I just put a Rodney Dickman clutch MC in my '88 GT and I had a question. It took at least 50 pumps on the bench to get it bled. Even then, on some pumps it'd still shoot air out the ports on the bottom of the reservoir. Is this normal? I was under the impression that a dozen pumps or less would do it. My friend says that it should bleed on the first one or two. My second question is, if this isn't normal, did I get a bad MC from Rodney? I thought he had awesome parts.....but he also included the wrong size bushing for the banjo/pedal. I had to re-use the tore up plastic one from the last MC.

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You would probably have better and more accurate results for thos issue if you contact him directly insted of posting here. I've heard he has good customer service so I'm sure he would be more than happy to troubleshoot with you.

Thats because your not susposed to bench bleed the clutch master cylinder, over extending the plunger in the bore can damage the valve seal. A damaged valve seal will cause fluid to push past the valve port back into the fluid resevoir, and you also loose hydraulic pressure to the outlet port.

There's a reason GM recommends removing the push rod before uninstalling / installing the clutch master cylinder - so you don't inadvertantly actuate the master cylinder without it hooked up to the system.

Just install it and let it gravity bleed and hope it's still servicable.

quote Originally posted by jelly2m8: ...Just install it and let it gravity bleed and hope it's still servicable.

That's what I did with mine. Also came from Rodney.

I installed it dry into a new (completely dry) system.
I filled up the reservoir, then used a vacuum pump at the slave to get the flow started.
Then I just let gravity take over, keeping an eye of the fluid level.
When the fluid came out clear (no bubbles) I locked it down. Has been trouble free ever since.

quote Originally posted by Tinton: I just put a Rodney Dickman clutch MC in my '88 GT and I had a question...

There was really no need to bash Rodney Here in O/T. Quite unnecessary.

He called me late last night and it is my fault. I was thinking if the bleeder is not firmly in the port it can draw in air. I was thinking slave cylinders since I had this same problem with bleeding my slave cylinder years ago. On a mater cylinder you are only pushing fluid thru the bleeder. The master I sent him may be faulty. If it is it is the first one and I have sold many. The banjo bushing thing I still wonder about. I will send him a full refund on Monday morning (I'm a morning person. That is when I think the best. Call me late at night and I may not be too coherent).

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Rodney Dickman

Fiero Parts And Acc's Web Page:
All new web page!:www.rodneydickman.com
Rodney Dickman's Fiero accessories
7604 Treeview Drive
Caledonia, WI 53108
Phone/Fax (262) 835-9575

quote Originally posted by Rodney: I guess even in the morning I am not coherent. It is possible that air can be drawn back into the master cylinder chamber while you pump the piston when bench bleeding. If an obstruction gets in the plastic bleeder screw hole I now supply with my masters now it could block the hole and cause some air to enter past the piston seal and/or the bleeder screw. I have these made for me. Anything is possible.

Sorry to bash you in that other thread, I do kinda wish that at least ONE part I buy works right out of the box though .

I must've pumped the MC 50-60 times trying to get the last bit of air out. It seemed like it'd get the air out, then when releasing the piston 2 bubbles would come up from the ports on the bottom of the reservoir. Instructions said to keep going til no bubbles (same advice that my friend gave me and he does this sort of thing all the time), so uhhh....I kept going. Did I damage the seal? Was it fine to begin with, and bench bleeding damaged it? I wanted to bench bleed it real well, I just had problems with my old MC where I let it run dry while flushing the system and it seemed like I never got the air out of the bore again. I wanted to make sure the new one was 100% bled before getting it in the car. Do you think it'll still work, or maybe I can exchange it? I bled and bled yesterday, til no more bubbles came out of the slave. Started the car and it wouldn't even come close to going in gear, and the MC felt kinda weird. Almost no resistance high up in pedal travel, but a lot more close to the floor.

How can pushing the piston in damage the seal? IIRC, just using it normally extends it all the way through its travel. I've never driven a manual Fiero that didn't require pushing the clutch all the way to the floor to get disengagement. What if I bench bled it on the car, using the pedal? Would that keep the piston from overextending?

[This message has been edited by Tinton (edited 01-14-2012).]

quote Originally posted by Raydar: That's what I did with mine. Also came from Rodney. I installed it dry into a new (completely dry) system. I filled up the reservoir, then used a vacuum pump at the slave to get the flow started. Then I just let gravity take over, keeping an eye of the fluid level. When the fluid came out clear (no bubbles) I locked it down. Has been trouble free ever since.

I did exactly this when I replaced the one on my Indy. Took maybe 15/20 minutes and no problems at all. What would be the reason for wanting to bench bleeding a clutch master?

kevin

Alright, now I realize what was happening. When you push the piston all the way into the MC, it pushes it past the ports on the bottom of the reservoir. That's where the air was coming from. The MC was bled when bubbles stopped coming out of the tube that was hooked up to the port. That happened after like 5 pumps .

I always bench bleed clutch master cylinders.