Any way to diagnose a slave cylinder?

[ascdesigns]

I just did a gravity flush on my '98 Ranger. The clutch was working just fine up to that point but the pedal wasn't very smooth going in and out. Never did I let the fluid drop more than 1/2 reservoir before topping it off. I also pulled the master cylinder through the firewall and tilted it so that the pushrod was lower than the hose connections on the master. Bled about a pint of fluid through the system and closed it up tight. No air bubbles in the hose off the slave nipple.

The pedal feel improved immensely - smoother and "lighter". BUT... after a day of driving it or so, when I put it in reverse, clutch in, the car started creeping as though the clutch was partially engaged. Yanked it out of reverse, pumped the clutch a couple times and all was well again.

Is this more of a symptom of air that somehow got past my bleed/flush technique or a slave cylinder that coincidentally decided to start crapping out? There are no leaks at the slave cylinder side, the reservoir stays full, and I did look inside the bellhousing via that rubber-covered "port" - dry as a bone.

Thoughts? Bleed yet again? Is there an actual way to see/check if a slave is giving up the ghost?

If I do have to replace the slave, can the tranny be pulled back just far enough to remove/replace it or does it need to be entirely dropped.

Thx,

Al

 

[rboyer]

Logic would suggest that since you bled it and it acted properly at first then what you did was correct. If over time it begins to act up then you have a problem. Most of the time the problem is the slave cylinder. And yes, when you swap out the slave cylinder you do have to pull the whole transmission. It would be alot harder to just pull back the transmission and do it while it's hanging from the truck.

 

[kimcrwbr1]

If you have to pull the tranny you may want to do a complete clutch especially if it is stock murphys law says you will be back if you dont. Also consider a new master at the same time. I allways think in terms of what I am saving in labor if I have to turn it into a shop. For the price of a shop to replace the slave cyl you can buy a complete clutch with master cyl. IMHO

 

[ascdesigns]

Good points all. I'm hoping I can get another couple months from my slave before having to replace it. I'm still recovering from the holiday expenditures!

Thx,

Al

 

[azreb]

I'm still learning about bleeding the clutch system, but it seems to me that you could disconnect the input to the slave cylinder and try the clutch pedal. If it is stiff there is a problem in the slave cylinder.

Check out this video:

http://www.youtube.com/watch?v=HgNTDGwcjZc

It seems you have to remove the master cylinder assembly completely to eliminate any possible air traps in the line. If that is the problem, the fix is much cheaper than replacing everything.

 

[ascdesigns]

Good idea. I assume two thin flathead screwdrivers will allow me to release that clip? I think I read somewhere that the master cylinder can also leak internally without showing any seepage of fluid externally. Is that a possibility?

I've already gotten some quotes locally to get the clutch, master and slave, pilot and throwout bearings replaced for around $1100, parts and labor. Give or take a $100, it seems reasonable (but of course still some money I'd rather not part with).

 

[azreb]

I released the clip on mine with a single screwdriver.

Judging from your first post, I would bet your problem is related to the bleeding process. Carefully rebleeding the whole system might save you that $1100.

 

[ascdesigns]

Yah, I'll be bleeding it again for sure. I'll probably bench bleed it this time around and then do the final gravity bleed for the slave. I forgot to mention my Ranger has about 125K miles on it and probably the original clutch/slave so it may be getting close anyways. I'm going to milk it for all it's worth though!