How Do You Bleed The Clutch Slave? (1 Viewer)

[Wyoming]

I'm doing this as a seperate thread from my build thread. I'm hoping that more people see it and I get the answer fast.

We tried bleeding the clutch slave last night. My buddy pumped the clutch pedal a couple hundred times and I was under the truck with a wrench. We got a little trickle of fluid, but the clutch never firmed up. I had a clear plastic hose on the end of the bleeder valve and moved the hose higher than the valve to see if that would help, but it didn't.

What's the trick to this? We have to be doing something wrong.

 

[CruiserStuff]

Don't know your experience working on vehicles, so if my suggestions are too basic, forgive me.....

The bleeder valve is open on the downstroke of the clutch pedal and then tightened prior to the return stroke, right? If so, are you opening the valve far enough to allow the fluid to come out? You should get a full stream of fluid (with lots of bubbles/spurts at first, and fewer/less with subsequent pedal pushes/returns). Is this a new slave or an old unit? If it isn't new, are you sure it's a good cylinder?

 

[Wyoming]

Don't know your experience working on vehicles, so if my suggestions are too basic, forgive me.....

The bleeder valve is open on the downstroke of the clutch pedal and then tightened prior to the return stroke, right? If so, are you opening the valve far enough to allow the fluid to come out? You should get a full stream of fluid (with lots of bubbles/spurts at first, and fewer/less with subsequent pedal pushes/returns). Is this a new slave or an old unit? If it isn't new, are you sure it's a good cylinder?

It's a new slave cylinder and was totally empty. I was taught (For brakes and it has always worked) to pump the pedal three times, hold the pedal to the floor, close the valve and see if the pedal has firmed up. Should I be closing the valve on every single up stroke?

 

[CruiserStuff]

I was taught this way:

1) Open the valve and then push clutch pedal to the floor and hold it there.

2) Close the valve and release the clutch pedal.

Lather, rinse, repeat until no bubbles in fluid, being careful to not let the fluid in the cup go empty and, thus, put air back into the line.

 

[Wyoming]

I was taught this way:

1) Open the valve and then push clutch pedal to the floor and hold it there.

2) Close the valve and release the clutch pedal.

Lather, rinse, repeat until no bubbles in fluid, being careful to not let the fluid in the cup go empty and, thus, put air back into the line.

Okay, thanks.

 

[Elbert]

is it not similar to bleeding the brakes?

 

[CruiserStuff]

It is the same, as far as I know. I had never heard of the OP's "3 pump" method......

 

[arcarroll]

I was having the same issue turns out I just didn't have it screwed out far enough.

 

[REDBACK62]

The clutch slave unit should not take long at all. It is the same as bleeding brakes but no where near as much line to push fluid through. Just make sure you keep fluid level in the cylinder reservoir topped up during the procedure.

 

[Spook50]

It is the same, as far as I know. I had never heard of the OP's "3 pump" method......

That's how I've always done my brakes when I don't have my power bleeder or an air compressor to run it. Pump 3 times, hold pedal down, quick open and close on the bleeder valve, rinse, repeat until clean clear fluid comes out. The multiple pumps helps to build up more pressure to better push contaminates out, and also moves fluid around in new, dry lines and parts to help get rid of tiny bubbles that usually stick to the inner walls.

Except master cylinders. I always bench bleed those.

 

[Wyoming]

I took the slave off and used a syringe and a tube to fill it and then put it back on. Now the pedal has some feel. I'm going to glue the syringe and the hose together and force fluid from the bleeder valve to the reservoir. If that doesn't get the air out, nothing will.

 

[Pighead]

If the clutch slave was empty, the master may have emptied as well. You may need to bleed the master before you can successfully bleed the slave.

 

[Ras Tamanaco]

Hello all!!

So in the end, what technique is more appropriate to gravity bleed the slave cylinder?

- Pump a few times, clutch pedal to floor, open & close valve, release pedal
or
- Open Valve, clutch pedal to floor, close valve, release pedal.

I used the first one today and seemed to work pretty fine. I was a bit worry because nothing was coming out so i opened the valve a bit more and got fluid EVERYWHERE! Repeated this a few times until only fluid came out.

 

[RunTrout]

Cool tip I learned on mud:

Do this when you are using all new fluid.
Get a silicone hose long enough to go from the bleed plug to the reservoir. Pump pedal until bubbles disappear/ tighten plug. Done.

By closing the loop, you eliminate the need for help and closing the plug between pumps.

 

[Landpimp]

your is simpler...

I add a pop bottle, just run clear the tube in the bottle, zip tie it up(I use a wire as well so I can hang it off something, so it wont tip)

fill bottle with new fluid to above level of tube

attach other end of tubing(sized a bit tight) to the bleeder valve

open bleeder and now its a one man job, just pump away, when you see no bubbles, close bleeder

Cool tip I learned on mud:

Do this when you are using all new fluid.
Get a silicone hose long enough to go from the bleed plug to the reservoir. Pump pedal until bubbles disappear/ tighten plug. Done.

By closing the loop, you eliminate the need for help and closing the plug between pumps.

 

[gregnash]

So here is a question, it is recommended to bleed the clutch after replacing the Brake M/C since they are connected?

 

[Elbert]

So here is a question, it is recommended to bleed the clutch after replacing the Brake M/C since they are connected?

Clutch has its own master cylinder....not related to the brake system.

 

[tag3]

Then again, you're dirty, the tools are out, the clutch might like some new fluid.

 

[gregnash]

Ok that is what I was thinking, it is one of those "while i'm in there" scenarios.