Clutch repairs can be quite simple
On The Road AgainMarch 8, 2012 | 4,252 views | Post a comment
This past week, I had a customer complain about the clutch in their Mazda. The clutch pedal went to the floor too easily, and he couldn’t get the car into gear. Most of the time, when you can feel the problem in the clutch pedal itself, it is a hydraulic issue, not a worn clutch.
A quick inspection revealed fluid leaking out of the slave cylinder, so it needed to be replaced and bled out. For $20 in parts, some fluid, and labor, he was all fixed up again.
Hydraulic clutches are relatively simple, they use a clutch master cylinder, a fluid line, and the slave cylinder. When the pedal is pushed down, it forces fluid into the slave, and the clutch fork is moved over releasing the clutch. If seals begin to leak, fluid can bypass and/or leak, and once the fluid leaks out, air enters the system, and it fails.
On certain vehicles, the master line and slave are one piece and have to be purchased as a unit, driving up the repair costs. Once these components are replaced, the system has to be bled to remove all of the air from the system. Since air can be compressed and hydraulic fluid cannot, the pedal will feel spongy and inoperative until the air is removed.
While all this sounds simple, some manufacturers managed to make things difficult by installing the slave cylinder inside the transmission’s bell housing, as opposed to an external mounting location. On these vehicles, the transmission must be removed to access the slave cylinder. Of course, once the transmission is removed, it makes good sense to go ahead and replace the clutch while the transmission is out. As you might imagine, a simple repair turns into a very costly one in both parts and labor.
This is why it makes perfect sense not to use rebuilt hydraulic parts when doing a slave cylinder repair. Even if a new slave is double the money, and they rarely are, it is cheap insurance to buy new. Any part can fail prematurely, but your chances are a lot higher for a long-term fix with new parts.
Send your vehicle maintenance questions to Jeff Deines. Email nkilbey-smith@wcn-online, putting “OTRA Question” in the subject line.