Clutch issue AGAIN! (Page 2/3)
stevep914 DEC 09, 06:14 PM
There is all kinds of internet advice in general about bench bleeding the master, so I am going to assume I can try that step. The master has maybe 200 miles on it and worked perfectly before the line broke. I will check blockage in the line when I disconnect it from the master, but doubt that is my issue. Thanks for all the input!
jelly2m8 DEC 09, 08:56 PM

quote
Originally posted by sleek fiero:

Jelly where did you get the idea that bench bleeding the MC would damage it ? Not bench bleeding is more likely to damage the MC as you can get an air lock causing problems to bleed . sleek



From the GM Service manual, from 20 plus years on here seeing what works and what doesn't and 30 years experience sending happy customers out with a properly working Fiero Clutch system.

We are talking the Fiero Clutch master cylinder, not the Brake master cylinder

[This message has been edited by jelly2m8 (edited 12-09-2023).]

sleek fiero DEC 09, 11:11 PM
Jelly whether you like it or not bench bleeding will do no harm to a clutch master cylinder. Its just that you have to use your finger to act as a check valve to stop air from sucking back in while pumping the piston. It works very well and prevents that air from entering the line and slave. sleek
jelly2m8 DEC 10, 06:03 AM

quote
Originally posted by sleek fiero:

Jelly whether you like it or not bench bleeding will do no harm to a clutch master cylinder. Its just that you have to use your finger to act as a check valve to stop air from sucking back in while pumping the piston. It works very well and prevents that air from entering the line and slave. sleek



it don't matter if I like it or not, I don't give 2 fuks past what I know how it works and having satisfied customers and making a honest living.
Vintage-Nut DEC 10, 10:21 AM
Here are ways to purge air from hydraulic systems...

Fact
My '88 GM Service manual has a clutch master cylinder bleeding procedure which is the two-person pedal method and DO NOT Warn about bench bleeding.

Like jelly2m8 said; I also use "that works and what doesn't and 30 40 years' experience" too......

In my world when a hydraulic system has been opened to air:
Bench bleeding a MC is the fastest, easiest and visional way that the cylinder is flowing fluid, and all air has been removed before it is installed in the vehicle.
Obviously, the line still must purge; I found vacuum is fastest, easiest and better than other methods which is my opinion.
stevep914 DEC 11, 07:31 PM
Well, I pulled out the master, bench bled it, and blew through all the lines to confirm there was no obstruction. Reinstalled the master, topped up the reservoir, and depressed the pedal. Fluid disappeared from the reservoir. Lowered the rear of the car, and gravity bled the system, with help by sucking on a hose attached to the bleeder on the slave. Got a steady flow of fluid, initially with air bubbles, and eventually clear with no bubbles. I will do the final step of depressing the slave piston to bleed out any remaining air.
I could get no flow through the master until I bench bled it, so with it working after I did that, I am a believer in bench bleeding. Thanks for all the comments; this forum is golden. Steve
Vintage-Nut DEC 11, 08:49 PM

quote
stevep914:
I am a believer in bench (MC) bleeding.....



I'm too and I'm happy you're moving forward on your clutch issue.

---------------------------------------------------------------------------------------------

BTW: As I said, I believe that bench bleeding is faster/better but clearly jelly2m8 doesn't agree on this subject, but nobody is 'wrong'!

The old phrase of "there's more than one way to skin a cat" means there are various ways to accomplish the same task.......

stevep914 DEC 15, 07:05 PM
Sorry guys, I was not aware of a double post, and really don’t understand how the second one got started. I am still working through this issue: master is working, pedal is moving fluid. I have no leakage in the line to the slave I can find. No air is coming out of the slave with the pedal depressed. Pushed the slave piston in to get the final air out. The pedal is high as it should be. But no movement of the slave piston when the pedal is depressed. .??? I have been on this for days now, and am stumped.
Vintage-Nut DEC 15, 10:07 PM
Did you disassembled and inspected the slave piston before bleeding the line?
Patrick DEC 16, 12:26 AM

quote
Originally posted by stevep914:

Sorry guys, I was not aware of a double post, and really don’t understand how the second one got started.



Steve, the funny thing is... this is the duplicated/second thread.


quote
Originally posted by stevep914:

The pedal is high as it should be. But no movement of the slave piston when the pedal is depressed. .???



What resistance are you feeling when you press the clutch pedal to the floor? If the slave isn't moving, the clutch pedal can't possibly feel the same as when the clutch was actually disengaging.