G-50 - Variable Pedal Travel for Clutch Engagement/Disengagement
10-03-2002, 07:57 AM
#1
Burning Brakes
Thread Starter
G-50 - Variable Pedal Travel for Clutch Engagement/Disengagement
G-50 - Variable Pedal Travel for Clutch Engagement/Disengagement
I have an 87 911 (obviously with a G-50) and can not figure out why the "engagement/disengagement point" for the clutch, as measured in pedal travel, changes drastically.
Sometimes the clutch engages and disengages when the clutch pedal is nearly at the floor. When this condition occurs, there is about an inch and a half of free pedal travel that is not under any resistance.
Other times, the entire length of the pedal travel is under resistance, with the "engagement/disengagement point" when the pedal is at a point furthest from the floor.
When I first bought the 911, I (erroneously) thought the "engagement/disengagement" point of the pedal position could be adjusted. I now know that the proper "engagement/disengagement" point of the pedal position is at a point nearly all of the way from the floor.
I have had the clutch master cylinder bled.
Also, once the transmission is heated up (after driving the car a while under conditions requiring multiple gear changes) the "engagement/disengagement" point of the pedal position is at a point nearly all of the way from the floor.
Any insight would be greatly appreciated.
John
I have an 87 911 (obviously with a G-50) and can not figure out why the "engagement/disengagement point" for the clutch, as measured in pedal travel, changes drastically.
Sometimes the clutch engages and disengages when the clutch pedal is nearly at the floor. When this condition occurs, there is about an inch and a half of free pedal travel that is not under any resistance.
Other times, the entire length of the pedal travel is under resistance, with the "engagement/disengagement point" when the pedal is at a point furthest from the floor.
When I first bought the 911, I (erroneously) thought the "engagement/disengagement" point of the pedal position could be adjusted. I now know that the proper "engagement/disengagement" point of the pedal position is at a point nearly all of the way from the floor.
I have had the clutch master cylinder bled.
Also, once the transmission is heated up (after driving the car a while under conditions requiring multiple gear changes) the "engagement/disengagement" point of the pedal position is at a point nearly all of the way from the floor.
Any insight would be greatly appreciated.
John
10-03-2002, 09:49 AM
#2
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Hey John,
I too find that on my '87 Carrera the clutch engages at the furthest point from the floor. I had the clutch replaced 4 years ago (22k miles) and I don't think that it is worn yet because on parking garage exits (steep slopes) the clutch doesn't slip at all. The car is not abused or driven very hard. It would put my mind at ease to know that this is normal.
Ciao,
Alex J.
'87 Carrera Cabriolet
I too find that on my '87 Carrera the clutch engages at the furthest point from the floor. I had the clutch replaced 4 years ago (22k miles) and I don't think that it is worn yet because on parking garage exits (steep slopes) the clutch doesn't slip at all. The car is not abused or driven very hard. It would put my mind at ease to know that this is normal.
Ciao,
Alex J.
'87 Carrera Cabriolet
10-03-2002, 11:03 AM
#3
Rennlist Member
Have you had the transmission update kit put on your cars ? This is a kit that replaces the small roller bearing with a large pin and inserts into a much more "beefier" shifting fork. The bearing may have gone out which changes the position or moves the pin under different loads. This is my my guess since mine did the same thing a couple a years ago.
Spider911
88 Carrera
Spider911
88 Carrera
10-03-2002, 12:51 PM
#4
Burning Brakes
Thread Starter
I have not had the transmission update.
Also, the transmission functions properly under both pedal conditions. Do I have to have it fixed or can I just live with it
With respect to the correct pedal position, the engagement/disengagement point should be furthest from the floor.
John
Also, the transmission functions properly under both pedal conditions. Do I have to have it fixed or can I just live with it
With respect to the correct pedal position, the engagement/disengagement point should be furthest from the floor.
John
10-03-2002, 06:32 PM
#5
Rennlist Member
I would check with a qualified P-mechanic since you will have to pull the engine and tranny. If you can pull it yourself that's OK. The reference points on the pivot point seem to change when the bearing goes out. It will almost always move, but sometimes may stay the same from shift to shift. Since the G50 is hydraulically operated, there is no mechanical hook up such as a cable to interfere or strech. If it is the fork and bearing, the kit costs about $200 and I think you can do it yourself.
Has anyone experienced this that can provide some insight? I had mine done when the engine was out for valve guides. My tranny was experiencing the same symptoms.
Has anyone experienced this that can provide some insight? I had mine done when the engine was out for valve guides. My tranny was experiencing the same symptoms.
10-04-2002, 09:58 AM
#6
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John,
I would check that the 2 screws holding the slave cylinder are tight.
I was in there this spring when I did an unscheduled upgrade of the ring gear and needle bearings on the clutch lever and think that along with loose slave attaching screws, a crack in the lever or needle bearing damage/wear are all possibilities.
With the wheel removed you may be able to remove the rubber boot where the slave rod goes into the housing and with a mirror look at the action when your 'assistant'pushes the pedal.
For good access you may need to lower the transmission in front. Afloor jack is needed for this job but it's basically lo tech.
Email me with any specific questions that you have.
Ned Monaghan
I would check that the 2 screws holding the slave cylinder are tight.
I was in there this spring when I did an unscheduled upgrade of the ring gear and needle bearings on the clutch lever and think that along with loose slave attaching screws, a crack in the lever or needle bearing damage/wear are all possibilities.
With the wheel removed you may be able to remove the rubber boot where the slave rod goes into the housing and with a mirror look at the action when your 'assistant'pushes the pedal.
For good access you may need to lower the transmission in front. Afloor jack is needed for this job but it's basically lo tech.
Email me with any specific questions that you have.
Ned Monaghan
10-06-2002, 03:58 AM
#7
What you guys are seeing is definitely not normal. I would guess as others have mentioned that the shift fork/bearings/mainshaft was having some sort of problem, probably due to the known problem on the G-50's. Porsche originally had a kit that involved boring out the old bearing ear to accept a new updated bearing, but the bushing kit sold by performance products works great and is relatively cheap.
My guess would be that at some point this would turn into a bigger problem.
My guess would be that at some point this would turn into a bigger problem.
