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Bruce Hinds
I reinstalled the engine after a rebuild and for some reason that I can't figure out the clutch seems to go out of adjustment when the car warms up.

I park it and let it cool, the clutch works just fine. Pedal play and everything is normal until it warms up again. Seems to be a bit more play but when warm I can't get first or reverse with grinding. Starting in gear with the clutch in, the car still moves.

How can this be?
914Sixer
Did you replace the clutch fork pivot bushing and release bearing spacers?
bdstone914
Did you connect the ground strap from thr trans to body? If not the clutch cable acts as a ground for the engine.
Also check for clutch tube attachment in the tunnel. Remove the shifter bolts and push the shifter to the passenger side. Depress the clutch and see if the tube moves.
Bruce Hinds
QUOTE(914Sixer @ Dec 31 2022, 07:08 AM) *

Did you replace the clutch fork pivot bushing and release bearing spacers?


I did not. How would that be affected by heat or cold?
Bruce Hinds
QUOTE(bdstone914 @ Dec 31 2022, 07:38 AM) *

Did you connect the ground strap from thr trans to body? If not the clutch cable acts as a ground for the engine.
Also check for clutch tube attachment in the tunnel. Remove the shifter bolts and push the shifter to the passenger side. Depress the clutch and see if the tube moves.


The ground strap is in place and the tube is secure. It had broken loose many years ago and I made a firewall fix as well as a fix in the tunnel to secure it. Again, not sure how heat would cause this to change. I also replaced the cable with a new one.
914Sixer
Bushing tends to crumble under heat. I do not know personally but I have heard the new clutch cables are not what they used to be. Perhaps some stretching is starting to take place.
bdstone914
QUOTE(Bruce Hinds @ Dec 31 2022, 10:13 AM) *

QUOTE(bdstone914 @ Dec 31 2022, 07:38 AM) *

Did you connect the ground strap from thr trans to body? If not the clutch cable acts as a ground for the engine.
Also check for clutch tube attachment in the tunnel. Remove the shifter bolts and push the shifter to the passenger side. Depress the clutch and see if the tube moves.


The ground strap is in place and the tube is secure. It had broken loose many years ago and I made a firewall fix as well as a fix in the tunnel to secure it. Again, not sure how heat would cause this to change. I also replaced the cable with a new one.



What brand cable did you use? I have heard of problems with Terry cables? Was it wirking with the old cable? Still have it?
Bruce Hinds
QUOTE(914Sixer @ Dec 31 2022, 08:33 AM) *

Bushing tends to crumble under heat. I do not know personally but I have heard the new clutch cables are not what they used to be. Perhaps some stretching is starting to take place.


But here again, I go out the next day to do the adjustment and it's fine, shifts like butter. 10-15 miles down the road its "like" the cable stretched, but wait a few hours and it's fine.

The old cable didn't have too many miles on it but replaced it anyway. I got the one from 914 Rubber, made by GEMO. That doesn't appear to be the problem though,
Bruce Hinds
QUOTE(bdstone914 @ Dec 31 2022, 08:33 AM) *

QUOTE(Bruce Hinds @ Dec 31 2022, 10:13 AM) *

QUOTE(bdstone914 @ Dec 31 2022, 07:38 AM) *

Did you connect the ground strap from thr trans to body? If not the clutch cable acts as a ground for the engine.
Also check for clutch tube attachment in the tunnel. Remove the shifter bolts and push the shifter to the passenger side. Depress the clutch and see if the tube moves.


The ground strap is in place and the tube is secure. It had broken loose many years ago and I made a firewall fix as well as a fix in the tunnel to secure it. Again, not sure how heat would cause this to change. I also replaced the cable with a new one.



What brand cable did you use? I have heard of problems with Terry cables? Was it wirking with the old cable? Still have it?

Yes, replace it with the GEMO cable from 914 rubber. But a few hours after driving it, it works fine. I'm sure if it stretched, it wouldn't un-stretch - right?
Superhawk996
QUOTE(Bruce Hinds @ Dec 31 2022, 12:27 PM) *

QUOTE(914Sixer @ Dec 31 2022, 08:33 AM) *

Bushing tends to crumble under heat. I do not know personally but I have heard the new clutch cables are not what they used to be. Perhaps some stretching is starting to take place.


But here again, I go out the next day to do the adjustment and it's fine, shifts like butter. 10-15 miles down the road its "like" the cable stretched, but wait a few hours and it's fine.

The old cable didn't have too many miles on it but replaced it anyway. I got the one from 914 Rubber, made by GEMO. That doesn't appear to be the problem though,

Sounds an awful like you’re right in the cusp of not having it adjusted tight enough. When clutch, pressure plate, and linkages and cable get warm it becomes no-go situation until things cool a bit.

Have you tried tightening the cable more?? There is a lot of room between just barely working (as you describe) and it being so tight that you’re preloading the throw out bearing, partially loading the the pressure plate and beginning to slip the clutch

The other thing is to make sure the stop bumper on the plywood floor board isn’t preventing you from getting full clutch pedal travel.

The other thing to consider is that shifting ease will change based on the temp of the gear oil in your trans. When oil gets hot, and things expand, the synchros become less effective. I’d tighten the cable more. If the issue continues and you’re convinced you have the linkage adjusted properly, it may be time to consider looking in the transaxle at synchros.

If it was perfect before the cable swap and then went to stromberg.gif then focus on the cable adjustment and disregard the synchros.
Bruce Hinds
QUOTE(Superhawk996 @ Dec 31 2022, 10:30 AM) *

QUOTE(Bruce Hinds @ Dec 31 2022, 12:27 PM) *

QUOTE(914Sixer @ Dec 31 2022, 08:33 AM) *

Bushing tends to crumble under heat. I do not know personally but I have heard the new clutch cables are not what they used to be. Perhaps some stretching is starting to take place.


But here again, I go out the next day to do the adjustment and it's fine, shifts like butter. 10-15 miles down the road its "like" the cable stretched, but wait a few hours and it's fine.

The old cable didn't have too many miles on it but replaced it anyway. I got the one from 914 Rubber, made by GEMO. That doesn't appear to be the problem though,

Sounds an awful like you’re right in the cusp of not having it adjusted tight enough. When clutch, pressure plate, and linkages and cable get warm it becomes no-go situation until things cool a bit.

Have you tried tightening the cable more?? There is a lot of room between just barely working (as you describe) and it being so tight that you’re preloading the throw out bearing, partially loading the the pressure plate and beginning to slip the clutch

The other thing is to make sure the stop bumper on the plywood floor board isn’t preventing you from getting full clutch pedal travel.

The other thing to consider is that shifting ease will change based on the temp of the gear oil in your trans. When oil gets hot, and things expand, the synchros become less effective. I’d tighten the cable more. If the issue continues and you’re convinced you have the linkage adjusted properly, it may be time to consider looking in the transaxle at synchros.

If it was perfect before the cable swap and then went to stromberg.gif then focus on the cable adjustment and disregard the synchros.


It was perfect before the engine rebuild, BUT even though the tranny had a recent rebuild prior to being parked. It had been parked for 14 years in the garage. I'm embarrassed to admit, I've not changed the gear oil, my reasoning that warmer oil should shift easier not harder. I have adjusted the clutch tighter a few times, my next step is to change out the oil, almost afraid to see what comes out if that's the problem.

Superhawk996
QUOTE(Bruce Hinds @ Dec 31 2022, 01:50 PM) *


It was perfect before the engine rebuild, BUT even though the tranny had a recent rebuild prior to being parked. It had been parked for 14 years in the garage. I'm embarrassed to admit, I've not changed the gear oil, my reasoning that warmer oil should shift easier not harder. I have adjusted the clutch tighter a few times, my next step is to change out the oil, almost afraid to see what comes out if that's the problem.


Don’t underestimate cable stretch and thermal expansion of a long cable. Some of the clutch cables out there will virtually run out of adjustment thread before they are tight enough. Not uncommon to need a spacer to get it to adjust properly.

With respect to the ground strap - make sure you have a ZERO ohm connection. A bad ground will use the starter clutch cable to draw starter current (up to hundred or more amps) through it. This occurs right as you have the clutch pushed in when starting. The cable heats up and stretches as all that current flow through it. Likewise the heat cycling of the clutch cable being used as a ground eventually causes it to become brittle and snap.

A ground that looks good may not actually be good. Many of these braided ground straps are 50 years old and need to be replaced to get a solid ZERO ohm ground between the body and the engine/starter.

I agree though that the ground strap is a long shot since yours seems to recover when it cools. Posted more for the benefit of others that may not understand how a bad ground strap causes cable stretch.
Bruce Hinds
QUOTE(Superhawk996 @ Dec 31 2022, 11:04 AM) *

QUOTE(Bruce Hinds @ Dec 31 2022, 01:50 PM) *


It was perfect before the engine rebuild, BUT even though the tranny had a recent rebuild prior to being parked. It had been parked for 14 years in the garage. I'm embarrassed to admit, I've not changed the gear oil, my reasoning that warmer oil should shift easier not harder. I have adjusted the clutch tighter a few times, my next step is to change out the oil, almost afraid to see what comes out if that's the problem.


Don’t underestimate cable stretch and thermal expansion of a long cable. Some of the clutch cables out there will virtually run out of adjustment thread before they are tight enough. Not uncommon to need a spacer to get it to adjust properly.

With respect to the ground strap - make sure you have a ZERO ohm connection. A bad ground will use the starter cable to draw starter current (up to hundred or more amps) through it. This occurs right as you have the clutch pushed in when starting. The cable heats up and stretches as all that current flow through it. Likewise the heat cycling of the clutch cable being used as a ground eventually causes it to become brittle and snap.

A ground that looks good may not actually be good. Many of these braided ground straps are 50 years old and need to be replaced to get a solid ZERO ohm ground between the body and the engine/starter.

I agree though that the ground strap is a long shot since yours seems to recover when it cools. Posted more for the benefit of others that may not understand how a bad ground strap causes cable stretch.


Thanks for the conversation Peter - actually went to HS in Greenlawn, NY with a guy of the same name.
mgphoto
Could be loose motor mounts, it’s not the warm up, the engine and transmission move backwards when going up hill shortening the cable and down hill lengthening it, place a jack under the motor/ transmission and put upward pressure on the assembly, check the torque of mounting bolts.
clarkcou


Thanks for the conversation Peter - actually went to HS in Greenlawn, NY with a guy of the same name.
[/quote]

That would be Harborfields HS.
I was Class of 1973
Randy
izaporsche
QUOTE(Bruce Hinds @ Dec 30 2022, 10:20 PM) *

I reinstalled the engine after a rebuild and for some reason that I can't figure out the clutch seems to go out of adjustment when the car warms up.

I park it and let it cool, the clutch works just fine. Pedal play and everything is normal until it warms up again. Seems to be a bit more play but when warm I can't get first or reverse with grinding. Starting in gear with the clutch in, the car still moves.

How can this be?

Hi Bruce,
I am new to this forum, but felt compelled to add my two cents, it’s your pilot bearing. I went through the same thing , replacing clutch cables and clutch disc/pressure plate, making adjustments after every short drive because it became to difficult to shift into gear and nothing seem to help until I finally replaced my pilot bearing problem solved. Rule of thumb is to always replace you pilot bearing whenever you replace your clutch. My Symptoms were exactly like yours. To all of 914 owners out there happy new year, I’ve been on this sight roaming for a long time...great place to read and learn about this funny lookin but beautiful car that I have loved most of my adult life.

Tony
Bruce Hinds
QUOTE(izaporsche @ Jan 2 2023, 05:51 AM) *

QUOTE(Bruce Hinds @ Dec 30 2022, 10:20 PM) *

I reinstalled the engine after a rebuild and for some reason that I can't figure out the clutch seems to go out of adjustment when the car warms up.

I park it and let it cool, the clutch works just fine. Pedal play and everything is normal until it warms up again. Seems to be a bit more play but when warm I can't get first or reverse with grinding. Starting in gear with the clutch in, the car still moves.

How can this be?

Hi Bruce,
I am new to this forum, but felt compelled to add my two cents, it’s your pilot bearing. I went through the same thing , replacing clutch cables and clutch disc/pressure plate, making adjustments after every short drive because it became to difficult to shift into gear and nothing seem to help until I finally replaced my pilot bearing problem solved. Rule of thumb is to always replace you pilot bearing whenever you replace your clutch. My Symptoms were exactly like yours. To all of 914 owners out there happy new year, I’ve been on this sight roaming for a long time...great place to read and learn about this funny lookin but beautiful car that I have loved most of my adult life.

Tony


Hi Tony, welcome to the group. I used to be a lot more active, something happened a few years back where we no longer receive emails when a post is responded to . . . so checking back to get answers is necessary. But I miss a lot of conversations now.

I had heard about the pilot bearing from another source but discounted the idea since I did put a new one in and made sure it was lubed. Perhaps I didn't get the pilot all the way in . . . I was hoping to find an easier solution than going back in there.
izaporsche
QUOTE(Bruce Hinds @ Jan 2 2023, 11:43 AM) *

QUOTE(izaporsche @ Jan 2 2023, 05:51 AM) *

QUOTE(Bruce Hinds @ Dec 30 2022, 10:20 PM) *

I reinstalled the engine after a rebuild and for some reason that I can't figure out the clutch seems to go out of adjustment when the car warms up.

I park it and let it cool, the clutch works just fine. Pedal play and everything is normal until it warms up again. Seems to be a bit more play but when warm I can't get first or reverse with grinding. Starting in gear with the clutch in, the car still moves.

How can this be?

Hi Bruce,
I am new to this forum, but felt compelled to add my two cents, it’s your pilot bearing. I went through the same thing , replacing clutch cables and clutch disc/pressure plate, making adjustments after every short drive because it became to difficult to shift into gear and nothing seem to help until I finally replaced my pilot bearing problem solved. Rule of thumb is to always replace you pilot bearing whenever you replace your clutch. My Symptoms were exactly like yours. To all of 914 owners out there happy new year, I’ve been on this sight roaming for a long time...great place to read and learn about this funny lookin but beautiful car that I have loved most of my adult life.

Tony


Hi Tony, welcome to the group. I used to be a lot more active, something happened a few years back where we no longer receive emails when a post is responded to . . . so checking back to get answers is necessary. But I miss a lot of conversations now.

I had heard about the pilot bearing from another source but discounted the idea since I did put a new one in and made sure it was lubed. Perhaps I didn't get the pilot all the way in . . . I was hoping to find an easier solution than going back in there.


Hi Bruce, I replaced my clutch twice thinking that the pressure plate was faulty and the clutch cable once thinking that was the problem, but never thought of replacing the pilot bearing because it felt fine spinning and not binding and was well greased, I think what was happening was the temp going up due to friction causing the bearings to siege up and make it hard to put the car into gear, finally decided to replace the pilot bearing and all is good...after removing the transaxle a couple of times it’s a breeze, approximately 1hr each time..
Bruce Hinds
QUOTE(izaporsche @ Jan 2 2023, 05:20 PM) *

QUOTE(Bruce Hinds @ Jan 2 2023, 11:43 AM) *

QUOTE(izaporsche @ Jan 2 2023, 05:51 AM) *

QUOTE(Bruce Hinds @ Dec 30 2022, 10:20 PM) *

I reinstalled the engine after a rebuild and for some reason that I can't figure out the clutch seems to go out of adjustment when the car warms up.

I park it and let it cool, the clutch works just fine. Pedal play and everything is normal until it warms up again. Seems to be a bit more play but when warm I can't get first or reverse with grinding. Starting in gear with the clutch in, the car still moves.

How can this be?

Hi Bruce,
I am new to this forum, but felt compelled to add my two cents, it’s your pilot bearing. I went through the same thing , replacing clutch cables and clutch disc/pressure plate, making adjustments after every short drive because it became to difficult to shift into gear and nothing seem to help until I finally replaced my pilot bearing problem solved. Rule of thumb is to always replace you pilot bearing whenever you replace your clutch. My Symptoms were exactly like yours. To all of 914 owners out there happy new year, I’ve been on this sight roaming for a long time...great place to read and learn about this funny lookin but beautiful car that I have loved most of my adult life.

Tony


Hi Tony, welcome to the group. I used to be a lot more active, something happened a few years back where we no longer receive emails when a post is responded to . . . so checking back to get answers is necessary. But I miss a lot of conversations now.

I had heard about the pilot bearing from another source but discounted the idea since I did put a new one in and made sure it was lubed. Perhaps I didn't get the pilot all the way in . . . I was hoping to find an easier solution than going back in there.


Hi Bruce, I replaced my clutch twice thinking that the pressure plate was faulty and the clutch cable once thinking that was the problem, but never thought of replacing the pilot bearing because it felt fine spinning and not binding and was well greased, I think what was happening was the temp going up due to friction causing the bearings to siege up and make it hard to put the car into gear, finally decided to replace the pilot bearing and all is good...after removing the transaxle a couple of times it’s a breeze, approximately 1hr each time..


An hour each time - Come on over and give me a hand will ya?!?!?!?
I think I spent more time than that just trying to get the old one out of the crank while the engine out of the car. I envision the transaxle coming out, I'll go in in it's place and get really frustrated. Then the hard part, getting the tranny to slide back in. Sometimes, it seems easier just pulling the engine and trans on a dollly when you don't have a lift.
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