Clutch Master cyl problems!!
Thread Starter
Pro
Joined: Jun 2004
Posts: 520
Likes: 2
From: Mandeville, LA / Clemson, SC
Clutch Master cyl problems!!
I am doing the a4 to m6 swap on my 94...bought all new master/slave cyl and lines. Everything is empty. I can't get the master cyl to draw fluid. Shoun't it be...fill up the resivor and pump and fluid should be pushed out of the bottom???
Or...What is the correct way to fill the system up with fluid??
thanks,
Jeff
Or...What is the correct way to fill the system up with fluid??
thanks,
Jeff
Safety Car
Joined: Sep 2003
Posts: 3,599
Likes: 24
From: Orange County NY
St. Jude Donor '10-'11-'12-'13
You might want to try loosening the bleeder screw on the slave cylinder if you haven't already. Add fluid until it starts to leak out the bleeder (have something under it to catch the fluid), then close it up. After that, you will definitely need to bleed the system, but at least you'll have some fluid to work with.
The best method I have found to fill a completely empty system is to inject the fluid from the bottom up, through the slave bleeder screw, with an injector tool. I used the Phoenix tool.
The best method I have found to fill a completely empty system is to inject the fluid from the bottom up, through the slave bleeder screw, with an injector tool. I used the Phoenix tool.
Safety Car
Joined: Sep 2003
Posts: 3,599
Likes: 24
From: Orange County NY
St. Jude Donor '10-'11-'12-'13
In order for fluid to travel down to the slave, the plunger in the master cylinder needs to be FULLY extended (as far out as possible).
Based on your swap, I would guess that something (possibly the clutch pedal or some interference with it's travel) is preventing the plunger from extending fully open, which would definitely prevent any fluid from leaving the master cylinder resevoir and entering the actual cylinder.
You could try gently pulling your clutch pedal back toward the drivers seat, or you could disconnect the clutch pedal to see if that allows the plunger to move farther out (it is spring loaded inside the master cylinder).
Hopefully this is clear - if not, let me know.
Based on your swap, I would guess that something (possibly the clutch pedal or some interference with it's travel) is preventing the plunger from extending fully open, which would definitely prevent any fluid from leaving the master cylinder resevoir and entering the actual cylinder.
You could try gently pulling your clutch pedal back toward the drivers seat, or you could disconnect the clutch pedal to see if that allows the plunger to move farther out (it is spring loaded inside the master cylinder).
Hopefully this is clear - if not, let me know.
Thread Starter
Pro
Joined: Jun 2004
Posts: 520
Likes: 2
From: Mandeville, LA / Clemson, SC
I disconnected the master cyl from the pedal and it came 1/8 of an inch futher out so that might be it!!! I'm 300 miles away from the vette, back at school but i'm comming home in 2 weeks so i'll try again then. For normal operation should I adjust the stop further back so the rod comes out all of the way? Or will it be fine to bleed it and put the rod back in without adjusting it??
Safety Car
Joined: Sep 2003
Posts: 3,599
Likes: 24
From: Orange County NY
St. Jude Donor '10-'11-'12-'13
1/8" is all it takes to create the opening for the fluid to pass from the resevoir to the cylinder. You should definitely adjust the stop so that the rod is fully extended with the clutch pedal at rest. That opening is what allows fluid to be drawn into the system as you bleed, as well as during the course of normal operation if the system gets low for whatever reason.
Advanced
Joined: Apr 2005
Posts: 66
Likes: 0
From: Walcott ND
I had the same problem when I put in my new clutch master cylinder. After getting my new one in I noticed there was a block of aluminum on the back of my old one to act as a spacer, if this spacer isn't in place it won't push fluid through the system.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
5 Best & 5 Worst Corvette Daily Drivers
Joe Kucinski
The Headlights of Every Corvette Generation Explained
Joe Kucinski
5 Best & 5 Most Overrated Corvette Track Packages of All Time!
Joe Kucinski
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
Thread Starter
Pro
Joined: Jun 2004
Posts: 520
Likes: 2
From: Mandeville, LA / Clemson, SC
I pulled the resivor off and it did not have anything blocking the bore for the fluid. Its crazy I let the line hooked up to the master cyl and let it hang there and filled the resivoir up w/ fluid and it would drip out over a long time. But when you pump it it just moves air back an forth...I have no idea why it won't draw fluid.
Safety Car
Joined: Sep 2003
Posts: 3,599
Likes: 24
From: Orange County NY
St. Jude Donor '10-'11-'12-'13
I am stumped (not hard to do :o ) I'm not sure what else could be the problem, unless the master cylinder is defective.
The only other thing I can think of is completely removing the piston assembly - THEN it should take the fluid. Maybe something internal is preventing the piston / push rod from going all the way out.
The only other thing I can think of is completely removing the piston assembly - THEN it should take the fluid. Maybe something internal is preventing the piston / push rod from going all the way out.
Thread Starter
Pro
Joined: Jun 2004
Posts: 520
Likes: 2
From: Mandeville, LA / Clemson, SC
Well it was a defective master cyl. The piston was not comming back all of the way. It was hung up. I thought it was clear but when I pulled the resivoir again I put a safety pin in the hole closest to the firewall and it was hitting the piston!!!!! The rod was all of the way out too. Well I got one off of another vette and got the system bleed pretty good. Thanks for all of your input on the master cyl problem!!!
I have one more question. When you put the car in gear and push the clutch in and spin the tires by hand, should you hear the clutch disk rubbing at all. Mine does some...it sound like the brake pads. I don't want to ruin the brand new clutch.
I have one more question. When you put the car in gear and push the clutch in and spin the tires by hand, should you hear the clutch disk rubbing at all. Mine does some...it sound like the brake pads. I don't want to ruin the brand new clutch.