Setting clutch slave cylinder push rod

[vernerberry]

Trying to adjust to the required 2 7/8" currently only able to get about 2". Book mentions holding operating lever on the clutch cross-shaft down. I guess my question is do I need someone to hold the clutch pedal down and then adjust and measure the push rod or should I measure and adjust without the clutch engaged? Hope that makes sense.
Thanks- Verner

[Forester]

Having the same issue except that I am only about 1/4" from where it should be. Looking forward to seeing answers.
Jim

[vernerberry]

Having the same issue except that I am only about 1/4" from where it should be. Looking forward to seeing answers.
Jim

Jim- To be clear, mine "seems" to engage and disengage the clutch, not 100% sure if its right, I just would like to know the correct way of measurement. Does yours work properly being a 1/4" out?

[Forester]

Yes my clutch functions as it should. The engagement point changed with the latest clutch slave cylinder replacement. When I reinstalled my transmission after the repair the clutch was as hard as a rock and the pedal did not move. I replaced the slave and it worked fine. To get the correct length of the rod I would need a longer threaded section of either the threaded section of the rod or the clevis. I've thought about making my own rod but at this point haven't had the need. the truck shifts like it should as it is.
Jim

[Paul D]

FWIW, I've encountered different length clutch slave push rods.

[lumpydog]

The green Bible gives two methods to adjusting the slave pushrod. The 2 7/8 approach OR you can adjust the push rod so that (when the clutch is fully depressed) there is approximately 1/8 in (3mm) of clearance between the bottom of the piston and the circlip at the bottom of the cylinder.

The latter is a better way in my opinion - with different length push rods, clutch plate thicknesses, etc. It gives you a good starting point for the (remaining) life of the clutch plate and ensures the slave cylinder's piston never bottoms out at either end.

The volume of fluid (travel range) moved in the slave cylinder is determined by the master cylinder. All the push rod does is determine where, in the slave cylinder, that fixed travel range takes place. Ideally the bottom of the slave cylinder's piston (when clutch is fully depressed) is as close as possible to the bottom of the slave cylinder without bottoming out. As the clutch plate wears, the bottom of the slave's piston will get a little higher relative to the circlip.

[vernerberry]

The green Bible gives two methods to adjusting the slave pushrod. The 2 7/8 approach OR you can adjust the push rod so that (when the clutch is fully depressed) there is approximately 1/8 in (3mm) of clearance between the bottom of the piston and the circlip at the bottom of the cylinder.

The latter is a better way in my opinion - with different length push rods, clutch plate thicknesses, etc. It gives you a good starting point for the (remaining) life of the clutch plate and ensures the slave cylinder's piston never bottoms out at either end.

The volume of fluid (travel range) moved in the slave cylinder is determined by the master cylinder. All the push rod does is determine where, in the slave cylinder, that fixed travel range takes place. Ideally the bottom of the slave cylinder's piston (when clutch is fully depressed) is as close as possible to the bottom of the slave cylinder without bottoming out. As the clutch plate wears, the bottom of the slave's piston will get a little higher relative to the circlip.

I appreciate the explanation about the second method, makes perfect sense and may prove easier to measure without needing calipers. I'll have a go of it tomorrow -Thanks again!

[lumpydog]

I appreciate the explanation about the second method, makes perfect sense and may prove easier to measure without needing calipers. I'll have a go of it tomorrow -Thanks again!

Yep - the approach basically sets the slave cylinder to be close (but not at) one end of its range - prior to any clutch wear. From there, as the clutch plate (etc) wears, the piston moves away from that end point. The clutch plate will wear to zero long before the slave cylinder bottoms out at the other end... which is really the goal of this exercise.

[vernerberry]

Yep - the approach basically sets the slave cylinder to be close (but not at) one end of its range - prior to any clutch wear. From there, as the clutch plate (etc) wears, the piston moves away from that end point. The clutch plate will wear to zero long before the slave cylinder bottoms out at the other end... which is really the goal of this exercise.

Option B really was a lot easier to measure, it was about 1/2" from the circlip I adjusted to 1/8" and the engage/disengage range seems to be spot on. Many Thanks!