904 with Turbo Action shift kit, no 3rd

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73ScampSS

73ScampSS

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Hi everyone I am new to the forum here. I am having some issues with my transmission on a fresh rebuild.

It is a 1973 904, and I added a Turbo Action Cheetah Power shift kit, and it will not shift into 3rd gear.

I have had the rpms up to 5000 and speedo says 70 mph, which I know is not accurate since I added 3.55 gears. It goes into reverse, and shifts 1-2 solid and is great in 2nd, but will not hit 3rd.

I am wondering if this is a problem with the valve body since the internals seem to be working fine, or possible governor pressure problem.

Has anyone else had a problem like this? Thanks in advance for any help..
 
first thing is check your throttle pressure linkage..also called kick down linkage...if it not adjusted correctly it will not shift into 3rd...

simple test...remove the linkage at the carb..and drive the car around the block...the transmission should/will shift really quick from 1-2 and 2-3....if it shifts into 3rd the linkage is not adjust correctly...
 
Thanks for the reply.

Here is a pic of the kickdown cable I am using: http://ep.yimg.com/ca/I/chucker54_2198_28834775 and http://chucker54.stores.yahoo.net/accamobr.html

If it was not a rain storm outside right now I would go out and check it without the linkage hooked up.

A spring holds the lever full forward at the trans with throttle closed, and as throttle opens it pulls the lever back, is there some other adjustment needed from closed throttle other then having the full forward?

Thanks
 
I searched some past articles with "kickdown linkage"... it would appear I have it adjusted backwards... duh :banghead: ... i will have to try it out later when the weather dries up. thanks!
 
So.., I disconnected the kickdown cable and drove it around, it still shifts the exact same and doesn't ever hit third. I also adjusted the lever to be full back with WOT, and it shifts exactly the same. All the other gears are great, including reverse so I know all the clutches and bands are good.

I hate to pull the valve body off this thing for the 4th time.. its either going to get a $250 pro-stock valvebody with manual/auto capabilities, or I go the cheap route and un-engineer the shift kit out of it and figure out what went wrong.

Does anyone know if a problem in the throttle pressure adjustment would cause this? Any advice will help. Thanks..
 
I would pull the valvebody off and check the 2-3 shift valve.The 1-2 and 2-3 shift valve are next to each other in the valvebody.
Take an blow gun and put your thumb over long slot next to the steel plate farthest from the pressure regulator and with the blow gun shoot some air into the passage with your thumb blocking the rest of the port.
You should see both valves move back and fourth with the air pressure.
When you have taken the v.b off,did you take it apart?putting a valve in backwards or leaving screws loose or over tighting screws will also cause problems.
If this was a working unit before your rebuild,you should be able to find the problem.Shift kits just add to the fun.
Also air check your your clutch drums through the case in the front,if you have a cut seal it may be possible have reverse because of a higher working line pressure in reverse.
When you reassemble the t.v lever make sure your e clip is on the shaft.I have seen people ram the lever on and the lever inside will get jammed in between the pressure adjustment and the bracket causing no rise in line pressure.
If it is all to still in the car do a line pressure test to check your pump pressure.
Good luck keep at it you will find your problem:D
 
hey, if the above advise dosent help and you have the valve body off again, spilt it and check the large checkball by the pressure regulater valve. it sits in a slot we call a bathtub. make sure the ball size is 11/32 and not 3/8. the larger ball binds against the seperator plate and cant move.
 
zijmer said:
hey, if the above advise dosent help and you have the valve body off again, spilt it and check the large checkball by the pressure regulater valve. it sits in a slot we call a bathtub. make sure the ball size is 11/32 and not 3/8. the larger ball binds against the seperator plate and cant move.
Click to expand...

Yes, you want to have your balls in the right spot.
 
finally got a PSI gauge on my 904, in "D" and 1st gear, with all the wheels off the ground, line pressure was 0-zero. ...??... yes zero. :wack: when it hit second gear line psi jumped to 8 psi. it never hits 3rd, so... .. I pulled the throttle lever all the way open while revved up in second gear and line pressure slowly rose to 90 psi, which is what should happen. :hello1: When I let go of the throttle lever then Line psi goes back to zero. In reverse there is also -zero- line pressure and the spec says 230-260 psi.

The service manual says incorrect Throttle Pressure adjustment will give bad readings out of the Line Pressure Port even when Line Pressure is set correctly. Since the other gears work fine, I am thinking this may be the case???? I have not yet checked GOV pressure. I know the Line Pressure screw should be 1,5/16" from the valve body, but Throttle Pressure requires a special spacer tool.. does anyone know where to find this tool or the length of it, or another way to set the throttle psi, and does this sound like I am on the right track???
 
Im plugged in on the passenger side of trans, second port back, on the accumulator.

I'm thinking I could run it again, and pull the lever until PSI is at spec, then lock the lever down, pull the pan and adjust the Throttle PSI stopper screw until it just touches the throttle valve??

With the pan off and kickdown lever all the way forward, the throttle pressure adjustment screw does not touch the throttle valve, so I am thinking it must not be adjusted correctly??
 
With the TV valve at rest on the valve body, there should be an 1/8 inch gap between the cam and the tip of the TV. Set your stop there.
The throttle linkage should be set so the trans pressure just starts to increase when the throttle is moved off idle. And the throttle linkage should be all the way back at full throttle. Leave a little play in the throttle linkage at full throttle so it doesn't bind.
When you drive it you'll have to adjust your shift points.
 
This has been a long time coming, but after many other projects come and gone, I decided I better pull the Scamp back out and fix this old transmission problem. I think I finally found the problem, but I wanted to go over it with people who have much more experience (you guys). So,

After adjusting the throttle pressure on the valve body with a custom tool, I hooked the pressure gauge onto the line pressure port on the 904. In "D," wheels off the ground, PSI begins to show at about 30mph --> It jumps to about 50psi/30mph/1000rpm. With throttle lever pulled all the way, it increases to 86psi. Here are some other readings I got: 72psi/37mph/92psi(w throttle pulled), 64psi/40mph/90psi(w throttle pulled), 70psi/50mph/94psi(w throttle pulled), then it went back to 40psi/33mph at idle-900rpm and 86psi with throttle pulled back.

My FSM says kickdown release pressures should match the Line pressure readings. I plugged into the kickdown servo release port (front port on the passenger side). I got zero psi, no matter what RPM/MPH I was at. I raised it to 5000rpm and had zero psi on the gauge. FSM says this could be caused by front servo leakage, or front clutch leakage. My problem is "no 3rd gear." This was a brand new rebuild (years ago) and I swear I already pulled it back out a 2nd time to fix this problem. I am wondering if you guys can throw me some insight, if there is no other possibility but excess front clutch leakage. I swear I did a air test before installing it last time. This sucks, but I need to get this car back on the road.

My GOV pressures: 30mph-4psi, 40mph-20psi, 45mph-35psi, 50mph-48psi, 60mph-55psi. They seem to be in spec, though I doubt my speedo is accurate seeing that it sticks at 25mph.

Do you guys also think this points to front clutch leakage? I have found excess clutch mud in the pan on several occasions. Reverse is fine as always. Please let me know what u think.
 
The front clutch is also active in reverse. If it were leaking you either wouldn't have reverse or it'd slip bad in reverse. If the front servo was leaking you probably wouldn't have 2nd gear because the front servo applies the front band which gives you second gear. I realize dropping the VB is a hassle but you really should verify the large check ball in the valve body channel is 11/32" as recommended by several guys already. If you mixed up the 3/8" line pressure ball with it things will go together but you won't have high gear. The other recommendation to check the 2-3 shift valve by Bronzebee is valid also. Either of those would most likely be the reason your not seeing any pressure at the kickdown release port because the only time you'll see pressure at the release port is when it releases, in other words when it shifts into 3rd gear. If it's staying in 2nd gear it's not releasing.
 
Thanks for the advice, I was going to pull the valvebody anyway to do another air test before I pulled the engine for an in-car trans teardown.

Everything on this car is a real pain because its a Slant with headers and they run so close to the trans that the pan is hard to get off and any messing with the linkage is tough.

I will go back through the valvebody and make sure all the checkballs are in the right spots before going any further. Thanks
 
Sorry its been so long, but I finally have an update on the 904 situation. I have the valvebody out on my bench, and I had previously installed a MP shift improver and a Turbo Action Cheetah shift kit #17810.

The MP kit says remove the accumulator spring and put a blocker rod in to hold it down, and turn up the line pressure to max. **I did not increase the line pressure after installing the kit the first time.

The Turbo Action kit adds some plugs and a separator plate. I checked the 2-3 shift valve as BRONZEBEE mentioned and it was perfect. All the balls were also in the right places. The directions for the TA kit are hand drawn and terrible, and I cannot figure out if I installed everything right the first time: The kit shows to remove a spring and put a plug in its place for the 2-3 or 1-2 shift valve, and I cannot figure out which one. The plug only fits in the 2-3 hole and its loose, but the drawing shows it going in the 1-2 hole. ***I also left the spring in the first time.

I am not sure if these two issues could be causing my No-3rd issue, or if the kits are somehow conflicting. I want to get this figured out before I put the valvebody back in again. Thanks all.
 
EUREKA I'VE GOT IT!
I decided to pull the governor plug off the end of the 2-3 shift valve, and I found the valve was not moving at all. How can it 2-3 shift without the valve moving!?!?!

I was wrong all along~ I thought the plug provided with the shift kit was an extension of the throttle plug and only limiting the 2-3 shift valve travel, but it was stopping it from moving all together. I opened the governor side of the 2-3 shift valve, and realized the valve had no room to move. bingo

Here is the crude drawing in the shift kit:
http://s766.photobucket.com/user/goodbyehorse/media/IMG_1708b_zps3b6dae4b.jpg.html
You can see how a noob fresh out of auto school could make this mistake.. I put the plug in the only hole where it fit; with the 2-3 shift valve. The drawing shows three valves on the body, but my 904 only has two (the 1-2 and 2-3). This shifting problem has kept my poor Scamp off the road for 8 years!!

Look out Norcal, there is a new Scamp out on the streets... with fresh break-in oil and a fresh engine. Finally this day has come. After 8 years, and three times pulling the engine and trans, I see I DO know how to rebuild Torqueflites after all... And I'm NOT going crazy. Time to polish the Torq-Thrusts, reinstall the subwoofers, replace the new suspension boots which have all since cracked(dang it!), tune the Holley 390, and finish this long term project.
 
73ScampSS said:
This has been a long time coming, but after many other projects come and gone, I decided I better pull the Scamp back out and fix this old transmission problem. I think I finally found the problem, but I wanted to go over it with people who have much more experience (you guys). So,

After adjusting the throttle pressure on the valve body with a custom tool, I hooked the pressure gauge onto the line pressure port on the 904. In "D," wheels off the ground, PSI begins to show at about 30mph --> It jumps to about 50psi/30mph/1000rpm. With throttle lever pulled all the way, it increases to 86psi. Here are some other readings I got: 72psi/37mph/92psi(w throttle pulled), 64psi/40mph/90psi(w throttle pulled), 70psi/50mph/94psi(w throttle pulled), then it went back to 40psi/33mph at idle-900rpm and 86psi with throttle pulled back.

My FSM says kickdown release pressures should match the Line pressure readings. I plugged into the kickdown servo release port (front port on the passenger side). I got zero psi, no matter what RPM/MPH I was at. I raised it to 5000rpm and had zero psi on the gauge. FSM says this could be caused by front servo leakage, or front clutch leakage. My problem is "no 3rd gear." This was a brand new rebuild (years ago) and I swear I already pulled it back out a 2nd time to fix this problem. I am wondering if you guys can throw me some insight, if there is no other possibility but excess front clutch leakage. I swear I did a air test before installing it last time. This sucks, but I need to get this car back on the road.

My GOV pressures: 30mph-4psi, 40mph-20psi, 45mph-35psi, 50mph-48psi, 60mph-55psi. They seem to be in spec, though I doubt my speedo is accurate seeing that it sticks at 25mph.

Do you guys also think this points to front clutch leakage? I have found excess clutch mud in the pan on several occasions. Reverse is fine as always. Please let me know what u think.
Click to expand...

This statement freaks me out a bit. "several occasions" ?
 
Definitely not the best drawing but it looks to me like the blocker rod is meant for the shuttle valve. Someone correct me if I'm wrong but I'm pretty sure all had a shuttle valve. Not all have the shift control valve which is the 3rd valve on the left in the drawing. The shuttle valve is the valve on the top of the valve body.
 
fishy68 said:
Definitely not the best drawing but it looks to me like the blocker rod is meant for the shuttle valve. Someone correct me if I'm wrong but I'm pretty sure all had a shuttle valve. Not all have the shift control valve which is the 3rd valve on the left in the drawing. The shuttle valve is the valve on the top of the valve body.
Click to expand...
you are correct. they all have a shuttle valve, but not all have the 1-2 control valve.
 
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