Clutch Pedal Roll Pin Failure (or, the clutch ain't dead yet!)
04-20-2009, 10:13 AM
#16
Great pictures Jamie, I am just about to order the rollpin and bushings and am wondering about getting an aluminum floorboard. Did anybody replace the floorboards with the aluminum ones. Seems logical.
04-20-2009, 10:28 AM
#17
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10-13-2009, 04:21 PM
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Gone again...............
Day off tomorrow, going to replace roll pin, and bushes if in stock at Porsche Byfleet.
Next on the list is the dreaded starter motor, oh, and the n/s window, carrier corroded away, rear bumper/exhaust insulation and the rear spoiler bearing, my god, the noise!!
Don't you just love them....................
Day off tomorrow, going to replace roll pin, and bushes if in stock at Porsche Byfleet.
Next on the list is the dreaded starter motor, oh, and the n/s window, carrier corroded away, rear bumper/exhaust insulation and the rear spoiler bearing, my god, the noise!!
Don't you just love them....................
07-16-2011, 01:08 PM
#19
roll pin
Searched and found this old thread on roll pin replacement. I pulled my pedal cluster out and found the roll pin wasn't damaged, but had worked its way out. I thought about driving it back in and putting some loctite on it, but I think I'm going to replace with an M6 bolt and lock nut. I don't really trust it to stay in there.
07-20-2011, 06:38 PM
#20
Race Car
Rob, just my "two cents" here, a nut/bolt won't work the same as it doesn't put pressure throughout the connection and would likely wear out fairly quickly, possibly enlarging the holes in your factory pedal/shaft as well.
Get a new roll pin, I have one somewhere but moved about a year ago and probably couldn't find it without a MASSIVE search effort in my shop. :P
Don't just pound the old one back in either, use a new one.
Just my "two cents" of course.
Get a new roll pin, I have one somewhere but moved about a year ago and probably couldn't find it without a MASSIVE search effort in my shop. :P
Don't just pound the old one back in either, use a new one.
Just my "two cents" of course.
10-09-2016, 03:34 AM
#21
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Jeff, it's part # N.023.351.1
I just replaced it with an M6 bolt/lock nut.
(Looking back, I wish I replaced the pedal bushings that I had apart......... I lubricated everything, and it felt better for about a month..... brake pedal bushings #999.924.014.40, and clutch pedal bushings # 964.423.611.00, and you need 2 of each type)
I just replaced it with an M6 bolt/lock nut.
(Looking back, I wish I replaced the pedal bushings that I had apart......... I lubricated everything, and it felt better for about a month..... brake pedal bushings #999.924.014.40, and clutch pedal bushings # 964.423.611.00, and you need 2 of each type)
I shut the engine off when I arrived at my garage but immediately I was able to put into the 1st; I noticed for the first time I was able to "pull" the pedal up with my toe. So I restarted the car and the clutch movement seemed to work again. No problem in shifting into 1st again at this time! Prior to the incident, I noticed there was perhaps a .25-.50" play movement on the pedal from the leveled position down until the pedal spring-resistance feel was presence. Has anyone else had similar play on their clutch pedals?
Now that I have read other 964 owners who have experienced the same pedal level drop and it seems to me the infamous clutch roll pin and clutch pedal bushings are the likely culprits, I would like to get the new parts in and start my next weekend project.
For those of you 964 enthusiasts who have done this repair successfully, would you please confirm if the correct parts are as follows?
1 roll pin - N.023.351.1
2 clutch pedal bushings - 964.423.611.00
Asides from our Porsche dealerships, who else may carry these genuine parts? By chance, Pelican Parts? Thanks in advance for any responses, hints and tips on this repair work.
Tony
SF, CA
Last edited by Porsche930; 10-09-2016 at 04:02 AM.
10-10-2016, 09:15 AM
#22
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Hi everyone, I came across this older post while researching for my clutch pedal issue. So basically while test driving my new to me 90 964 after making sure both the AC condenser and oil cooler fans for proper operations, my clutch pedal dropped half way from its normal returned position (i.e. level with the brake pedal). I was panic as I thought the clutch master and/or slave cylinder hydraulic was gone. I could not get into the 1st gear at a stop and I wasn't aware then that the clutch pedal could perhaps be brought up using the top of my toe. All I could do was "forcefully" shifted into 2nd to start from stop and drove the car home that way without using the 1st.
I shut the engine off when I arrived at my garage but immediately I was able to put into the 1st; I noticed for the first time I was able to "pull" the pedal up with my toe. So I restarted the car and the clutch movement seemed to work again. No problem in shifting into 1st again at this time! Prior to the incident, I noticed there was perhaps a .25-.50" play movement on the pedal from the leveled position down until the pedal spring-resistance feel was presence. Has anyone else had similar play on their clutch pedals?
Now that I have read other 964 owners who have experienced the same pedal level drop and it seems to me the infamous clutch roll pin and clutch pedal bushings are the likely culprits, I would like to get the new parts in and start my next weekend project.
For those of you 964 enthusiasts who have done this repair successfully, would you please confirm if the correct parts are as follows?
1 roll pin - N.023.351.1
2 clutch pedal bushings - 964.423.611.00
Asides from our Porsche dealerships, who else may carry these genuine parts? By chance, Pelican Parts? Thanks in advance for any responses, hints and tips on this repair work.
Tony
SF, CA
I shut the engine off when I arrived at my garage but immediately I was able to put into the 1st; I noticed for the first time I was able to "pull" the pedal up with my toe. So I restarted the car and the clutch movement seemed to work again. No problem in shifting into 1st again at this time! Prior to the incident, I noticed there was perhaps a .25-.50" play movement on the pedal from the leveled position down until the pedal spring-resistance feel was presence. Has anyone else had similar play on their clutch pedals?
Now that I have read other 964 owners who have experienced the same pedal level drop and it seems to me the infamous clutch roll pin and clutch pedal bushings are the likely culprits, I would like to get the new parts in and start my next weekend project.
For those of you 964 enthusiasts who have done this repair successfully, would you please confirm if the correct parts are as follows?
1 roll pin - N.023.351.1
2 clutch pedal bushings - 964.423.611.00
Asides from our Porsche dealerships, who else may carry these genuine parts? By chance, Pelican Parts? Thanks in advance for any responses, hints and tips on this repair work.
Tony
SF, CA
10-10-2016, 09:48 AM
#23
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Broke one of those at Daytona in '98 at the 24hr, one of my mechanics ripped out the floorboard and was drilling out the mangled pin while I watched laps go by. I pulled him out, reached down with a hammer and broke off the drill bit that was well into the hole. It lasted the rest of the race
10-10-2016, 10:05 AM
#24
Race Car
The typical reason for breaking a roll pin is mis adjustment of the clutch pedal stop on the floor board. The pedal stop has to stop the pedal. If you allow the master cylinder to be the pedal stop, the shear force on the brittle pin is too high.
This is why I switched to a 993 pedal box. The design is more robust. The kinematic lever is on a splined shaft rather than held by a pin, and the bushings are thin and metal. Over all you get significantly better pedal feel and it never fails. If I ever figure out the clutch return issue I'll be using it again.
This is why I switched to a 993 pedal box. The design is more robust. The kinematic lever is on a splined shaft rather than held by a pin, and the bushings are thin and metal. Over all you get significantly better pedal feel and it never fails. If I ever figure out the clutch return issue I'll be using it again.
10-10-2016, 10:57 AM
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Thanks for posting your reply Rob! It looks like the clutch pedal has been back to its normal position for the last couple of days of driving with no issue. I will still order the parts and get on it on one of the weekends though.
10-10-2016, 10:59 AM
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Broke one of those at Daytona in '98 at the 24hr, one of my mechanics ripped out the floorboard and was drilling out the mangled pin while I watched laps go by. I pulled him out, reached down with a hammer and broke off the drill bit that was well into the hole. It lasted the rest of the race
I prefer a more permanent approach to get this fixed once and for all
10-10-2016, 11:02 AM
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The typical reason for breaking a roll pin is mis adjustment of the clutch pedal stop on the floor board. The pedal stop has to stop the pedal. If you allow the master cylinder to be the pedal stop, the shear force on the brittle pin is too high.
This is why I switched to a 993 pedal box. The design is more robust. The kinematic lever is on a splined shaft rather than held by a pin, and the bushings are thin and metal. Over all you get significantly better pedal feel and it never fails. If I ever figure out the clutch return issue I'll be using it again.
This is why I switched to a 993 pedal box. The design is more robust. The kinematic lever is on a splined shaft rather than held by a pin, and the bushings are thin and metal. Over all you get significantly better pedal feel and it never fails. If I ever figure out the clutch return issue I'll be using it again.
10-10-2016, 11:44 AM
#28
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The typical reason for breaking a roll pin is mis adjustment of the clutch pedal stop on the floor board. The pedal stop has to stop the pedal. If you allow the master cylinder to be the pedal stop, the shear force on the brittle pin is too high.
This is why I switched to a 993 pedal box. The design is more robust. The kinematic lever is on a splined shaft rather than held by a pin, and the bushings are thin and metal. Over all you get significantly better pedal feel and it never fails. If I ever figure out the clutch return issue I'll be using it again.
This is why I switched to a 993 pedal box. The design is more robust. The kinematic lever is on a splined shaft rather than held by a pin, and the bushings are thin and metal. Over all you get significantly better pedal feel and it never fails. If I ever figure out the clutch return issue I'll be using it again.
10-10-2016, 12:04 PM
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10-10-2016, 07:16 PM
#30
Race Car
I wrote it up in post 502 on the suspension madness thread...but looks like I didn't post pics of the rebuild...sorry abt that. I'll look to see if I have any pics and post them if I do. Otherwise I'll try to take some new ones and show what I can...
As to ease of swap, it takes 10 mins to take out a 964 pedal box and install a 993 pedal box. Literally bolt out bolt in. I have the box and an updated kinematic lever for sale for 700...I never got to the end of the clutch return issue...but that updated kinematic lever is apparently the fix. I still think that pedal box was the best upgrade I made. Just need to work on other people's cars at the moment and not mine, so happy to send mine to someone who will appreciate it. Virtually all the parts in mine are new. So it's a bolt in replacement with no headaches. Clutch returns fine to the last 2cm. And then waits for the pressure bomb to start up to return the last 2cm. Has no affect on clutch engagement so I've been using it like that for the past year.
Rob- the difference in parts are the shaft for the clutch itself is twice as thick and ends with a spline that the kinematic lever presses into. No more broken rollpin - ever. The bushings are metal. So no vibration dampening, which allows for better road feel. And the pedal arms themselves are a bit heavier, so more direct feeling when on the brakes hard. I.e. No flex in the pedal arm. The big difference is the kinematic level has longer arms, so you have significantly more leverage on the clutch pedal and therefore the pedal is lighter by a mile. So traffic is easier to deal with and interestingly enough, when you don't have to press so hard on the clutch, to my feet, it feels as though I have more control over the brake pedal, since one leg isn't using so much more pressure than the other, it all feels more in balance.
As to ease of swap, it takes 10 mins to take out a 964 pedal box and install a 993 pedal box. Literally bolt out bolt in. I have the box and an updated kinematic lever for sale for 700...I never got to the end of the clutch return issue...but that updated kinematic lever is apparently the fix. I still think that pedal box was the best upgrade I made. Just need to work on other people's cars at the moment and not mine, so happy to send mine to someone who will appreciate it. Virtually all the parts in mine are new. So it's a bolt in replacement with no headaches. Clutch returns fine to the last 2cm. And then waits for the pressure bomb to start up to return the last 2cm. Has no affect on clutch engagement so I've been using it like that for the past year.
Rob- the difference in parts are the shaft for the clutch itself is twice as thick and ends with a spline that the kinematic lever presses into. No more broken rollpin - ever. The bushings are metal. So no vibration dampening, which allows for better road feel. And the pedal arms themselves are a bit heavier, so more direct feeling when on the brakes hard. I.e. No flex in the pedal arm. The big difference is the kinematic level has longer arms, so you have significantly more leverage on the clutch pedal and therefore the pedal is lighter by a mile. So traffic is easier to deal with and interestingly enough, when you don't have to press so hard on the clutch, to my feet, it feels as though I have more control over the brake pedal, since one leg isn't using so much more pressure than the other, it all feels more in balance.