Need help with 4 spd transmission wont shift while on the bench. (1 Viewer)

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78fj40mg

TLCA #23510
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This morning I was getting ready to install my 4spd transmission so I was checking to see that everything is working OK prior to installing the tranny and realized that it does not shift between gears at all. So I removed the shifting cover off to see if it was hanging up and all looked OK the shifting forks are aligned perfectly so is the reverse fork. Then I can turned the input shaft clock wise and the output shaft turns counter clock wise, is it stuck in reverse?
I cannot find neutral, is there a method of finding neutral and installing the cover correctly?

I've tried searching here but cannot find any reference to this problem, I appreciate your help in advance. Thank you.

I can't tell which gear it's in
IMG_20140927_162808.jpg


Shifting forks in neutral
IMG_20140927_162932.jpg


IMG_20140927_162902.jpg


IMG_20140927_162853.jpg


IMG_20140927_162655.jpg
 
Last edited:
Guessing your transmission is in reverse and your putting the shifter into another position. The shifter is down and to the left when in reverse. If you look in the opening you should be able to where the groove right shift plate is higher then the center and left plate. With a large screwdriver move the groove down to match grooves in the other two plate. Then install the shifter in the neutral position.
 
Guessing your transmission is in reverse and your putting the shifter into another position. The shifter is down and to the left when in reverse. If you look in the opening you should be able to where the groove right shift plate is higher then the center and left plate. With a large screwdriver move the groove down to match grooves in the other two plate. Then install the shifter in the neutral position.

The shifter plates do not move enough to change gear, the large shifter plate only moves a 1/4 inch towards the back, the small one doesn't move at all. The output shaft turns counter clock wise which leads me to believe it's in reverse.
 
OK I was able to move the large shift plate but it didn't make a difference, still cannot shift into gears.
 
You have to line everything back up so the shifter goes back in in neuteral. Take your time when doing this and remember that the bottom of the shifter moves in the opposite direction as the top. Dont lose the springs under the shift plate dealie like I did. Once you have it in n youll be able to insert the shifter and row the gears. Do this before clipping the shifter retainer dealie back in just in case you have to mess around more.

D
 
You have to line everything back up so the shifter goes back in in neuteral. Take your time when doing this and remember that the bottom of the shifter moves in the opposite direction as the top. Dont lose the springs under the shift plate dealie like I did. Once you have it in n youll be able to insert the shifter and row the gears. Do this before clipping the shifter retainer dealie back in just in case you have to mess around more.

D

Darwin thanks for the response! I'm not very familiar with the internal gears of the four speed tranny, can you walk me through to line up the gears back to neutral?
How do you know when they are all in neutral? And how do I move the gears?
Thanks
 
If the transmission was working before being removed and you didn't do anymore then pull the shifter then aligning the three plates should fix your problem. If the input and output shaft were able to move by hand and were going in opposite direction the transmission is in reverse. Only the right plate is out of neutral. If any of the other plate were any place but neutral you would not be able to move the shafts by hand. Using a large screwdriver or other type of pry bar move if from the upper position to the center. You might need to use a hammer on the screwdriver handle to get the plate to snap into neutral. Once in neutral you should be able to hold one shaft and move the other one. Your pictures didn't show up but it you still need help I can snap pictures tomorrow from a H42. Have few of them around here.
 
If the transmission was working before being removed and you didn't do anymore then pull the shifter then aligning the three plates should fix your problem. If the input and output shaft were able to move by hand and were going in opposite direction the transmission is in reverse. Only the right plate is out of neutral. If any of the other plate were any place but neutral you would not be able to move the shafts by hand. Using a large screwdriver or other type of pry bar move if from the upper position to the center. You might need to use a hammer on the screwdriver handle to get the plate to snap into neutral. Once in neutral you should be able to hold one shaft and move the other one. Your pictures didn't show up but it you still need help I can snap pictures tomorrow from a H42. Have few of them around here.

I gave up for today after working on this tranny for over four hours and still can't get it into neutral, I'd appreciate several pictures showing where the plates need to be for the neutral location.

This is where I left it tonight, do I move the red or black?
IMG_20140927_162808copy_zpsc6a2f1e1.jpg
 
The main shaft gears are in N, but the reverse gear is engaged. You can see the fork that moves it to the left of the red arrow. There is no detent to hold it in position, so it tends to slide around. Put a dab of wheel bearing grease on the reverse gear shaft to stick it in N position. You can tell if it is in N when you can turn the output shaft and the input shaft/counter shaft does not rotate.

Alternatively, you could put the top cover in R and then isntall it.
 
I think Pin_Head has you covered. Having removed the top cover that changed everything. If you look at the top cover it have two large forks that fit the two collars on the main shaft with all the showing gears. Then there a arm with a small fork at the end. The fork has to go over the pin on the reverse gear lever. Since you have the transmission out you can elevate one end which will help keep the reverse lever in the neutral position.
 
I think Pin_Head has you covered. Having removed the top cover that changed everything. If you look at the top cover it have two large forks that fit the two collars on the main shaft with all the showing gears. Then there a arm with a small fork at the end. The fork has to go over the pin on the reverse gear lever. Since you have the transmission out you can elevate one end which will help keep the reverse lever in the neutral position.

I used your method to move reverse and it worked.

The main shaft gears are in N, but the reverse gear is engaged. You can see the fork that moves it to the left of the red arrow. There is no detent to hold it in position, so it tends to slide around. Put a dab of wheel bearing grease on the reverse gear shaft to stick it in N position. You can tell if it is in N when you can turn the output shaft and the input shaft/counter shaft does not rotate.

Alternatively, you could put the top cover in R and then isntall it.

Back at it today. I was able to move the reverse gear into neutral, both input and output shafts turn freely now in either direction, the shifter is in neutral so next step was to install the tranny cover, the reverse fork dropped in place with out any issue so did the other two forks, bolted cover down shifter moves left to right however it does not move up and down and cannot shift. I removed the shifter cover the detent balls and springs are properly in their respective wells, lubed gears, forks, and shifter re-installed cover still not able to shift. The reverse shifting mechanism moves freely see pics, however, the other gear mechanisms will not budge, it appears something is preventing up and down (1st to 2nd) movement.

Reverse mechanism moves freely
IMG_20140929_120427.jpg


Reverse mechanism moves freely left to right the other gear mechanisms will not budge
IMG_20140929_120438.jpg


Reverse moved into neutral
IMG_20140929_103835.jpg


Location of gears prior to reinstalling cover (reverse in neutral)
IMG_20140929_103843.jpg
 
The top cover is not in N if you cannot shift it. If the tranny is in N, then the forks are not installed properly either. The slots for the shift cane nose have to line up 3 in a row. The reverse slot has a spring button. No need to fool with the detents and springs. It is like a Chinese puzzle if you take it apart, but the FSM covers how it goes back together.
 
The top cover is not in N if you cannot shift it. If the tranny is in N, then the forks are not installed properly either. The slots for the shift cane nose have to line up 3 in a row. The reverse slot has a spring button. No need to fool with the detents and springs. It is like a Chinese puzzle if you take it apart, but the FSM covers how it goes back together.

The FSM says to have the case cover assembly and gears in neutral position, unfortunately I don't have a frame of reference, I've searched for pics here and on the internet with no results, a pic or two would probably help.
 
I know pictures have been posted here several times. You look inside the shift tower at the slots that the nose of the sift cane sits in and see which one is not aligned. The other way is to push all of the other forks in both directions. Only one will be able to move and after you move it, it will be in neutral.
HTH
 

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