How to bleed a clutch with a Mity Vac

**Hi-Po** · 01-26-2011, 05:33 PM

Originally Posted by JwMAURER

Maybe I'm assuming too much here. Is the mity vac different from any other bleeder that you can buy? I have one that looks just like it so I was using that and it was making no difference. So I switched my factory master back out with a tick performance adjustable master cylinder that was in before but I thought that's what was allowing air into the system. I sent it back and they tested it and said all is well and nothing was wrong which is why I just bit the bullet and dropped the tranny and replaced the slave. After installing the master last night I seem to have the same problem. Just not as bad. I noticed some air bubbles in the "on master" reservoir but they wouldn't float out the tube or get pushed back into the system to be bled out. I once again tried the vacuum technique assuming it works The same as The mity vac and the air bubble moved to the tube neck but no further? I'm stumped. I tried to gravity bleed it but I only get drips out the bellhousing and no steady stream. Both the master and slave are brand new now and I hose clamped both the master and reservoir ends of the fluid line yet I'm continuing with The same problem! I'm about to rip my hair out

It sounds like you have a seperate problem. The MityVac should have no problem bleeding the clutch. I don't fully understand what your going through without being there, but the bolded text struck me as odd. Why to you have these lines hose clamped?

I just cant see any reason it would not work, it has worked for myself, and many others perfectly.

**Hi-Po** · 01-26-2011, 05:35 PM

Looks like my video is down in the original post. Here it is again.

http://s61.photobucket.com/albums/h4...t=MVI_1843.mp4

**JwMAURER** · 01-26-2011, 05:40 PM

I hose clamped the rubber line that descends down from the upper reservoir that u fill and runs down to the master and I clamped it there as well. I clamped them because I'm trying to guarentee it's sealed. When I was bench bleeding the master before I put it in the car you can look into the top of the master (assuming you've never dealt with one) and you can see a couple bubbles. When I applied vacuum they only moved as far as the tube inlet running up to the reservoir hole where the vacuum was being applied. My problem Is I'll adjust my pedal perfect. But over night I'll lose about 2 inches off the pedal which makes a dramatic difference seeing is how with this bigger bore master cylinder I only had about 5 inches of pedal to start with. With factory master it would bounce between missing 1/2 pedal to a 1/4 pedal. But I'll regain full pressure from time to time. I notice the biggest drop in pedal over night. But I'm not losing any fluid.

**JwMAURER** · 01-27-2011, 04:31 AM

How about this possible problem? Is it normal for the salve input arm to have some play/wobble in it? I noticed the old one before I changed it had alot of wiggle in it and the new one was rock solid. Well when I replaced the master the other night I noticed the new slaves arm is beginning to wiggle just the same. Just not as bad. Is that normal to have play in that hydraulic arm or is that a bad thing?

**Cutlass** · 01-27-2011, 03:47 PM

What's a slave arm??

**JwMAURER** · 01-27-2011, 04:11 PM

I'm trying to describe where you attach The hydraulic fitting off the master to the slave at the inlit on the side of the bellhousing. There is a picture above at the top of the thread

**Cutlass** · 01-27-2011, 05:26 PM

ok. Well if that fitting isn't leaking fluid, I think your ok.

**JwMAURER** · 01-27-2011, 05:40 PM

Ok sweet. I really didn't want to drop the tranny again haha.

**toplessLS1** · 01-30-2011, 02:30 PM

Need some further explanation on the bleeding process.

Replaced the master clutch cylinder, but the pedal isn't firm enough using the mityvac. The bleeder valve is too hard to reach so I didn't bleed it there, just with the mityvac from the reservoir.

Question: Is it possible to bleed the entire system (master and slave) using the Mityvac without being under the car and using the bleed valve? I mean in all of the back in forth I can't tell.

**Cutlass** · 01-30-2011, 05:20 PM

Yes the mity vac should be able to suck all the air out of the system. You may need to pump the pedal up several times after you bleed the system. manually pull the pedal back up if you have to.

**toplessLS1** · 02-05-2011, 12:03 PM

Today I crawled under the car and was able to bleed the slave. Weird thing is the pedal felt good at first, but after a lap around the block it started to get soft and even stick a little.

While under the car I noticed the hard line part of the slave that attaches to the fluid line wiggles a little. I took off the fluid line and the hard line still wiggles, almost like it is loose or something. The bleed part of the slave was solid and does not wiggle like the fluid line part of the slave. Could this be my problem?

**JwMAURER** · 02-05-2011, 12:57 PM

I've wondered the same thing also. Mine was really loose to the point where I dropped the transmission and replaced it. It was rock hard when first installed and not even a week later it already has some movement in it so I think it's normal. I took my car to a transmission shop to help figure out what's going on because every other attempt to bleed it has gone unsuccessful. They gave me some good insight but I haven't been able to try it yet. Dependent on if u have a factory master or a tick performance master the problem was pointed out to me. The piston end of the master needs to be turned below the out take of the hydraulic line so the air trapped at the piston can be bled of of the system. With the master installed in the car you will have to lift the front of the car as high as u can and see if you attained the proper height to shift the master so the air will float up (actually to the bottom fluid line end) and out the system. Other wise by physics the air will never Tavel away from the piston therefore after immediately bleeding it you will have great pedal pressure until a few hours later when the air settles back against the piston. Mind u this is only required if all these other techniques don't work. If your using the factory master you can unhook it from the pedal then unhook The 2 13 mm bolts holding it in place and just rotate the head down to put the butt end higher up. With my tick master I don't have the room to just unbolt it. Hopefully this helps. Let me know how it turns out

**toplessLS1** · 02-05-2011, 01:25 PM

Thanks Jw. It all started when my said she jumped on the gas to get into traafic. She said the pedal stuck to the floor when going hard from 1st to 2nd. Since that time the pedal has been softer than normal and a little sticky.
I replaced the master thinking the seals were gone with a factory unit. The old black fluid was replaced at the same time. The mityvac and normal bleed procedure hasnt improved the pedal.
Still thinking the slave is bad. As if the seals are gone in the slave and it cannot hold enough pressure to maintain a hard pedal.

**JwMAURER** · 02-05-2011, 01:36 PM

Well the factory master has been known not to supply enough fluid pressure to fully disengage the clutch causing your rough shifts. But what your wife experienced is when she ripped on it she boiled your hydraulic fluid. I love gm but there wasn't alot of thought put into the routing of the clutch line. It runs down the side of the header and the cat. So any spike in rpm and the pipes will boil your fluid. Fresh fluid is clear. Dot 3's boil point can tolerate about 5 boil overs then it turns black and that's when you lose your pedal until you pull it up with your foot. That's why I bought the tick performance clutch master cylinder. It's adjustable so you can guarentee your clutch is fully disengaged and they wrap the hydraulic line with a heat resistant cover. There are some other perks but if you can't justify $400 on a master then I'd say Atleast uninstall your factory master, do the drill mod and then by some header tape and wrap your hydraulic line from the master to the slave to help prevent a boil over. Dot 4 has a higher boil point but I've heard synthetic fluids causing hell with the factory master cylinder. Ive had the same problem you are talking about until I got the tick master. Since then I just haven't been able to bleed it which as soon as the weather clears up I'm going to try the method I told u about. If your slave is actually bad you will be seeing fluid leaking out of your bellhousing and obvious fluid level dropping in your reservoir. So if your not dealing with that I'd say it isn't worth dropping the tranny yet. Just make sure you shift slow. These tremec transmissions have very weak syncros. A few bad shifts and you could be needing new ones and the t56 is not cheap to work on.

**Cutlass** · 05-25-2011, 06:00 PM

I discovered another source for possible clutch hydraulic problems. The master cylinder reservoir hose on my car was routed(from the factory) under the retainer clamp and was partially pinched off. That was causing me erratic operation and occasionally a sticky clutch pedal. I rerouted it up over the clamp(not shown)

**toplessLS1** · 05-26-2011, 06:01 PM

No leaks at the slave. Still have problem. Will try drill mod.

**DarthD** · 05-18-2012, 06:00 AM

The video requires a password

Originally Posted by Hi-Po

Looks like my video is down in the original post. Here it is again.

http://s61.photobucket.com/albums/h4...t=MVI_1843.mp4

**toplessLS1** · 05-18-2012, 01:28 PM

I finally ended up dropping the tranny and replacing the slave...along with some other goodies. New slave did the trick for me.

**2002ssslp** · 05-18-2012, 03:45 PM

Thanks for the info, it really helps to have pictures. I'm happy with the results, clutch feels great.

**cruzincamaro** · 06-08-2012, 07:32 PM

My clutch fluid is black too. Can anyone tell me the easiest way to replace it? And am I correct in presuming that with the mityvac, I don't have to go under the car and I can do it alone? Can't view hi-po's video w/o a pass word. Don't know much about computers. Did I miss it somewhere? All Help welcomed. Thanks...