About one year ago I had the same problem, took it too a mechanic and he replaced the clutch master cylinder. It worked fine up until about three days ago. I do not want to keep taking it back to the guy so he can charge me a couple hundred bucks a year to fix the same problem.
1 - is this something I might be able to fix myself, or with help?
2 - If not; is there a good place anyone could recommend me taking it to that will do it right?

The same mechanic fixed my exhaust leak that has also since re-sprung. So while Anthonys in Milford may have been good at fixing Jeeps, don't take your Z there =0(.

the clutch system is pretty easy, it's only 3 things .

The clutch master cylinder,
The clutch slave cylinder,
and pressure lines.

first, open the hood, and see if you have fluid in the clutch reservoir on the fire wall, directly in front of the the clutch pedal. If you don't have fluid, then you have a leak, find the leak, and that will fix the problem. If you have fluid, then that means that the master cylinder is shot or the slave cylinder, fluid is just bypassing the o-rings. It's always good to replace both at the same time, and by the way it's sounds, the mechanic probably just changed one, and it's only a matter of time when the other one will go. Rebuilt Masters and slaves are cheap at Autozone, cheaper if you order them online thru autozone, and while your at it, order the flexible pressure line from you hard line to the slave cylinder on the transmission. Age is very bad for them due to the heat of the engine, the oils and weathering that they take...the best lines to get are the stainless steel wrapped flex lines, since they last longer and the keep the pressure in the line to add pressure to the slave cylinder instead of trying to balloon up on you and making the line it's self absorb the pressure from the master.

And once you get the parts, jack up the car, you will be done replacing them in about an hour, and then you can move on to the bleeding of them. Some people bench bleed, but that mainly for the brake master cylinder, clutch MC's like to be gravity bled, and then reverse bled....an easy process.

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Also Known As Clayton Pace

Get ahold of Rich at RDZ right away! (Rich@RDZ.Com)

These guys are Pros, focus only on Z cars, and are one of our Club's sponsors. Go to our Homepage and look on the left margin. In the column of our sponsors, press on RDZ to send them an EMail. You can also send Rich a Private Message by finding his name in our Memberlist (#13), then pressing his "PM" button.

They enjoy an excellent reputation, really know their stuff, and are totally Z-oriented. They're busy almost constantly, but they make time to read their mail from here, so you should get a response as soon as one of them has clean hands.

You can also hope for a response from AirJockie, Tom Wasney or Paul Mackin.

Frank T
MbrshpDir
(Frank@CTZCC.Com)

$43 not including shipping, for the slave and master at autozone, $18 + shipping for the clutch hose from MSA. http://www.thezstore.com/page/TZS/PROD/PCC05/21-2172

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Also Known As Clayton Pace

So do i have to replace the MC again because the SC wasnt replaced at the same time? Or are you just saying it should have been done that way in the first place. If i should replace them both I will, i just want it done right.
Also, will i need any special tools to get the job done?

at the price they are, it's better to do them at the same time.

if the slave wasn't replace, and the MC was, there is a possibility that crud, moisture, and old o-ring shavings might have worked it's way back up to the master. There is also the high possibility that you got a poorly rebuilt MC as well, they are just like alternators, sometimes you get decently rebuilt ones that will last a few years, or you get a poorly re-built one that will last a few hours.

As for tools, just a bowl to catch the old fluid, some rags, needle nose plyers to pull the circlip from the pin holding the pedal, a few metric wrenches, and a hose connected to a thawed out water faucet and some degreaser to wash away any brake fluid you might get on the car... brake fluid is what is normally used for the clutch system, and if it touches paint, it will act like a paint stripper if left on an area too long. No paint=bare metal+moisture+time=rust. And you'll have to jack the car up or drive it up some ramps.

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Also Known As Clayton Pace

Personal opinion here ~ if you can afford it and have time, change them both together. It's a simple system and not terribly complicated, if you have someone to help you bleed the system properly.

I don't recall the size of all the hardware but when I did it last time all I used was my standard metric wrenches from my toolbox, and don't recall having to buy anything special.

I do recall it helped me to remember where the Slave Cylinder adjustment rod was on the old unit. It had taken me several experimental tries to find the "sweet spot" where the clutch didn't slip and gave me a happy travel distance. You might want to make note (or a digi pic) of where your adjustment rod sits before you start pulling stuff off, just to make sure the new installation get adjusted quickly. Others who have done this since the 1980s might have better advice.

*(BEAR IN MIND my work was done on my 1970 240Z ~ may have become more complicated for your 300ZX).

Frank

all nissan systems stayed the same...even the R34 trany that I got has the same looking slave cylinder as the 74 260Z...

and bleeding the trany is really a one person job.


fill res, open the bleeder on the slave, wait for fluid to pour out in a steady drip, close bleeder, and with your hand push the slave in a few times, let it fill...and watch for bubbles in the res. done.

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Also Known As Clayton Pace

Ohh god...I did a tech post

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Also Known As Clayton Pace

Thanks.. thats a great peice of advice Frank, that would have drove me nuts ha. Thanks to both of you for your knowledge, I'll let you know how it goes.

some more good news - she doesnt have to be my daily driver anymore so no more snow / wind / rain / ice for her! I'm picking up one of two jeeps im looking at over the next few days and she'll be kept warm and cozy in one of my garage bays. Life is SWEET!

Thanks again for the info i'll let you know how it turns out...

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Best 500 bucks I've ever spent!

Before you start replacing everything, you should figure out what's wrong. Your MC should have lasted much longer than a year, but it's possible it went bad. More likely though is that the slave went bad. If it's the slave, it's a waste of time and money to replace a one-year-old MC.
Check the fluid level in the MC. If it's low, refill it and bleed it,(you MUST properly bleed it in order to diagnose it!) then find out where it's leaking from. A bad slave cylinder ALWAYS leaks visibly, as does the hydraulic line. If you can't find a leak but are continuing to lose fluid, the MC is bad, and it's leaking into your footwell.
If you are NOT losing fluid, then either the MC is bad or there has been a mechanical failure inside the clutch housing, such as a broken shifter fork.You need to go under the car and visually confirm whether the slave is moving the shifter fork as the clutch is depressed. If the slave doesn't move when the clutch is depressed, the MC is bad. If the slave moves the fork but the fork does not push the slave back when the pedal is released, then you have to pull the tranny and find out what's wrong. The pressure plate spring is what forces the clutch pedal back up when you release it, and if the fork is bad then the pedal stays down.
If I had to gamble, I would definitely bet that your slave has gone bad, has allowed the fluid to leak out until the MC is empty, and now there is no hydraulic fluid to force your pedal back up. Second guess would be bad MC and third would be a broken clutch fork pivot pin.

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71 on a rotisserie, two more in pieces in my shed...and a 69 1600 waiting for me to get to it

Sounds like the voice of experience!

I love this Club!

All excellent advice guys. If nothing seems to solve it, please feel free to contact me. 203-395-2452

Likewise, feel free to give me a call. I'm right down the street from Rich and specialize in Z31's. I keep a well stocked garage full of new/reman parts at all times. I've got a complete clutch master/slave cyl setup down there as we speak, ready to get installed in your car for a reasonable fee. Also a good time to do a clutch damper delete. Improves clutch pedal feel and eliminates a problematic Nissan part. At $10 more for the part, hard to pass up! (914)912-6529

Well,since all has been said,there is one more thing,but never saw it on a Z car,but thought I'd add this in........a flexing clutch pedal bracket, or even cracked. Mostly on Toyota trucks. Pedal won't go to the floor, but can't engage it into gear. Maybe this will help someone someday.