Clutch problem... help, please!

I have a 2006 Mazda 6 with 104k on it. The clutch started sticking a couple weeks ago right where it would engage into gear, and I’d have to use my foot to pop it back up. It only happened here and there until finally, it stuck to the floor and became very difficult, if not impossible, to get out of gear. So everywhere I looked, it seemed that the slave cylinder was the culprit. I got a new one at AutoZone, replaced it yesterday, and the car ran great last night and this morning.

Then, this afternoon, in one 10 mile trip, it went back to the original problem. Stuck with every gear change, then stuck to the floor after I pushed it in and darn near wouldn’t come out of gear. What in the world could be the problem?

Thanks!

The problem is probably with the clutch master cylinder.

Let me ask you this. Does this problem occur when it’s hot out and the engine is hot? If so, the problem is with the master cylinder.

Tester

It did seem to happen after the car was warmed up. Only about 70 out today though.

Is the Master cylinder much harder to replace than the slave?

It’s a little harder. You have to get under the dash to remove the clutch pedal fork from the master cylinder rod. Then it’s just a matter of removing the hydraulic line from the master cylinder and then remove the two nuts that secure the master cylinder to the firewall.

Hint: Thread the hydraulic line into the new master cylinder prior to installing the mounting nuts. Less likely chance of cross-threading the hydraulic line into the new master cylinder.

Tester

Hopefully I can find a YouTube video so I know I’m getting the right thing. I think bleeding it is the part that I’m most uneasy about. I think I did it right on the slave, but that’s more hope than anything. That brings a question - would not bleeding the slave right (if I didn’t do it right) cause this same problem?

Assuming not, or assuming I did it right, on the master cylinder - Would you suggest getting a replace master cylinder with the reservoir or just reusing the old one?

Also (sorry for all the posts…) I just found a guide and noticed in the workshop manual when it comes to removing the master cylinder, it does not say anything about going into the car to remove the clutch pedal fork. Is it not necessary in some cars or, if it is, do you have any suggestions on some place I can look to see what it looks like/find out what exactly to do? Thanks for all the help!

The reservior just holds the fluid. The master cylinder does the work.

If you bled the clutch hydraulic system after replacing the slave cylinder, you can bleed the hydraulic system after replacing the master cylinder.

Besides, when a slave cylinder leaks it leaks externally. So you see hydraulic fluid on the ground. A master cylinder leaks internally and you don’t see hydraulic fluid on the ground.

Tester

But if I did happen to bleed it improperly, or not get all the air out, it wouldn’t be possible that this is what’s causing the problem?

And if it turns out I did replace that slave without needing to, is there any solace that at 100k+ it may have needed to be done in the future anyway? lol

Have you checked the pedal mechanism under the dashboard? If there is play in the fulcrum, the pedal might be the issue.

In my experience, it’s usually a good idea to replace both the master and slave cylinders at the same time to rule them both out, so I wouldn’t give another thought as to whether replacing the slave cylinder was worth the trouble.

+1 to Whitey’s post.

Both cyliners are very similar, and if the seal in one is worn out, the other is generally in about the same shape.

One other thing that happens is that if you have bypass in one cylinder to where you’re pushing the hydraulics beyond the place in the cylinder where they usually go, you can drive the seal into an area where it can begin to stick.

+2 for @Whitey. I’ll just add one comment here…I never replace the slave cylinder without replacing the clutch master cylinder and vice versa. It’s one of those “been there…done that” kind of situations.

Changing a slave cylinder is like losing fake friends; you’re no worse off.

thanks all. at least I don’t feel bad about doing the slave cylinder (and it was quite the learning experience. one of those fun-after-the-fact thing!)

Question now… I was under the hood and took off the mounting bolt off the master. I removed the line from the master to the reservoir and also undid the nut with the stiff line that goes into the bottom (sorry, I don’t know proper terms for the parts). So with everything under the hood disconnected, I went under the dash. The rod and the nut are the ones right behind the clutch, right? If so… how in the heck do I get those off? There’s no room for anything under there. Couldn’t get a ratchet or wrench or anything in there. So… what’s the secret to getting these suckers out of there?

The rod attaches to the backside of the clutch pedal, about 2-3" down from the hinge point. Often is is just a clevis pin and hairpin retainer or something like that.

I ended up being able to get a ratchet up to the nut on the bolt and undo that, so I didn’t have to pull anything out of the clutch itself. Hopefully that was ok.

After my one-hour-turned-all-day task, I think I managed to get everything back together. I haven’t put in the battery back in yet because I want to make sure it’s bled first. Do I do this the same way as the slave cylinder or is there an easier way?

Thanks everyone for all the advice!