Tips on Adjusting the Clutch Slave Pushrod?

[JohnnyMead]

I'm adjusting the slave cylinder pushrod as per Bentley and it says to leave .030 slack. Is that with the return spring in place or the spring removed? Seems like that spring takes up all the play, but the way its written it sure sounds like its measured with the spring in place.
Between this and bleeding the clutch, I'm getting kind of lost trying to get the clutch right. Anybody have a good step by step for this adjustment?
Many Thanks,
John

 

[TR3driver]

The way I do it is to pull the lever back against the spring pressure while checking the clearance; but that's only so I don't have to fight that spring on and off just to check the adjustment. There is no other reason the spring needs to be installed first.

The .030" number is for the early Lockheed slave (note the comment about "twin-bore" master cylinder); if you check the early handbook at the front of the Bentley (page 41) it says .075" instead. That number was increased to .100" in later handbooks. Some sources even give .125" as I recall; others .063" (1/16").

The actual clearance isn't critical, the main thing is to ensure that it never goes to zero (it will get narrower as the clutch wears, zero means the clutch is not fully released). So I generally just pull the lever away from the slave (against the spring pressure) and check that I can rattle the pushrod around a bit. Once you get accustomed to the car, you can alter the meaning of "a bit" to suit your tastes. The more clearance you have, the farther you have to depress the pedal to release the clutch. When the pedal becomes noticeably higher, it's time to adjust the slave.

PS, be sure the slave piston is bottomed in the bore while you are checking the clearance. It should have already been pushed there by the spring, but sometimes the spring is weak or has been replaced with the wrong spring by a DPO. If the spring isn't strong enough to push the piston to the bottom immediately, the spring should be replaced. Otherwise, the pedal height becomes erratic while driving, which is really annoying.

 

[TR4nut]

If I remember correctly, what I did to set this on my TR4 was the following:

1) Detach return spring
2) Adjust pushrod & fork to take up all clearance - use middle hole on throwout shaft
3) Back off on locknut until you get correct clearance between nut and fork.
4) Keeping locknut in same location on pushrod, tighten pushrod onto fork
5) Attach return spring

Pretty sure that's how I did it, and so far, so good!

Randy

 

[BobbyD]

Moss Motors has added MossTV to their site and to YouTube with great How To videos. This section has one on clutch bleeding.

 

[JohnnyMead]

Thanks for the replies everyone! Yeah, I had .030 stuck in my head - I think that's the master cylinder end play.

I was thrown off by how far out of adjustment I found the pushrod. Seemed like there was .5" or more when pushing against the spring.

When I bought the car the spring was missing - very strange clutch behavior!