Clutch Master Cylinders... different from 73 to 78?

[Guest 73Turbo240z]

I was trying to bleed the brakes and clutch tonight in efforts of preparing for driving the car this weekend.

 

In bleeding the clutch things didn't feel quite right, so as i'm tucked under the dash checking for interference points, i notice the clutch pedal is stopping a good full inch before the actual "stop pad" on the steering column mount.

 

This would account for another roughly 4" of actual pedal travel i figure... i checked my thread on the rod itself, i'm @ the very end of it.

 

I haven't dug through my reciepts to see which i got yet, but i'm assuming i got a 240z clutch master cylinder, would seem logical, just to be safe i cross referenced my 73 vs a 78 on http://www.oriellyauto.com... there house brand uses the same P/N, other guys don't, so i'm not sure what is going on here.

 

The car is a 73' 240z, i'm pretty sure i purchased a 73' 240z clutch master, so i dunno what the deal is. Either way the pedal "feel" is telling me that there isn't enough pressure to do the job, so before i go dropping it on the ground to find out the old fashioned way, figured i'd ask here 1st.

 

I'm running the 73' 240z clutch master, 73' 240z clutch slave, and a earls braided stainless clutch line where stock rubberline use to be.

[Guest 73Turbo240z]

anyone?

[540z]

Hi,

You mentioned that you have some distance between where the pedal stops moving and the actual pedal stop on the floor. Have you replaced the clutch master or messed with the clevis that attaches the pedal to the master's actuator rod?

You also mentioned that you have the slave cylinder's adjusting nut run out almost to the end. Is there any end play between the adjusting nut and the hole in the clutch fork?

Let's start here first,

TR

[Guest 73Turbo240z]

Hi' date='

You mentioned that you have some distance between where the pedal stops moving and the actual pedal stop on the floor. Have you replaced the clutch master or messed with the clevis that attaches the pedal to the master's actuator rod?

You also mentioned that you have the slave cylinder's adjusting nut run out almost to the end. Is there any end play between the adjusting nut and the hole in the clutch fork?

Let's start here first,

TR[/quote']

 

 

other way around, i've run out the "clevis" (guessing thats the technical name for the u shaped metal bracket) to the max on the actuator rod on the CMS... i'll get shots of both and host them here shortly.

[540z]

Let me backtrack per my previous post. I misread what you were saying. I thought you replaced the slave cylinder. I can empathize with your problem about the clutch master as I had to replace 2 P.O.S.'s that I got from aftermarket manufacturers. As far as pedal clearance goes, you should have about 8" of distance from the front of the pedal to the stop. Adjust the clevis rod accordingly to get this.

[Guest 73Turbo240z]

 

as you can see... the rod is maxed out, i can adjust the bump stop to hit it probally, but that still doesn't change the fact it doesn't see right ya know?

 

i'm going to climb under there w/ a ruler and measure the current pedal distance, kinda hard to do @ 220 and 6'0" but i want this damn thing to run.

 

only other thing i can think to try before pulling it out and heading back to the store pissed is start the car while it's in the air and try to run it from neutral to 1st, 2nd, etc... just makes me nervous doing it w/ the car in the air on stands.

[Guest 73Turbo240z]

quick measure shows 5" from firewall bump stop to very front leading edge of pedal, i'd have taken a photo but the battery has died.

[540z]

I wouldn't advise you to start and run your vehicle on stands, just don't. If you have to start it, put it on all 4 wheels. Also, I wouldn't drive it if the bump stop under the dash can't reach far enough to keep the pedal return spring from eventually yanking the rod out of the back of the clutch master cylinder.

Is it possible that the rod was compressed into the cylinder before installation or before you filled it with fluid? Press on the rubber boot of the actuator rod with your finger. Did any oil come out?

Let's take a look at the rest of the problem. Go look at the other end of the clutch master cylinder in the engine compartment. Does it look the same as the old part? Are there any markings on the casting? Measure the old part's rod and compare it to the new one. Sorry to sound like I'm just picking up on the obvious, but you never know.

I just picked up my Vic Brit catalog, and they list the same clutch m/c for the years 70-78.

Oh, by the way, I am about 5'5" and 135, so I have no problem fitting under the dash of my '72.

[Guest tony78_280z]

When I need to find out if a part from one year will fit another year, I check the British Vicotria (or is it Victoria British? No that is Victorias Secret... Anyhow) and see what years they list for the part.

[blueovalz]

I guess I'm missing the obvious (but I read these postings several times), but have you considered adjusting the clevis back toward the middle of the threaded portion? My rationale is this:

 

Your piston is pushed into the MC too far (due to the cleavis being adjusted to the very end of the rod - too far out) so that the piston is hitting the end of the bore and preventing any further pedal travel. When this is done, and the pedal is retracted, the piston is only drawn partway back, and hence will not draw the proper fluid for the next stroke. But this would mean you would have great difficulty in bleeding the clutch system. I would adjust the clevis so that the pushrod has no pressure on it at all when the pedal is retracted and resting against the stop. Then with no more that perhaps 1/2" of pedal travel, the pushrod should start pushing the piston into the bore.