Bleeding clutch line

[fairmounter]

I am hoping my problem is air in my clutch line. Had my slave cylinder and rubber hose replaced recently because the pedal was not effecting the clutch as much as normal (like a leak, and it was gradual). Slave cylinder was assumed to be the problem since it was old and the master is pretty new. Now the clutch does not work at all. I was hoping that it is still air in the line. The shop is sure it needs a new clutch. I bled the line myself by the old have someone pump while you open the valve method. Fluid came out several times, I never noticed air bubbles coming out, just fluid. I am still hoping it is air since I realize it is a very difficult to spot to bleed. Should I get one of those devices that forces the fluid up through the bleeder to the mc? or does the lack of any air bubbles when I bled it make it unlikely that there is still air in there.


Strange thing, when it is running in neutral, it bogs down when I push the clutch in and I can only put it in gear with the engine off.

Please tell me it is definitely air (or the master).

 

[kalist]

Try cracking the line at the master cylinder and bleeding it there first. Sometimes air gets trapped high and doesn't work through. Make sure you have plenty of rags on hand for this.

 

[61frogeye]

Just a question kalist, if you used a pressure bleeder like an eezi-bleed do you think that might work also?

 

[kalist]

I tried a pressure bleeder on mine and was unable to get all the air out until I cracked the line. One caution about a pressure bleeder. If you are using one on a master with a plastic reservoir don't use too much pressure or you will blow fluid out where the reservoir fits on the master (don't ask me how I know this)

 

[Sarastro]

Many of the replacement slave cylinders have the bleed nipple in the wrong place. It should be in the higher hole. If not, you'll get lots of bubble-free fluid when bleeding, but there still will be air in the cylinder.

Not sure what flavor of Spridget you have, but in the Bugeye, the slave is tilted so the rearward end is ever so slightly upwards. So, it helps to put the front of the car up on jack stands or ramps to get all the air out. Even then, I often take out one mounting bolt and tilt the cylinder so the bleed nipple is a little more upward when bleeding it.

In my experience, the old-fashioned two-person bleeding method works best. But if you don't have the bleed nipple at the top of the cylinder, nothing will work.

You might want to do a search of the forum. This question has come up often.

 

[TraceZ]

I hate to ask the obvious, but have you visually verified movement of the slave cylinder and clutch fork while somebody presses the pedal?

If it's not moving, I agree you have a problem with your hydraulics.

If it's moving as it's supposed to, your clutch is the problem.

 

[fairmounter]

I don't see a second place for the bleeder nipple. The slave is installed in the car and I am looking at the bleeder nipple through the hole next to the passenger's left foot. I am pretty sure it is in the right spot.

Thanks for the tip about taking the hard line off of the master. After the disappointment of the nipple being in the right place, I was very excited at the possibility to get someone to pump the clutch for me to try bleeding it with the master disconnected. As I was looking at how to disconnect the hard line from the master, it actually took me a minute before I realized that disconnecting master will render the pumping the clutch method wanting. Sorry it was just pretty funny to me when that hit me.

So I am still needing to decide whether or not to try a forced bleeder. Assuming the nipple is on the correct hole and this in a 1972 1275 midget, does the absence of air bubbles when I bleed it make it very likely that there is not air in line?

What are the symptoms of a failed clutch master?

Any idea why it would stall when I push in the clutch with the car in neutral?
Thanks very much.

 

[kalist]

You don't disconnect the line from the master. Just crack it open slightly to allow trapped air to escape. You can do this while bleeding in the conventional manner. You do realize the pumping method has the person in the car holding the pedal down while you open the bleeder and not letting up on it until you close the bleeder?

 

[regularman]

Old trick is to use the brake as a pump to pump fluid back up the clutch line and get the air out at the master. Run a small hose from the passenger side front brake wheel cylinder bleeder to the clutch slave bleeder. Open both bleeders and crack the line at the clutch master and have someone slowly press the brake pedal and bleed the air out at the master then tighten it up and tighten brake bleeder and the clutch slave bleeder.
You have air in the line and it won't bleed out the normal way. This is a common thing with a large amount of air. The clutch master does not have enough volume to move all the fluid out of the line and one pump will never get to the air.

 

[fairmounter]

To crack the line, how many times would you turn the nut? I am picturing about a quarter turn. Should I do anything to the bleeder nipple while doing this or just push some fluid out the cracked connection?

Regularman, that sounds genius. So just like plastic aquarium tubing? I am thinking pump fluid in before attaching to the slave nipple. Has anyone else done this?

Sarastro, thanks for the tip on the search. I searched "bleed clutch" and spent 20 minutes reading the related ones that came up from the past 11 years, I did read some interesting threads but did not find what I needed. At least I am not starting a thread asking what kind hydraulic fluid to use or what you think of my plans to convert to a hayabusa engine , but sorry to add an unnecessary thread none the less.

 

[fairmounter]

You do realize the pumping method has the person in the car holding the pedal down while you open the bleeder and not letting up on it until you close the bleeder?

Yes, thanks. I have found it surprisingly difficult on two occasions to explain to a helper how to do the pedal pushing, however. One time I was pulling my hair out trying to bleed a caliper. I remember thinking, how much air could possibly be in here. Once he started pumping the brake instead of the clutch, it was incredibly fast.

 

[Guest]

I couldn't get my 1500 to pump bleed. The 1500's slave is bigger than the m/c. I pulled it of (slave), faced bleeder up, opened till no air came out. I then pushed the slave in expelleing fluid out the open bleeder. I then shut the bleeder off and released the slave sucking in fresh fluid. I repeated that a few times till no more air came out. I then pushed in the slave w/o opening the bleeder a few times and released slowly. This purges any air that may be trapped in the upper line or m/c. It pushes air out inbto the res.

My system is now 100% air free.

 

[nomad]

You say that when you push in the clutch the engine 'bogs down' but clutch does'nt release.
Have some one push the clutch pedal while you check to see how much movement there is in the clutch lever. If the lever moves enough then I agree with the shop. Clutch problems.

Kurt.