-Q-

iTrader: (10)

I am swapping a LS1 and T56 into a '75 Corvette, and I'm finally getting around to bleeding the clutch. The clutch and trans are stock T56...the clutch master is a custom unit bought from Custom Image Corvettes, and is basically an 80s style truck master with a braided line and fitting that will plug into the T56. I had to use a custom unit because the stock slave won't bolt to the Corvette firewall at the correct angle. I am using the stock T56 rubber line and resevoir.

I have been trying for the last couple hours to get this thing to even START bleeding, and no dice. I'm using a Tick Speed Bleeder, but just to be sure I'm closing the bleeder all the way when I release the clutch pedal. The fluid level in the clutch reservoir hasn't moved a single millimeter. If I submerge the end of the bleeder while pushing the clutch in, I was getting some air out for a while and then even some dirty fluid squirting out, but no matter what I try, I can't get the system to draw fluid from the reservoir.

Am I missing something? This clutch master is brand new. Everything else was functioning perfectly when the T56 was pulled. I have triple checked all the connections.

Help?

HoLLo

iTrader: (17)

I had no issues bleeding mine on my 01 WS6 using the Tick Speed Bleeder, but for some reason when we did an almost identical clutch setup to a buddy of mine's 06 GTO, we HAD to use a MityVac to begin, and then finished up using the Tick Speed Bleeder. See if you can get a hold of a MityVac to start it off.

-Q-

iTrader: (10)

Well I went to Advance to see if they would have a Mityvac and they didn't. So I came back and fooled around with it a bit more.

No matter what I do, the level in the reservoir will not fall. I finally pulled the hose from the reservoir to the master off, and it drained fine...so no obstruction there. I'm starting to get suspicious of the master itself at this point. So I had my wife push the clutch in, and I covered the nozzle that the hose to the reservoir attaches to with my finger. Then I had her let the clutch out. I was expecting there to be vacuum against my finger where the master would normally draw from the reservoir. But there's nothing.

I tried this several time, and never felt any vacuum against my finger. Should there have been? I'm assuming that's how the master draws fluid from the reservoir, but I'm not sure, honestly...

Sound like a messed up master?

Brian Coles

Not sure but check the shaft from peddle to master. If its the two piece one it can break and telescope into its self. You push peddle but shaft collapse so plunger in master barley moves. Happened on a clutch install.

studderin

iTrader: (28)

if its not to hard take the master out and bench bleed it, sounds like its dry has get s air poket around the piston and it dosnt move fluid. Just compresses the air over and over. Tech, you dont have to remove the master, just losen the bolts so you can tip in in place, and probally take the rod off the petal and push that with you hand to bleeed loosely bolted or unbolted but still around the firewall.

If its a big bitch to get the master out, try tapping on it, so break up a air pocket. Sotimes that helps. And jack the rear of the car up, get the master to tip so gravity help with the air pocket. Thats helped too, I remember some long night at newera Me and whoever would be bleeding the clutch for ever it it wouldnt get any pedal. Some weird build the master could be bench bleed, waiting for the line, or trans. But jacking the car way up tilled the mater to get it to start bleeding, Its a swap so sometimes the master is tipped alot on the firewall, and they dont bleed themselves at that angle.

gconnoyer

iTrader: (1)

Take the line off where it connects to the tranny and bleed it like you would the slave.
Have someone hold the line, and slowly press the pedal down, then have them put their finger over it before lifting off of the pedal (just like opening and loosening the bleeder screw) repeat util you get a a steady stream.

No need to take the master off or anything complicated

jmd

iTrader: (4)

The master cylinder alows for fluid to flow through it when it is fully released.

If the master cylinder pushrod is pressed into it when it is installed to the firewall, it's blocking flow.

Adjust the pushrod until the pushrod hole lines up with the stud on the clutch pedal.
Then use your bleeding method.

Ferocity02

iTrader: (60)

Try putting a vaccum on the bleeder line to draw fluid into the system, it wont bleed if there is only air in the system. Basically you need to prime the system with fluid before any magic will happen. I had to do this on my Silverado t56 swap. Slave, master, and lines were all dry. I put a tube on the bleed line and used my lungs to create enough of a vaccum to get the clutch fluid going.

-Q-

iTrader: (10)

Alright thanks for the suggestions, guys. I will try it again. I'm out of town now, but will be back in a few days.

Removing the master again is a task I'd rather not even try, so I'll give some of the other methods a shot first.

-Q-

iTrader: (10)

Well here I am, a couple months later, still fooling with this damned clutch. I finally got it to bleed using a Motive Pressure Bleeder, and got a pretty good pedal in the process...problem is, I came back out to the car a couple days later and the pedal had gone fairly soft. It won't engage the clutch until the very bottom of the pedal. I bled it again using the Motive bleeder, and again got a decent pedal, but lost pressure once again over the coming days.

Today I said screw it and drove across Louisville to get a Mityvac. Figured maybe there was air holding in the lines somewhere. Mityvac did not pull the first bubble of air out of the system. Not one.

So here's where I'm at:

-I can use the Motive and get a decent pedal. Acceptable, but still has a couple inches of softness at the top of the pedal. I could live with it, though.
-Mityvac is no more effective.
-The most peculiar issue is that even once I get a decent pedal, if I try to bleed the conventional way through the remote bleeder, the fluid level in the reservoir does not fall. Open bleeder, pump clutch, close bleeder, release clutch....no change in fluid level. This is what concerns me the most.

Is this a bleeding issue, or am I looking at a damaged master? Slave? I've had no leaks or anything to speak of.

I'm stumped here guys.

jmd

iTrader: (4)

Re: "am I looking at a damaged master?"

Close the master side of the system by disconnecting the line from the slave. If it's a quick-disco like stock, it's a closed demi-system and you can check pedal feel. Does the master exhibit the soft pedal symptom at that point? If no, but it did immediately before you disconnected, then your issue is in the slave / bleeder section of the hydro. system.

-Q-

iTrader: (10)

I will have to double-check to see now that the pedal is pumped back up again...

If the master is OK, should the pedal be hard with the line disconnected?

SPEC-01

iTrader: (2)

If the line to the Slave is disconnected the pedal should be firm. Do not try to push the pedal down when the line disconnected because you can damage the Master.

-Q-

iTrader: (10)

OK, disconnected the line from the master to the slave, and checked pedal pressure. Rock hard, so that was good. Plugged it back in and broke out the Motive pressure bleeder once again. Got my wife to give me a hand working the clutch pedal, and knock on wood, the pedal feels fantastic. Bled it a little out the bleeder, and then continued to work the clutch with the bleeder closed but with 15lbs or so of pressure on through the Motive. We continuously got a small bubble here and there coming up through the reservoir into the Motive tube. So we just kept on going until no more bubbles.

The real test will be to see if it maintains the pedal feel it has now, or if it bleeds down. Will let you guys know in a couple days...

1998droptopZ28

I know this is a really old thread, but I am hoping that if I bump it, someone can help me. Per my username, I have a 1998 Z28 convertible.

I had a soft clutch pedal and then the clutch pedal quit working completely (while I was 400 mi from home). I drove home with no clutch (started downhill where possible, in gear where not possible, synched with throttle to shift).

I bought a new stock master and had to loosen the brake booster to get it in. I got it in (after doing the drill mod) and I am having the same problem that Q had. I can't get the new master to take any fluid at all. I've pumped and pumped repeatedly and nothing.

I've been trying what gconnoyer suggested (bleeding through the line before connecting to the slave). It isn't working.

HoLLo suggested and Q apparently used a MityVac to start it off. How? I can't get a seal on the line where it connects and push the valve at the same time.

In theory shouldn't fluid just flow through from the reservoir through the reservoir line, through the master, and through the line and leak out when I push that valve? I get nothing. I even tried using the tube from the MityVac to blow fluid through it and still couldn't get anything.

How can I get this F&#&ing thing to start to bleed?

Darth_V8r

iTrader: (4)

When you swapped the master, was the hose from the reservoir to the master definitely flowing fluid? Possible plugged tube not allowing fluid to get to the master?

1998droptopZ28

I did not check, but it is not a used part, it is brand new.

I guess I need to check if I somehow kinked it.
Thank you.

Darth_V8r

iTrader: (4)

when the quick connect is separated, and pushing in on the check valve, I've never had fluid NOT flow out out. It always flows. I hope it's that simple for you

1998droptopZ28

I wish it were that simple. I can't get fluid to the check valve.

I know there is not a blockage in the steel braided line that runs from the MC to the Slave because I flushed fluid through it after doing the drill mod.

As I see it, that leaves two possibilities:

1. Blockage in the reservoir line
2. Blockage in the MC

I can't think of anything else that would cause it not to flow. Any thoughts?

I really don't want to have to take the entire thing back out of the car but at this point I'm running out of options.

1998droptopZ28

I figured it out, so here is a helpful tip for the next guy:
Run the reservoir tube OVER the U-bolt, not under.