Techniques for bleeding clutch slave?
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Joined: Apr 2005
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From: Santa Clara CA
Techniques for bleeding clutch slave?
I haven't successfully bled mine yet, and I'm wondering if any of you have a more detailed, workable description of how to do this painlessly, saving a first-timer the agony of trying to do it according to the terse shop manual!
Racer
Joined: Aug 2003
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From: Loganville Ga
The way I did it was to take the slave off and get the bleeder valve to the highest point. I held a piece of flat metal in my hand with an indentation in it for the shaft of the slave to seat in. Then by hand, I pushed the piston into the slave, tapped it a few times, then repeated - the whole time with the valve pointing straight up. It took about 10 times but it was the only way I found that got all the air out of it.
Safety Car
Joined: Sep 2003
Posts: 3,599
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From: Orange County NY
St. Jude Donor '10-'11-'12-'13
After trying several methods (and not getting the best results), I finally purchased and used the Phoenix Injector Tool.
It was simple to use and bled the system of all air in less than 5 minutes. I'd highly recommend the investment.
It was simple to use and bled the system of all air in less than 5 minutes. I'd highly recommend the investment.
Melting Slicks
Joined: Apr 2003
Posts: 2,150
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From: NS
Originally Posted by czissman
I haven't successfully bled mine yet, and I'm wondering if any of you have a more detailed, workable description of how to do this painlessly, saving a first-timer the agony of trying to do it according to the terse shop manual!
Racer
Joined: Aug 2004
Posts: 377
Likes: 1
From: Redmond Wa
I took mine off to bleed it but I also pushed the slave piston all the way to the back of the cylinder (watch the fluid level in the master cylinder as it will overflow).
After I pushed the cylinder all the way back, I blocked it in that position with a short piece of 2x2 that I had previously drilled two ¼ inch holes completely through at 2-3/4 inches on center. I had also drilled a third hole exactly between the first two holes only about a ¼ inch deep as a place to hold the piston rod. I used two ¼ inch by 2 -1/2 inch screws and nuts to hold the block of wood to the slave (don’t torque the nuts, just us enough pressure to bottom the piston in the back of the cylinder). This effectively held the piston in the back of the cylinder. This method keeps the slave cylinder volume at a minimum which creates less possibility of trapped air remaining in the cylinder after your done bleeding.
At this point I pointed the slave upward with the bleed screw at the top, attached a clear piece of tubing to the bleed screw so I could watch for air bubbles and put the other end of the tube in an empty Corona bottle. From there you bleed it like a set of brakes. While the peddle is traveling down open the screw. When the peddle hits bottom, close the screw, peddle up, repeat. Watch the level of fluid in the master cylinder as it’s only good for about three or four cycles then your sucking air.
When you’re satisfied that the air is out of the system, remove the block of wood from the slave slowly. You need to loosen the nuts a little and then add fluid to the master, loosen the nuts some more and then add more fluid. If you aren’t careful about this you will suck air into your perfectly bled system.
Next time I do this I will make my little 2x2 jig out of metal as the slave piston eventually split it like a wood splitter. Fortunately, I was done bleeding when this happened.
Hope this helps.
Chris
After I pushed the cylinder all the way back, I blocked it in that position with a short piece of 2x2 that I had previously drilled two ¼ inch holes completely through at 2-3/4 inches on center. I had also drilled a third hole exactly between the first two holes only about a ¼ inch deep as a place to hold the piston rod. I used two ¼ inch by 2 -1/2 inch screws and nuts to hold the block of wood to the slave (don’t torque the nuts, just us enough pressure to bottom the piston in the back of the cylinder). This effectively held the piston in the back of the cylinder. This method keeps the slave cylinder volume at a minimum which creates less possibility of trapped air remaining in the cylinder after your done bleeding.
At this point I pointed the slave upward with the bleed screw at the top, attached a clear piece of tubing to the bleed screw so I could watch for air bubbles and put the other end of the tube in an empty Corona bottle. From there you bleed it like a set of brakes. While the peddle is traveling down open the screw. When the peddle hits bottom, close the screw, peddle up, repeat. Watch the level of fluid in the master cylinder as it’s only good for about three or four cycles then your sucking air.
When you’re satisfied that the air is out of the system, remove the block of wood from the slave slowly. You need to loosen the nuts a little and then add fluid to the master, loosen the nuts some more and then add more fluid. If you aren’t careful about this you will suck air into your perfectly bled system.
Next time I do this I will make my little 2x2 jig out of metal as the slave piston eventually split it like a wood splitter. Fortunately, I was done bleeding when this happened.
Hope this helps.
Chris
Last edited by Grace91; Apr 25, 2005 at 01:55 PM.
Race Director
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From: Stafford, Virginia Kittah, Kittah, Kittah...
One thing I've always wondered about but haven't tried yet... The bleeder screw from pictures I've seen looks just like the one on your brake caliper... I'm wondering if you could replace the normal screw with a speedbleeder??? Seems that would make for an occasional quick flush for the guys who like to do it frequently...
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From: Santa Clara CA
I opted for the simple method first (the "GM way"), which worked fine for me after all. But I think I will invest in the too you described, as I'm sure I still have some air in the lines.
Thanks to all who helped with this!
Chuck
Thanks to all who helped with this!
Chuck
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From: Centerville OH
Originally Posted by Grace91
I took mine off to bleed it but I also pushed the slave piston all the way to the back of the cylinder (watch the fluid level in the master cylinder as it will overflow).
After I pushed the cylinder all the way back, I blocked it in that position with a short piece of 2x2 that I had previously drilled two ¼ inch holes completely through at 2-3/4 inches on center. I had also drilled a third hole exactly between the first two holes only about a ¼ inch deep as a place to hold the piston rod. I used two ¼ inch by 2 -1/2 inch screws and nuts to hold the block of wood to the slave (don’t torque the nuts, just us enough pressure to bottom the piston in the back of the cylinder). This effectively held the piston in the back of the cylinder. This method keeps the slave cylinder volume at a minimum which creates less possibility of trapped air remaining in the cylinder after your done bleeding.
At this point I pointed the slave upward with the bleed screw at the top, attached a clear piece of tubing to the bleed screw so I could watch for air bubbles and put the other end of the tube in an empty Corona bottle. From there you bleed it like a set of brakes. While the peddle is traveling down open the screw. When the peddle hits bottom, close the screw, peddle up, repeat. Watch the level of fluid in the master cylinder as it’s only good for about three or four cycles then your sucking air.
When you’re satisfied that the air is out of the system, remove the block of wood from the slave slowly. You need to loosen the nuts a little and then add fluid to the master, loosen the nuts some more and then add more fluid. If you aren’t careful about this you will suck air into your perfectly bled system.
Next time I do this I will make my little 2x2 jig out of metal as the slave piston eventually split it like a wood splitter. Fortunately, I was done bleeding when this happened.
Hope this helps.
Chris
After I pushed the cylinder all the way back, I blocked it in that position with a short piece of 2x2 that I had previously drilled two ¼ inch holes completely through at 2-3/4 inches on center. I had also drilled a third hole exactly between the first two holes only about a ¼ inch deep as a place to hold the piston rod. I used two ¼ inch by 2 -1/2 inch screws and nuts to hold the block of wood to the slave (don’t torque the nuts, just us enough pressure to bottom the piston in the back of the cylinder). This effectively held the piston in the back of the cylinder. This method keeps the slave cylinder volume at a minimum which creates less possibility of trapped air remaining in the cylinder after your done bleeding.
At this point I pointed the slave upward with the bleed screw at the top, attached a clear piece of tubing to the bleed screw so I could watch for air bubbles and put the other end of the tube in an empty Corona bottle. From there you bleed it like a set of brakes. While the peddle is traveling down open the screw. When the peddle hits bottom, close the screw, peddle up, repeat. Watch the level of fluid in the master cylinder as it’s only good for about three or four cycles then your sucking air.
When you’re satisfied that the air is out of the system, remove the block of wood from the slave slowly. You need to loosen the nuts a little and then add fluid to the master, loosen the nuts some more and then add more fluid. If you aren’t careful about this you will suck air into your perfectly bled system.
Next time I do this I will make my little 2x2 jig out of metal as the slave piston eventually split it like a wood splitter. Fortunately, I was done bleeding when this happened.
Hope this helps.
Chris
I did exactly the same thing, except I made my plate out of a scrap piece of sheet stock I had laying around. I had always used the service manual method previously and went through 3 slaves before I built the bleeder plate. I haven't had a bit of trouble with the slave since.
