Chattering and Spongy Clutch: Related?
 

Hello, I am having problems with my clutch. I have searched a bit, don't worry.

These are the two symptoms:

1. My clutch has been slightly chattering ever since I replaced my clutch with a stock mazda clutch (mistake) a year ago. It was nothing that a little more effort with the clutch couldn't control. But now, it is starting to get worse. Almost every 1st gear start has a chattering feel. . .

2. Also recently, my clutch pedal has been feeling spongy. Like if I hold it down at a light for a long time, the clutch will engage earlier and it doesn't come back all the way w/o pumping it.


My question is: Could these symptoms be related? Could it be the master cylinder for both, or something like that?


Any help or advice would be greatly apprecited.

-Charles

1988, n/a

i dont know what to tell you about your first problem but i can help you on the second problem.

your second problem is that either your clutch master cylinder bushing is torn or your clutch slave cylinder bushing is torn. i did a writeup on hoe to rebuild both of those. the total cost of the rebuild was 24 bucks and 1.5 hours your time. here is the link for the writeup

https://www.rx7club.com/2nd-gen-archive-72/clutch-master-slave-cylinder-%2Awriteup%2A-532869/

Chattering can be contaminated friction plates, burned flywheel surface from too much slippage or a bunch of other causes. One of which could be your slave cylinder too. It might have a leak or need to be air bled. Then check the master cylinder while you're at it. Don't neglect to check your pedal freeplay as per FSM.

Oh yeah, I forgot to mention that the brake fluid has never leaked or gone lower in the ma. cylinder. . .

Then it might very well be the rubber pistons in either or both the master and slave cylinder.

did you have your flywheel turned when you replaced your clutch? that could cause a chatter. as for the other problem sounds like your slave and or master cylinder need to be rebuilt or replaced. those can magnify a chatter when bad.

Ok thanks for the help... I'll get back on how it turns out.

My clutch chatters after I've been driving for a while (heated flywheel\clutch?) when starting from a s top.
It's silky smooth for the first half hour of driving.

Same thing happen to you?

I think it does... I usually let the car warm up first before I drive it fast. . . It's very annoying.

~Amazing Results~
 

Ok, after hearing everything and searching, I decided to go ahead and just bleed the clutch before anything else. The fluid in my reservoir was pretty grimy, almost grainy. . .



1. First, I pumped out most of the old fluid from the reservoir and filled it with new Castrol fluid. I did this a few times to dilute the old fluid...

2. Next, I bleed the system through several times. In other words, I had to refill the reservoir a few times. When I was done, the clutch fluid was MUCH cleaner!



That is all I did! I then drove the car...Wow, what a difference. I let it fully warm up, and just drove, and it gave me NO more problems for the whole 35 min drive. I couldn't even feel the chattering feel anymore, whereas before I couldn't even start moving on a slight hill w/o major "chattering'.

I have a pretty steep driveway and usually I have to let the clutch out before I start going up the hill. Tonight, I let the clutch slip slightly all the way up the driveway with no chattering feel. Wow.




I know that I will probably have to replace/rebuild my master or slave cylinder, but until then this will hopefully get the job done!