On 83' the clutch has slowly declined to where it loses the pedal after holding it down (say 30 secs) or when I am driving I will have to pump it to gain function. Then it works until I have to pump again next few shifts. Tried bleeding the slave both with pumping the clutch and closing the the valve in rotation and by pressure bleeding. Gained nothing. Before I replace one or the other, how do I determine which is bad... the slave or the master cylinder?

 

If there is no fluid leaking around the slave, I would think it was the master. I would just do both because they are cheap.

 

It doesn't matter which is bad. They usually fail close together. Since they're hydraulic parts, if both are old and you replace the bad one with a good one, then it puts more stress on the remaining part.

Do the pair at the same time, it's worth going through the trouble only once, then you're sure you've got the problem and don't have to deal with it again later

Jon

 

If you happen to order the stuff from MazdaTrix, buy the SS braided line instead of the rubber one as the SS braided one is cheaper and better.

 

Think I will go ahead and replace both. Any special warnings or advice to offer in changing out parts (things that are unusually difficult or tricky)?

 

As they say, replace all 3 parts. That hose has an uncanny way of leaking without showing it!

It's difficult to bleed the system after installation. Make things easier for yourself by loading the cylinders with fluid before you install them. Even so you might find yourself cussing when trying to bleed, You may have to improvise a power bleeder or install a checkvalve nipple.

 

You might want to remove the drivers seat. It makes it a lot easier to get at the master cylinder mounting nuts. The only slightly difficult part is getting the upper nut off the master cylinder stud. Do a search. There are several writeups with easier ways to do it.

 

These two are usually two of the biggest Pain-In-The-*** parts to change

For the Master:

Take out the driver's seat and lay on your back on the floor. You'll swear at it quite a bit trying to get the two nuts out. It helps to take out the "rod" that goes from the top of the pedal into the clutch master. It's held in place by a pin and c-clip. Once it's out of the way you have a bit more room to work with.

Slave Cylinder:

If you've got the stock rat's nest, it's going to be almost impossible. You pretty much have to take pictures, document, and (at least temporarily) remove the rat's nest to get to one of the bolts. The other you'll need a 10" extender and a deep socket and some patience.

Just keep at it until it's done. Try not to get discouraged. They *are* tricky, which is why it should all be done at once.

Jon