Cant shift - clutch not disengaging?

[TBone028]

Whats up everyone, hoping someone can give me some more ideas.

So my 72 240Z has a 5-speed, and when the car is off, I can shift into any gear easily and without any effort. When the car is on, I can barely shift into first, if at all. And when I am able to get it into gear, it takes a herculean effort to do so. Once I get moving, I can shift into other gears with relatively easy effort, getting easier as I upshift into higher gears. If I come to a stop and sit for a while (like at a light for example) it starts all over again and I can barely get into first gear. I had to turn the car off, shift into first, and then start the car. Reverse, is a resounding grind but usually will go into gear.

I'm hoping that it is a clutch pedal height issue, but I have not ruled out a bad master or slave cylinder. When I tried to adjust the pedal height last weekend, I could not turn the nut on the master cylinder push rod (under the dash). It looked like there was plenty of multi-purpose grease on there and didnt look rusted together, but it did not want to move. Am I supposed to clamp down on the rod with some pliers first, and then adjust the nut to give more travel? (Should the nut go towards the front of the car, or towards the back???). When I checked the fluid level in the master cylinder reservoir, it was low. Topped it off and need to check it again to see if I have a leak.

Things I have not done, but will be doing this weekend if I cant solve this with a pedal adjustment.

1) Bleed the clutch

2) check for leaking (again)

3) Order a new master and slave cylinder

4) Shoot myself.

What am I not thinking of? The attached diagram shows the adjusting nut for the pedal adjustment...for some reason I thought there was supposed to be a lock nut as well? Or is that only with adjusting the withdrawal lever on the slave cylinder? Open to any and all suggestions.

thanks,

T

[Gary in NJ]

Sounds like the Master, Slave or air in the line (which could be the result of a bad master or slave). Option 1 is the first place to go.

[ZCurves]

Sound like you are on target. But for shooting youself, please only use Jose Cuervo ammunition.

[IdahoKidd]

Hey, I just fixed this very same problem last night. Under the dash where the pedal connects to the clutch master is a rod that is threaded with a lock nut on it. If the nut comes loose, the rod can rotate and the travel of the pedal becomes limited. I am betting the car starts to move when the pedal is still very close to the floor.(?) Adjust the rod so that the free play is largely gone (when the car doesn't move when the clutch is let out to about a third of the pedal throw). I'd bet money on it!

Leonard

Number 1 in the pic above

Edited April 23, 2010 by IdahoKidd
clarification

[ArnieTX]

Make sure your pedal is not bent in to the right. It should go to the floor. Mine was binding on something under the dash. Bent it a little left and it's fine now.

[TBone028]

Well, after making adjustments at both the clutch pedal and the slave cylinder, it shifts like butter now. No grinds, no difficulty, no problems. Everything works as it should. Nice and smooth, and clutch engages/disengages nicely.

Unfortunately, the slave cylinder is f*&$*ed. It was moist, and I could tell it has been leaking. Surprisingly though, it didnt affect the test drive at all...which puzzles me. Oh well. I have new parts on order.

[TBone028]

Slave cylinder has been replaced! I had to re-use the old push rod as the new one was too long. Even after buying a new 17 mm flare wrench, I still had to use locking pliers to break free the clutch hose. I have a clutch hose in the mail just in case I need it in the future.

[skyrit]

TBone028

I'm replacing my master cylinder and am having trouble getting the push rod disconnected from the pedal. Any suggestions? Pictures maybe of how to release it?

[Gary in NJ]

Cotter pin and clevis. Remove the cotter and push the clevis out.

[Chaseme3]

Hey TBone where did you order a clutch hose from?

[Bonzi Lon]

Try this place, www.BlackDragonAuto.com Clutch Hose, 64-608, 240-280, 70-78, $12.95 + shipping. Ask for their free catalog, many more parts that you can't live without.

Bonzi Lon