKueneman]

Ok I have NO idea what happened. I added about a half a quart of tranny fluid last night and threaded back the kick down so it had 1/2" of freeplay before the throttle moved it. It shifted going to the store so I took it out on the open road and by the time I got done I had the kick down exactly where it was adjusted yesterday where I started.....

 

[RJRENTON]

Jim,
Beside A/C i know a little about how the 904 (and the A727A or A727B) is supposed to operate.
With regard to what the "kick down" rod is or does, i ask you whether your car's system has a 2 piece rod with a bellcrank or a one piece rod? What the system does is: determines or modifies the line pressure (which affects shift quality and speed) AND when the shift occurs, based or drive shaft RPM. It does this by increasing the line pressure as the speed increases by increasing governor pressure so the shift point is firmer to reduce clutch slippage under increasing torque generation. Remember a Mopar trans shifts by the timing of a band release and a clutch application until direct, when there are only clutches engaged (and no bands).
The kick down rod adjustment begins at the carb, where the long slotted adjustable end is in constant contact with the throttle shaft stud. Unscrew it until it is in contact. Refer to the Mopar shop manual, NOT MOTORS OR CHILTONS, AND IGNORE anyone that equates the operation to a GM THM 350 or THM 4OO transmission. The adjustment method is simple.....the bell crank is pinned to the pivot bracket with a twist drill to set the initial position and Length of the first rod.
Rather than getting into a Pi**ing contest with others, PM me and I'll walk you through the process....it's very simple and easy....I've done it many times b4.
Cheers,
Bob Renton

 

[JimKueneman]

Thanks Bob, I think I have it. It is a 2 piece so it is a bit of a balancing act to get the full travel at the transmission. Converting the 318 to a 4 barrel EFI required some fabrication. Now that it is actually working I just need to get things dialed in.

 

[dvw]

The distance between the throttle shaft and throttle linkage attachment point on the 4 barrel is different than a 2 barrel. This requires a corsponding change in length of the throttle pressure arm at the trans to maintain proper travel. There are at least 2 different length factory throttle pressure arms.
Doug

 

[JimKueneman]

The distance between the throttle shaft and throttle linkage attachment point on the 4 barrel is different than a 2 barrel. This requires a corsponding change in length of the throttle pressure arm at the trans to maintain proper travel. There are at least 2 different length factory throttle pressure arms.
Doug

Correct. This is a FiTech TBI with the Holley carb adapter. I carefully measured the throw from shaft center to connection point and I modified the Holley carb adapter to fit the FiTech with the exact same throw. From the transmissions point of view it should not see anything different that it did with the 2 barrel I think.