Clutch mystery

[artificialist]

Originally Posted By: TallPaul
It's going in tomorrow for a new master cylinder. They will bench bleed it before installing it in the firewall.

What I don't get is that brake master cylinders typically last the life of a vehicle, so why not clutch master cylinders? Or is it just that the clutch linkage is more sensitive than a braking system?

At least they could include an adjustment to the hydraulic clutch.

And what is the great advantage in a concentric slave cylinder? I understand external slaves are still common in manual transmission applications.

In many cases the clutch master cylinder does last as long as the brake master cylinder.

As for the concentric slave cylinder, I think it reduces the number of parts that must be installed on the assembly line, but I could be wrong.

 

[TallPaul]

Installing a new master should be easier than bleeding the unit in place. They bench bled it and installed it and now can't get any more pedal than I had with the leaking one. If I were this ship, I would simply refuse to do this work anymore.

I may be putting this truck up for sale. I have about hand enough with it.

 

[TallPaul]

They installed a PowerTorque master cylinder but had a lot of trouble bleeding it. Finally got only enough pedal so you could shift in to gear. I told them to drive it around and make sure it is working. By the end of the day the pedal was gone. They returned the master and put another Power Torque in. They were able to bleed it to perfection (only an inch of free play at top and engage 1 to 1.5 inches off the floor). By the end of that day (it's Friday now) the pedal was gone. He is going to try a Motorcraft master cylinder next week.

 

[Kiwi_ME]

Check that the master cylinder stroke is reaching end of travel when your foot is off the pedal. The MC piston must be allowed to fully relax to open the system to the reservoir and self-adjust.

 

[TallPaul]

Just talked to the shop. They tried a different bleeding method and it worked great. They got a good pedal and since they are now diagnosing an intermittent engine problem of missing, I told them to drive it for parts runs etc. They have driven it all day and the clutch is great. They are going to keep it tomorrow to continue working on the running problem before giving it back.

 

[TallPaul]

No fuel smell on dipsick. So maybe not bad enough to change out.