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Wew
Hi all,
I did a Dr. Evil transmission rebuild a couple years ago and also put a new flywheel, clutch disc and pressure plate along with a new clutch cable.
Drove the car about 20 miles and everything worked well. A little tough getting it into first but I think I could have adjusted the clutch and addressed that.
Engine was rebuilt, by your truly and was leaking oil so I dropped the motor several times 3x to track down the leak. Pulled heads and piston cylinders and found one of my problems with piston oil ring missing one of two rings that sandwiches the waffle ring.
Fixed problem, albeit 2 years later and engine and transmission are ready for install again.
Now the transmission and clutch are not behaving. Tighten clutch cable and depress clutch pedal to go through gears and it’s like the clutch is not working. I take my foot off the clutch and can still push through the gears with no noticeable difference in the feel or movement. Now I haven’t lined up the shifter to be spot on however there is no difference between clutch pedal pushed all the way down or the cable totally disconnected.
I look at the shift fork and it seems to be frozen or no play.
I remove transmission and clutch and inspect. When I did the trans rebuild I also got the new fork bracket and plastic bushing and whatever else could be replaced. Of course a new throw out bearing as well.
Move fork back and forth everything moves nicely, maybe my flywheel, clutch disc nipple out, facing towards the rear of the car, and pressure plate (pressure plate fingers had some markings on them) weren’t lined up perfectly. I used the plastic alignment tool again and make sure everything is straight on. Put some swepco grease on the nose and spline of the transmission shaft and up she goes back onto the car.
Everything lines up nicely and slide back in without to much trouble.
The clutch fork rests against the housing towards the front of the car and has about a 1/2” of play towards the back.
Cable back on and tightened and no difference. When clutch pedal is depressed the fork moves, but there is no difference in the feel. Role pin is in place.
I have also put a camera in the center tunnel and cables are routed properly and the brackets for the cable guide tubes are in place.
Where have I gone astray headbang.gif chair.gif confused24.gif
Robarabian
Are you testing this on a running engine or just depressing the clutch with it all installed and not running. I don't think the clutch is doing much if it is stationary, it needs to be running to know if it is working.

Someone else chime in here, but you can't even really adjust things until it is spinning.



QUOTE(Wew @ Feb 16 2023, 07:33 PM) *

Hi all,
I did a Dr. Evil transmission rebuild a couple years ago and also put a new flywheel, clutch disc and pressure plate along with a new clutch cable.
Drove the car about 20 miles and everything worked well. A little tough getting it into first but I think I could have adjusted the clutch and addressed that.
Engine was rebuilt, by your truly and was leaking oil so I dropped the motor several times 3x to track down the leak. Pulled heads and piston cylinders and found one of my problems with piston oil ring missing one of two rings that sandwiches the waffle ring.
Fixed problem, albeit 2 years later and engine and transmission are ready for install again.
Now the transmission and clutch are not behaving. Tighten clutch cable and depress clutch pedal to go through gears and it’s like the clutch is not working. I take my foot off the clutch and can still push through the gears with no noticeable difference in the feel or movement. Now I haven’t lined up the shifter to be spot on however there is no difference between clutch pedal pushed all the way down or the cable totally disconnected.
I look at the shift fork and it seems to be frozen or no play.
I remove transmission and clutch and inspect. When I did the trans rebuild I also got the new fork bracket and plastic bushing and whatever else could be replaced. Of course a new throw out bearing as well.
Move fork back and forth everything moves nicely, maybe my flywheel, clutch disc nipple out, facing towards the rear of the car, and pressure plate weren’t lined up perfectly. I used the plastic alignment tool again and make sure everything is straight on. Put some swepco grease on the nose and spline of the transmission shaft and up she goes back onto the car.
Everything lines up nicely and slide back in without to much trouble.
The clutch fork rests against the housing towards the front of the car and has about a 1/2” of play towards the back.
Cable back on and tightened and no difference. When clutch pedal is depressed the fork moves, but there is no difference in the feel. Role pin is in place.
I have also put a camera in the center tunnel and cables are routed properly and the brackets for the cable guide tubes are in place.
Where have I gone astray headbang.gif chair.gif confused24.gif

Wew
Hi Robar,
I am depressing the clutch on a non running car.
I am keeping my fingers crossed it could be that simple.
Thank you for the input.
With all the challenges I have had with this build, I assume the worse when something is t working just so.
Again thank you for weighing in.
Gary
Jack Standz
" Tighten clutch cable and depress clutch pedal to go through gears and it’s like the clutch is not working."

Not sure what you mean, but this language makes it seem like the clutch is not disengaging when you depress the clutch pedal?

Did you replace the small plastic bushing on the back of the clutch fork? If it's worn too much, the clutch won't disengage.

Is it a new or newly machined flywheel? If it's a newly machined flywheel, the ball/bolt the above plastic bushing rides on can be too far away for the fork to operate properly. The fix is to put a right-sized spacer (with sealant so,the transmission oil doesn't leak out) under the ball/bolt. Also, if the flywheel machining is really messed up, you'll never get there and will need a new flywheel, so measure it.
Wew
Hi Jack,
Yes, clutch feels like it’s not disengaging. Thank you for clarification
I did replace the small plastic bushing on back of the fork.
It’s a new flywheel.
The fork does have that play in it before I attach the clutch cable.

Appreciate the input and any further
I used swepco transmission fluid in case that matters.

Thanks,

Gary
Wew
QUOTE(Jack Standz @ Feb 17 2023, 08:34 AM) *

" Tighten clutch cable and depress clutch pedal to go through gears and it’s like the clutch is not working."

Not sure what you mean, but this language makes it seem like the clutch is not disengaging when you depress the clutch pedal?

Did you replace the small plastic bushing on the back of the clutch fork? If it's worn too much, the clutch won't disengage.

Is it a new or newly machined flywheel? If it's a newly machined flywheel, the ball/bolt the above plastic bushing rides on can be too far away for the fork to operate properly. The fix is to put a right-sized spacer (with sealant so,the transmission oil doesn't leak out) under the ball/bolt. Also, if the flywheel machining is really messed up, you'll never get there and will need a new flywheel, so measure it.

Wew
This is a picture of the fork in the transmission. The shiny object if you expand it is the space of the fork connected to the nipple.
Jack Standz
Some more guesses:

clutch cable not properly adjusted (depressing the pedal needs to do more than just make the fork move, it needs to move far enough to disengage the clutch)

Oil leaks you mentioned (especially if from the rear main seal) caused the clutch material to swell?

Best wishes for getting her fixed!
dr914@autoatlanta.com
maybe during the down time, the clutch disc glued itself to the pressure plate?

QUOTE(Wew @ Feb 16 2023, 08:33 PM) *

Hi all,
I did a Dr. Evil transmission rebuild a couple years ago and also put a new flywheel, clutch disc and pressure plate along with a new clutch cable.
Drove the car about 20 miles and everything worked well. A little tough getting it into first but I think I could have adjusted the clutch and addressed that.
Engine was rebuilt, by your truly and was leaking oil so I dropped the motor several times 3x to track down the leak. Pulled heads and piston cylinders and found one of my problems with piston oil ring missing one of two rings that sandwiches the waffle ring.
Fixed problem, albeit 2 years later and engine and transmission are ready for install again.
Now the transmission and clutch are not behaving. Tighten clutch cable and depress clutch pedal to go through gears and it’s like the clutch is not working. I take my foot off the clutch and can still push through the gears with no noticeable difference in the feel or movement. Now I haven’t lined up the shifter to be spot on however there is no difference between clutch pedal pushed all the way down or the cable totally disconnected.
I look at the shift fork and it seems to be frozen or no play.
I remove transmission and clutch and inspect. When I did the trans rebuild I also got the new fork bracket and plastic bushing and whatever else could be replaced. Of course a new throw out bearing as well.
Move fork back and forth everything moves nicely, maybe my flywheel, clutch disc nipple out, facing towards the rear of the car, and pressure plate (pressure plate fingers had some markings on them) weren’t lined up perfectly. I used the plastic alignment tool again and make sure everything is straight on. Put some swepco grease on the nose and spline of the transmission shaft and up she goes back onto the car.
Everything lines up nicely and slide back in without to much trouble.
The clutch fork rests against the housing towards the front of the car and has about a 1/2” of play towards the back.
Cable back on and tightened and no difference. When clutch pedal is depressed the fork moves, but there is no difference in the feel. Role pin is in place.
I have also put a camera in the center tunnel and cables are routed properly and the brackets for the cable guide tubes are in place.
Where have I gone astray headbang.gif chair.gif confused24.gif

Steve
The clutch fork should be around half way in the opening when touching the pressure plate. If its not, then you need to adjust the pivot ball. Putting a washer behind it will move the pivot closer to the pressure plate. When depressing the clutch are you hitting the rear of the opening? You should have roughly a 1/2" free play pulling the clutch pedal towards you by hand and back. When engaging the clutch the fork should not hit the rear of the opening on the trans.
Wew
Thanks gents. The oil leak didn’t impact clutch transmission area.
I am tightening the clutch cable more but the dang thing feels pretty darn hard to depress now and there is zero play in the pedal.
Wew
After reading Steve’s post I think I need to pull the transmission and adjust or put a washer behind the pivot ball.
Wew
After reading Steve’s post I think I need to pull the transmission and adjust or put a washer behind the pivot ball.
I adjusted cable and now have the 1/2” free play.
I am including a couple of pictures that show the position of the fork after adjustment and it seems to fit nicely in the center of the opening. I also took another pic of the inside that shows the distance of the pivot ball from the fork.
Wew
Attached are the photos
Click to view attachment
Click to view attachment
Wew
Maybe my clutch disc is backwards? Can’t think of anything else. Well gonna drop the tranny again and confirm things are in order.
Thanks for the input as always. Much appreciated.
914werke
So think of the mechanics of the process.
Push pedal, which pulls cable, levering arm on fixed pivot, which holds throw out bearing against pressure plate fingers, releasing friction disc.
There are various consideration in terms of assembly. Yes the Friction disc is asymmetrical & must be installed the correct way, Is the arm secured on the pivot ball with the small fork & not sitting on top of the ball? Are the friction blocks installed on the TO bearing? W/O the cable secured to the arm how much back forth play is present ?
It is usual & normal to need to "shim" the pivot ball further out AFTER cutting a existing FW. For a NEW FW it should not be necessary.
Wew
Some pics after transmission drop
Click to view attachment
Click to view attachment
Click to view attachment
Click to view attachment
Wew
Looks like clutch disc was on properly.
Throw out bearing has some nice little gashes on it. Not sure what that is from or what in my adjustment would cause that?
Any clues are appreciated.

Thanks again,

Gary
Wew
Thanks for the input Rich.
I don’t think my plastic bushing and ball we pressed all the way in. Had to give the fork a wack with a piece of wood and rubber mallet then it popped in. I am hoping that was my problem. Can’t figure what else it would be.
Going to begin re install here shortly. Will report back on results.
That is for all the input.

Gary
theer
The wear marks on the pressure plate fingers look pretty deep, too. Might just be the angle of the photo, but the splines on the clutch disc look weird.

But, to your original question… if the car is not running, pushing the clutch in or not doesn’t affect shifting. You said you can row through the gears with the clutch engaged (pedal up) and pushing the pedal down makes no difference. That is exactly what I would expect. If the car rolls in gear with the clutch pedal down, all is as it should be.

There is a non-zero possibility I have completely misunderstood your question, though!!
Geezer914
With the car sitting, and the engine not running, you can go through the gears with the clutch engaged. Put everything back together, adjust the clutch to have 1/2 inch Freeplay at the pedal. Start the car and see if it moves when letting out the clutch.
914werke
QUOTE(Wew @ Feb 17 2023, 02:03 PM) *
I don’t think my plastic bushing and ball we pressed all the way in. Had to give the fork a wack with a piece of wood and rubber mallet then it popped in.

So Im hoping you were refering to the .5 sphere bushing in the arm & not the pivot?
The pivot (ball) is threaded into the trans case & is a through bolt IE if loose stripped or otherwise buggered you will have a leak & a mess.
It must be R&R'ed to shim the arm up when youve cut your FW down.

idea.gif
Wew
Transmission and clutch back in. Off to a social gathering. My mind will be on the 914 with fingers crossed. Hoping all is good from here on out, or least for this chapter in the 914 odyssey! beer.gif beerchug.gif
Wew
QUOTE(914werke @ Feb 17 2023, 03:35 PM) *

QUOTE(Wew @ Feb 17 2023, 02:03 PM) *
I don’t think my plastic bushing and ball we pressed all the way in. Had to give the fork a wack with a piece of wood and rubber mallet then it popped in.

So Im hoping you were refering to the .5 sphere bushing in the arm & not the pivot?
The pivot (ball) is threaded into the trans case & is a through bolt IE if loose stripped or otherwise buggered you will have a leak & a mess.
It must be R&R'ed to shim the arm up when youve cut your FW down.

idea.gif

That is correct Rich. I tapped it and it popped on the sphere.

Thanks for following.

Gary
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