93 Miata - clutch acting 'weird' (brake, buy, replace, speeding) - Mazda -Car forums - City-Data Forum

mrs1885 · 05-26-2010, 04:06 PM

I was on the way to work today and the interstate was just locked up. Decided to take the highway. Locked up. Can't win.

But, while sitting in traffic not moving at all, I noticed that when I pushed in the clutch to put the car in first so I could scoot up that very important 2 and a half inches, there was no resistance except for the last couple inches. I had a major panic attack - heart pounding away in my throat. But the car went in gear fine and I was able to take it back out of gear with no issue.

When I was finally able to actually drive, it was the same. Only the last inch of the clutch had any resistance. But once I was driving and shifting gears it was fine all the sudden. Normal resistance the second I pushed it all the way to the floor. Figured, ok something weird went on from just idling, but it's fixed itself, life is grand.

Then trying to get back on the interstate, stuck at a light, go to creep those valuable inches and it did the same thing again. Resistance only in the last inch or so. But again, back on the highway leading to the interstate switching between gears it was normal.

Then I started worrying it might have something to do with first gear, but as I got to the parking garage noticed it wasn't doing it. It seems like the only time I have a problem is when I"m stuck in traffic just not moving. As long as I'm moving - even slowing and speeding right back up - I have no problem.

Any ideas?

JRTurner · 05-26-2010, 04:32 PM

It sounds to me as if you have a clutch slave cylinder on it's way out.

golfgod · 05-26-2010, 04:39 PM

JRTurner hit the nail on the head. When you shift only occassionally, like in heavy traffic it's very noticeable that you're not holding hydraulic pressure. Once you're moving, and snapping through the gears you're pumping the master cylinder enough to build and hold pressure.

If you're not sure of the procedure on this car I (hesitate to send anyone to another site) can heartily recommend "miata dot net". The how to bits on there can walk anyone through simple (and this is a simple) repairs.

Good luck. I much prefer the M1 (89-93) over the newer ones. Barn doors and all.

golfgod

JRTurner · 05-26-2010, 04:51 PM

Not knowing anything about Mazdas in general, I don't know if there are rebuild kits available for those slave cylinders or if you just have to buy a whole new unit. They are easy to replace and the hardest part of it (not really hard buy time consuming) would be bleeding it after it's installed.

Mac_Muz · 05-26-2010, 06:28 PM

I agree the slave is weak, but if you can't get it fixed right away pronto like, change the brake fluid that runs the system. The fluid in part is at fault, and boiling in the excess heat. After some cooling takes place the bubbles are reforming to be fluid.

Bubbles like air can be compressed, a liquid can not.

M3 Mitch · 05-26-2010, 06:52 PM

Agree, this is *probably* the slave, certainly check the fluid level in the master.

My MG-B gave me the same symptoms and it came to me with a new slave cylinder, it was the master cylinder.

Don't put off the fix, it's a cheap easy fix now. If you let it fail completely, you may need a tow, and you can damage the trans shifting if the clutch does not disengage fully.

On some designs, it's better to bleed the slave cylinder after connecting it hydraulically but *before* bolting it up to the transmission/bellhousing.

JRTurner · 05-26-2010, 08:51 PM

I don't believe clutch hydraulics get hot (even in stop and go traffic) like overheated brake calipers can do and create air bubbles.

mrs1885 · 05-27-2010, 08:33 AM

Thanks everyone. Been on MDN since I bought the car GG. I posted there too. Same answer. Just didn't know who to go to when looking for the answer quick.

Today it seems fine. Last night driving home it was fine. So was it just a warning to get something done now?

MDN people are trying to help me through fixing it myself. The idea when I bought the car was so I'd have something simple and basic that I could learn on. I've done little stuff - replacing headlights and taillights, greasing the gears in the window tracks, etc, but nothing big like this. My little heart is racing like crazy!

JRTurner · 05-27-2010, 10:22 AM

It is something that one should expect with a '93 if it's not been done before.

The problem is that it will progressively get worse and possibly could let go all at once.

mrs1885 · 05-27-2010, 10:27 AM

Ok, thanks. Today it gets parked then, until it's fixed.

I will miss it. I hate driving that big bus. *sigh*