? air in the clutch lines ?
11-02-2007, 06:09 PM
#1
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? air in the clutch lines ?
I took my car out today for the first time in a week or two.. it is pretty much the first time I've had it out in relatively cold weather since the summer. I had the brakes/slave bled prior to Pocono about 1 month ago.
Today while driving home, the clutch pedal started doing something very weird. It would stick about half way up on the return, then slowly it would move toward the floor-board on it's own. I could reach down and pull it back up and it would work fine for a while, then if I stopped for a light again, the same thing would happen... sticks about half way on the way up and slowly it appears to get sucked back toward the floor board.
The only thing that I can think of is that somehow air got into the line and when the bubbles are in the master cylinder somehow the pedal assist spring is pulling the clutch pedal to the floor without any hydraulic pressure in the master to counteract it.
I have a '95, could this be the kinematic lever or am I correct in the conclusion that I likely have some air bubbles in the line? And, if so, how did air all of a sudden get in there? Any chance the change in weather had anything to do with it?
Today while driving home, the clutch pedal started doing something very weird. It would stick about half way up on the return, then slowly it would move toward the floor-board on it's own. I could reach down and pull it back up and it would work fine for a while, then if I stopped for a light again, the same thing would happen... sticks about half way on the way up and slowly it appears to get sucked back toward the floor board.
The only thing that I can think of is that somehow air got into the line and when the bubbles are in the master cylinder somehow the pedal assist spring is pulling the clutch pedal to the floor without any hydraulic pressure in the master to counteract it.
I have a '95, could this be the kinematic lever or am I correct in the conclusion that I likely have some air bubbles in the line? And, if so, how did air all of a sudden get in there? Any chance the change in weather had anything to do with it?
11-02-2007, 06:21 PM
#2
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It sounds like air bubbles or a failing master. The lever will help on the last bit of travel but if the pedal is 1/2 down I don't think it makes much of a difference.
I would bleed the slave and see what happens.
If you have small bubbles, over time they can merge into a larger one, one large enough to cause problems. Your car was sitting for a while, perhaps that is what happened.
Anyways the solution is cheap so its worth a try.
Cheers,
Mike
I would bleed the slave and see what happens.
If you have small bubbles, over time they can merge into a larger one, one large enough to cause problems. Your car was sitting for a while, perhaps that is what happened.
Anyways the solution is cheap so its worth a try.
Cheers,
Mike
11-02-2007, 06:29 PM
#4
Drifting
I took my car out today for the first time in a week or two.. it is pretty much the first time I've had it out in relatively cold weather since the summer. I had the brakes/slave bled prior to Pocono about 1 month ago.
Today while driving home, the clutch pedal started doing something very weird. It would stick about half way up on the return, then slowly it would move toward the floor-board on it's own. I could reach down and pull it back up and it would work fine for a while, then if I stopped for a light again, the same thing would happen... sticks about half way on the way up and slowly it appears to get sucked back toward the floor board.
The only thing that I can think of is that somehow air got into the line and when the bubbles are in the master cylinder somehow the pedal assist spring is pulling the clutch pedal to the floor without any hydraulic pressure in the master to counteract it.
I have a '95, could this be the kinematic lever or am I correct in the conclusion that I likely have some air bubbles in the line? And, if so, how did air all of a sudden get in there? Any chance the change in weather had anything to do with it?
Today while driving home, the clutch pedal started doing something very weird. It would stick about half way up on the return, then slowly it would move toward the floor-board on it's own. I could reach down and pull it back up and it would work fine for a while, then if I stopped for a light again, the same thing would happen... sticks about half way on the way up and slowly it appears to get sucked back toward the floor board.
The only thing that I can think of is that somehow air got into the line and when the bubbles are in the master cylinder somehow the pedal assist spring is pulling the clutch pedal to the floor without any hydraulic pressure in the master to counteract it.
I have a '95, could this be the kinematic lever or am I correct in the conclusion that I likely have some air bubbles in the line? And, if so, how did air all of a sudden get in there? Any chance the change in weather had anything to do with it?
11-02-2007, 06:33 PM
#5
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I have not had to replace a master on any of the car that I have serviced but I have replaced a few slave cylinders. When failing, they seem to behave weirdly and often click when being used. Typical mileage appears to be over 50,000 miles but that is just from about 5 data samples.
Cheers,
Mike
Cheers,
Mike
11-02-2007, 06:33 PM
#6
Banned
If you have a '95 - regardless of miles - I'm guessing slave... After the rebuild I did on my '95, I had the exact issue. Rather then "futzing" with a 12 year old slave - I replaced it (you need 3 elbows - but it is "doable" 
), bled it out - and has been excellent since...
JD
), bled it out - and has been excellent since... JD
11-02-2007, 07:53 PM
#7
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Mine did the same thing... while driving, it was stick part way up and I had to pop it with my toe. It wouldn't go to the floor except after sitting for a while. I'd have to pull it up in the morning after driving vigorously the night before... I took her to the shop. It was the slave... all is well now.