clutch pedal goes up only when system pressurized
01-25-2018, 08:49 PM
#1
Instructor
Thread Starter
clutch pedal goes up only when system pressurized
hello everyone,
83 928 manual, recently the clutch pedal went all the way down to the floor, and had a bit of resistance the last inch before the pedal hits the floor.
I purchased a new clutch slave cylinder and installed it.
I purchased a Motive bleeder and hooked it up to the system, and pumped the bleeder up to 10 PSI.
then i cracked the bleeder valve open on the clutch cylinder. brake fluid seeps nicely. I let the system bleed for 30 seconds first time.
Then i closed the bleeder and as soon as i removed the motive bleeder, the clutch pedal fell to the floor again.
I reinsalled the motive bleeder and pumped it back and repeated the process for another four times.
The pedal goes up a few inches, but never comes back to normal.
Now the pedal feels resistance a few inches before it hits bottom, better than before, but i can not get it to come back to its previous normal level.
I purchased the master cylinder and will purchase the flexbile line from Greg Brown.
I was also advised to bleed the clutch cylinder after connecting the line and before installing it in the bell housing, which i did a few days before i purchased the pump, however, no oil was coming out of the clutch cylinder.
I had my neighbor pump the pedal and no oil came out of the cylinder.
So the only way to have oil come out of the cylinder is by pumping the system.
Should i remove the clutch cylinder and bleed it with the line hooked to it, then re-intall it and pressurize the system again and see what happens?
Is something leaking in the system preventing the lines to be pressurized?
thank you all.
83 928 manual, recently the clutch pedal went all the way down to the floor, and had a bit of resistance the last inch before the pedal hits the floor.
I purchased a new clutch slave cylinder and installed it.
I purchased a Motive bleeder and hooked it up to the system, and pumped the bleeder up to 10 PSI.
then i cracked the bleeder valve open on the clutch cylinder. brake fluid seeps nicely. I let the system bleed for 30 seconds first time.
Then i closed the bleeder and as soon as i removed the motive bleeder, the clutch pedal fell to the floor again.
I reinsalled the motive bleeder and pumped it back and repeated the process for another four times.
The pedal goes up a few inches, but never comes back to normal.
Now the pedal feels resistance a few inches before it hits bottom, better than before, but i can not get it to come back to its previous normal level.
I purchased the master cylinder and will purchase the flexbile line from Greg Brown.
I was also advised to bleed the clutch cylinder after connecting the line and before installing it in the bell housing, which i did a few days before i purchased the pump, however, no oil was coming out of the clutch cylinder.
I had my neighbor pump the pedal and no oil came out of the cylinder.
So the only way to have oil come out of the cylinder is by pumping the system.
Should i remove the clutch cylinder and bleed it with the line hooked to it, then re-intall it and pressurize the system again and see what happens?
Is something leaking in the system preventing the lines to be pressurized?
thank you all.
01-25-2018, 10:36 PM
#2
Team Owner
Sam based on our previous discussions you need to replace the master and the slave,
and add in a Greg Brown flex hose from the sway bar to the slave ,
and a new Blue/Black hose,
and release arm bushing.
this should restore the system to optimum performance,
so you wont have to go back and repeat your work.
and add in a Greg Brown flex hose from the sway bar to the slave ,
and a new Blue/Black hose,
and release arm bushing.
this should restore the system to optimum performance,
so you wont have to go back and repeat your work.
01-26-2018, 12:11 AM
#3
Former Vendor
If the blue hose (now black hose) drops below the level of the master cylinder, on its way from the reservoir, there will be a trapped air bubble in the section of the hose that is below the level of the master.
This makes bleeding a virtual impossibility.
If you replace the master, make sure you read up on how to modify the internal piston....this must be done. Use the spring from the old master, so the shortened piston will not allow the new spring to go into coil bind.
This makes bleeding a virtual impossibility.
If you replace the master, make sure you read up on how to modify the internal piston....this must be done. Use the spring from the old master, so the shortened piston will not allow the new spring to go into coil bind.
01-26-2018, 08:23 AM
#4
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And, last, but not least, flushing the clutch circuit with the nose of the car raised enough to make the CMC level(-er) with the ground will help when you have a stubborn system.