Good day all. The clutch in my '84 GSL is acting wonky as of yesterday - it seems to not disengage all the way every time.

The first thing I'm suspiscious of is the clutch master/slave cylinders. The fluid level is OK, so I don't think that they're leaking, but the seals could of course be shot.

A new set is ~$200CDN from Mazda, but the master is on back-order - could take weeks to arrive. The warehouse does, however, have rebuild kits in stock, ~$40 for the pair.

Questions:

1) Is there any reason why I wouldn't just do the rebuild? Do the bores etc. on these things actually go bad, or is it generally going to be just the seals etc. that's included with the rebuild kits? Assume that I do not assign any value to my time and frustration.

2) What are the other possible candidates for causing this kind of problem, and how do I trouble-shoot to narrow it down? I'm thinking that it could be the throw-out bearing, or a bushing on the actuator fork, etc.

The clutch had a similar problem about 3 years/ 30,000 kms ago, and was replaced with a copper-lined competition friction element. Beyond that, though, I don't know what all was done, because I trusted that shop implicitly at the time and have since had a bad falling-out with them.

Thanks in advance for any info or insight,

 

BTW - the engine is an '88 13B, but I am still using the rest of the '84 GSL driveline that used to live behind the 12A.

Thanks,

 

Since your fluid level is not going down, I would suspect that the master cylinder is recirculating, rather than the slave cylinder as the slave cylinders typically leak when they go. Yes, they can be rebuilt (I've rebuilt both master and slave cylinders to good effect) IF the bores are not pitted. You want to get the bore really smooth, I use 600 grit SC paper wrapped around my finger (yes, my fingers are skinny). To answer the second part of your question, if the pilot bearing in the rearward end of the eccentric shaft starts acting up, it will "grab" the tranny's input shaft and make it hard to get in gear. I had the same problem with my '80. When I seperated the tranny and the motor, all the roller needles fell right out in my eye. It was pretty obvious at that point what the problem was, lol.

 

Thanks for the info! Any thoughts on how I can tell if the prob is with the pilot bearing vs. one or both of the cylinders?

Thanks,

 

I agree with Wankelguy, a rebuild can be done effectively enough to make it worth while, not just to be considered a stop-gap, as long as you take the little bit of extra time to do it right.

Brian

 

If the slave cylinder pushrod is travelling fully, it's a good bet that the master and slave cylinder are okay.
A bad throwout (release) bearing usually makes noise when the transmission is in neutral and the clutch is engaged, then the noise goes away when you push on the clutch pedal. A bad pilot bearing can cause the input shaft bearing to get noisy due to the input shaft not being supported properly at it's forward end. Then the tranny will be noisy when it's in neutral. When my pilot bearing went out, I would be unable to get it in first gear after stopping at a light. This only happened sporadically, and oddly enough, seemed to happen more when I was stopped on a hill. I would have to turn off the motor, put it in gear, push in the clutch, restart the motor then everything would be fine and dandy until it happened again.

 

This REALLY sounds like what I'm up against. I am planning to drastically decrease the amount that I drive the car soon, and to yank the motor for some more mods this spring. I think I may keep pressing my luck using that same trick (it also worked for me this morning) until then if the check for the master/slave suggests that they're working right.

Thanks a million!

 

Both the master and slave cylinders are really easy to rebuild. If the bores are smooth with no pits, then all there is to it is replacing the seals.

Another thing you might wanna check, the bolts that hold my slave down stripped out of the tranny. it still worked, but it was a bear to get in first and shift the rest of the gears as well.

Have someone press the clutch and look at the slave, if the bolts are stripped, then the slave will rock back.

The easy fix for this till the next time you pull the tranny and can helicoil them is just get the next longer bolts and put those in it (You will probably need a couple washers under the bolt heads since too long bolts will touch the flyweel and your engine will be locked up solid... voice of expierience).