How to know when to replace....

[BRGNA8]

....the Clutch master cylinder and the clutch slave cylinder?

Im changing my clutch and flywheel at next service. Just wondering whether the master and slave cylinder is something ill need to look in to as well? If so, what are the symptoms of them needing to be changed?

[— kung fu jesus —]

Yes, I would change both. New clutch, new supporting systems, that is the reasoning. The way to tell if the slave is bad is to gently pull back the rubber boot that covers the slave's actuator (rod that comes out of it and goes to the clutch fork), to see if fluid comes out or is wet with fluid. This is telling you the slave is no longer sealing.

If your slave is good, but you are having difficulty bleeding it, or bad/hard shifts, your master is bad. Other telltale signs your master is bad are fluid in the firewall or area under the master in the engine bay. Sometimes there will be fluid in the back at the firewall where the clutch mechanicals go through the firewall. you would have to peek in the the pedal box area, up under the dash with a flashlight, maybe pull the carpet back a little.

The idea behind replacing them both is to prevent you from destroying your new clutch, including the price of the labor, and gearbox. A clutch master is ~$50-60, the slave about ~$10-20. Additionally, I would replace the rubber clutch line for peace of mind. Your '96 has a rubber line that is 20 years old now. A braided line would be an upgrade.

The symptoms for failing clutch hydraulics are hard gear changes, particularly while stopped (engine running), notchy shifts, soft clutch pedal. If they fail, it will be extremely difficult to move the car because you won't be able to disengage the clutch with the engine running.

[NCGreasemonkey]

On my 95 the rear of the master 'looked' dry. But it was leaking. There is a cover in the hole where it passes through the firewall. You can get the entire set-up from GWR for around $90 incl. the braided line.

[NobleRogue]

The guy I bought my Miata from changed the clutch about a month before I bought it. He did not change the slave and master. I had the car for about two months before the slave blew its seal. I would recommend changing them, for the same reasoning that KFJ gave.

[BRGNA8]

Yes, I would change both. New clutch, new supporting systems, that is the reasoning. The way to tell if the slave is bad is to gently pull back the rubber boot that covers the slave's actuator (rod that comes out of it and goes to the clutch fork), to see if fluid comes out or is wet with fluid. This is telling you the slave is no longer sealing.

If your slave is good, but you are having difficulty bleeding it, or bad/hard shifts, your master is bad. Other telltale signs your master is bad are fluid in the firewall or area under the master in the engine bay. Sometimes there will be fluid in the back at the firewall where the clutch mechanicals go through the firewall. you would have to peek in the the pedal box area, up under the dash with a flashlight, maybe pull the carpet back a little.

The idea behind replacing them both is to prevent you from destroying your new clutch, including the price of the labor, and gearbox. A clutch master is ~$50-60, the slave about ~$10-20. Additionally, I would replace the rubber clutch line for peace of mind. Your '96 has a rubber line that is 20 years old now. A braided line would be an upgrade.

The symptoms for failing clutch hydraulics are hard gear changes, particularly while stopped (engine running), notchy shifts, soft clutch pedal. If they fail, it will be extremely difficult to move the car because you won't be able to disengage the clutch with the engine running.

On my 95 the rear of the master 'looked' dry. But it was leaking. There is a cover in the hole where it passes through the firewall. You can get the entire set-up from GWR for around $90 incl. the braided line.

The guy I bought my Miata from changed the clutch about a month before I bought it. He did not change the slave and master. I had the car for about two months before the slave blew its seal. I would recommend changing them, for the same reasoning that KFJ gave.

Thanks a lot guys! Was able to get a good deal for a brand new genuine OEM master and slave. Looks like its one more thing to add to the list of stuff that needs to be done!

Cheers fellas!

[NobleRogue]

lol "Just one more thing to add to the list". Sounds like something I have been saying since day 1. It's fun though when you are actually making improvements instead of just fixing.

[BRGNA8]

lol "Just one more thing to add to the list". Sounds like something I have been saying since day 1. It's fun though when you are actually making improvements instead of just fixing.

It's a vicious neverending cycle. hahaha! But yes it is fun, you're right