gulf_coast_228

Hey guys I am having a hard time bleeding my clutch line on my T56 with a brand new master and slave cylinder and searching Google shows me all kind of methods but I wanted to know from people who have actually done it. What's the best way to bleed a clutch so that I can get a good firm pedal?

My Haynes manual says to press the pedal to the floor, open the bleeder to let air out, close the bleeder, then pull the pedal back up and to repeat that sequence until it's firm.

This video here says to open the bleed screw, press the pedal down, then close the bleed screw and repeat that a few times until it's firm.

There's a ton of videos that say to use a MightyVac or other device to pull a vacuum from the reservoir and let the air bubbles come up.

Are any of these the best way? Is there another way I haven't come across that works?
Thanks in advance!

scooter

iTrader: (11)

I bench bled mine before I installed it

gulf_coast_228

Well that sucks, everything is already together and I really don't want to drop the transmission again if I don't have to.

pg29

I bench bled my tick T56 clutch master, and I had my dad crack open the bleeder screw under the car (on the trans), after I pressed down the pedal, and had him close it, before I let off the clutch, and did that probably 5-10 times as that was it. No more bubbles coming our of the clear plastic line going to a little catch can (same thing you'd use to bleed brakes)

Never had a clutch problem for the 6-7 years it's been together in my GTA.

Since your clutch master is already installed, I'd use the two man method I described above, but you may have to do it a few more times until you get no more bubbles out of your line attached to the bleeder screw on the trans.

Let me know if you need some diagrams, as I have the factory service manual for the 1998-2002 Camaros and Firebirds, and I can post up a picture of what you're looking for, and it's location.

gulf_coast_228

Any diagrams would be helpful for me, and thank you. I was able to get a small ratchet with 11mm socket up there and onto the bleed screw but wow is it a tight fit. How would you put a clear plastic line over that and still open and close it? Also is the Haynes manual wrong then about when to press down the pedal and when to open the bleed valve? It says to press down then open the bleed valve. The video says to open the bleed valve then press down. I have no idea if it makes a difference even.

scooter

iTrader: (11)

Either method works, so long as you do not release the pedal with the bleeder open, it doesn't matter. I like the open bleeder then depress pedal personally, the fluid isn't under pressure for that method when you open the bleeder screw.

QwkTrip

iTrader: (22)

It's really difficult to get fluid moving if the master cylinder isn't primed in some way. Before I connect hose to trans, I push on the valve in the end of the hose until fluid flows (gravity bleed). That'll get it to the point where pedal can move fluid.

Bottom line is T56 is a b**** to bleed in car. That's just the plain truth of it. Knowing a few tricks makes all the difference:

1. Put the back end of the car high in the air. Transmission is naturally tilted tail down in car. Problem is air collects at front of slave cylinder but the bleed valve is at the rear. Tilting the trans nose down lets air leave the slave.

2. Never let the reservoir go dry. Never ever. Or you'll have to start all over because you let air in the top of the system.

3. ALWAYS have pressure on pedal when the bleed valve is opened. ALWAYS be in motion until the bleed valve closes again. NEVER go full stroke and run out of movement. This is how you keep air from leaching back into the slave.

4. Don't jab the pedal. Moderate pressure with smooth movements. If you're too aggressive then it can emulsify air in the system. Big bubbles are easy to move and purge from the system. Millions of teeny tiny little bubbles are not easy to move. If that happens then just walk away for an hour and hope they all coalesce again into bigger bubbles.

Most people won't do this, but the best thing I ever did was punch a hole in the trans tunnel to get easy access to the bleed valve and hook up a clear tube with catch bottle. I can push the pedal and operate the valve by myself in perfect harmony. The valve outlet is submerged in fluid. And I can witness what the fluid looks like when it leaves. First perfect bleed I've ever had!

post #1296, https://www.thirdgen.org/forums/ltx-...ml#post6326067

gulf_coast_228

I hope this isn't a dumb question but how did you measure where to drill the hole? I feel like if I did this it would be off and have a useless hole in my floorboard.

QwkTrip

iTrader: (22)

The secret is I never counted on it being centered. I took some measurements relative to landmarks I could see on both sides of the panel. Seams, curve in the floor, stuff like that. Then I chose an oversized hole saw so that close enough is good enough.

soloc4

I'll say this first. I realize that you have everything assembled, so this advise will be too late for you, but for everyone else, here is what I did. I have a Tick 4th gen. master cylinder and their speed bleeder, which makes all the difference. The bleeder screw is now long enough to reach the reservoir on the firewall, I can crack open the bleeder screw, push the clutch and it simply returns the fluid to the top of the reservoir. The speed bleeder has a spring and ball internally, which prevents air from back purging in the line. Once you have a steady stream of fluid, close the bleeder and clamp the hose out of the way. No jacking, climbing under the car, or making a big mess all over the floor. One other thing I learned from a service tech, tap the clutch pedal several times (do not depress) and you will notice tiny bubbles coming back to the reservoir from the master cylinder. An air pocket will form just under the master cylinder cap, and the slight vibration of tap the pedal will dislodge them. This turned out to be a "one and done" operation for me.

gulf_coast_228

I just realized something. Does the reservoir cap need to be on while bleeding the system? Or should it be off so fluid can be added?

QwkTrip

iTrader: (22)

Either way. It's a vented reservoir so it won't really be sealed until the rubber boot is back in place after the job. Although it is brake fluid so best to minimize time exposed to air. I set the cap on unless I'm filling. Same with the bottle. And I throw away open bottles that weren't used up. I buy a bunch of the small bottles of brake fluid so I'm not very wasteful.

The remote bleeder is a great concept, but the connection at the slave cylinder is a bit hokey and susceptible to leaks. All I know is I spent a lot of money at RPM Transmissions for my T56 and they threw my brand new remote bleeder in the trash and said forget about it. (I was a little annoyed... I could have sold it!)

pg29

You're correct, it is a tight fit. I've included a picture of the Factory Service Manual's clutch bleeding procedure, although a few other members here, have given some good tips (like bench bleeding before installing the clutch master, as well as having the rear end higher).

QwkTrip

iTrader: (22)

Also make sure you use a hose between reservoir and master that is rated for brake fluid. I had some hose that degraded and filled the master cylinder with black goo. The fluid was pitch black when I flushed the system. Had to disassemble and scrape the master clean.

gulf_coast_228

Ok so I drilled the hole in the floorboard, attached the hose to the bleed valve and it worked great. However once I saw no bubbles coming through the hose and I closed the bleed valve I still have no pressure on the pedal. Reservoir is full, never went dry. I tried the method of pulling a vacuum on the reservoir to remove air that way and its clear no bubbles there either. I'm at a loss here. From what I see there is no air left in this system.

I did pump the pedal a few times and it seemed to build some pressure. Is that normal? And should I be able to hear the clutch engage and disengage? Because I'm not hearing anything under the car. While the engine is running it won't go into Reverse at all. I think that means the transmission doesn't detect the clutch pedal is pressed far enough. Hard to go into gear too. With the rear tires off the ground I can push it into gear of course but if I press the brake and clutch pedal at the same time the engine wants to die. I dont think the clutch plate is separating from the flywheel. I just don't know of why now.

This whole thing started with a clutch replacement. I have a new flywheel and clutch assembly. Does that even matter?

V6canvas

iTrader: (1)

Sounds like you're going in the right direction, but that clutch is definitely not disengaging. Did you measure the gap from the hydraulic throw out bearing to the pressure plate fingers before assembling?

When I put mine together (after replacing the clutch) I didn't measure and didn't have full release. I should have added a thicker shim behind the bearing, but I was in a rush.

scooter

iTrader: (11)

You might need a shim behind the slave cylinder. There are shims sometimes behind the slave from GM

soloc4

This measurement is crucial for proper operation. The procedure can be found here or on the internet. If you didn’t properly shim the throw out bearing, it could act like you have described.

gulf_coast_228

I still have the old slave cylinder so I will check to see if a shim was added. Looks like I have some research to do as well.

slow305

iTrader: (2)

I'm kind of in the same boat in regard to the hydraulic release bearing -- 1982 Camaro with a T10 that I'm trying to convert to hydraulic while doing an LS swap. I have the American Powertrain Hydramax bearing. I didn't get their fancy master cylinder, just what looks like a stock 4th gen F-Body master cylinder. The bearing comes with a pack of shims that you're supposed to measure and do some math on how many shims you need:

https://americanpowertrain.com/heil-...gnimWOVC2tE13A

Going through my notes when I did this back in May or June, my "A" is 3.33, and "B" is 2.66, so how many GM (.09) shims do I need?

A-B-.150/.09 = ?? Anybody want to take a shot?

I'll keep what I came up with a secret, because it's probably wrong because my clutch pedal has zero resistance. Already looking forward to pulling the transmission by myself, but at least I have a garage.

Pat

gulf_coast_228

Old thread but I wanted to post an update on how I solved this issue in case anyone comes across it in the future. I am lucky that I did not need to drop the transmission and add a shim behind the slave cylinder. Back in 2014 when I first did my engine and transmission swap I did not know to spray down the holes I drilled in the firewall for my clutch master cylinder with sealant (converted from automatic to t56 when I did the LS1 swap). The result was 6 years later it had developed rust and started to crack. This meant when I pushed down the clutch pedal the firewall would flex enough so that there wasn't enough pressure on the hydraulics to disengage the clutch. With some help we cleaned up the rust and installed a plate to brace the master cylinder. But it still wasn't shifting right. I would have to really force the car into gear. Sometimes I could wait for the car to warm up and then it would shift but it would still be more difficult to than it should be.

Then as I was driving I heard a snap under the dash and the clutch pedal went to the floor. No clutch pressure at all. Once I pushed the car safely out of the way I got under the dash to see what happened. My help did not put on the retaining clip on the clutch pedal to master cylinder rod post. Heaven knows how I was able to drive it before that happened but apparently it was pushing in the piston at a weird angle and it was not enough pressure to shift properly. Thankfully I don't really drive it often or it could've happened at a worse place than it did.

With a new clip in place with the rod properly positioned and the plate to brace the master cylinder everything is super smooth and feels like new again. Moral of the story is to double-check everything is in place when you have help

scooter

iTrader: (11)

Firewall cracked because of the lack of reinforcement, and why GM put a second plate in that area. Had nothing to do with corrosion. Eventually everyone who does the swap without the reinforcement will have the firewall crack

gulf_coast_228

Oh wow I didn't know that. I mean it's not like they didn't offer Firebirds in a manual transmission at all, there were preforations in the firewall where it looked like the master cylinder would go already so to me that meant it could handle the master cylinder and it must have been something I did wrong. Makes me feel a little less stupid knowing it wasn't completely my fault.

slow305

iTrader: (2)

Finally figured this one out. After attempting to bleed the bearing I don't know how many times and never getting a steady stream of fluid and the clutch pedal having almost no feel, I finally noticed buried under the brake booster a small splash of fluid under the nipple coming off the master cylinder (brand new bought last year). The little o-ring holding pressure on the nipple was somehow bad so it was probably leaking fluid and sucking in air. Even taking it out and comparing to a new o-ring, it looks OK. Anyway, replaced it, bleed air out from the reservoir using a hand pump, and what to you know, pedal is normal and it appears the bearing is engaging the clutch (verified with a $25 borescope that wirelessly displays on my phone).

Pat