Today’s question has to do with clutches. The title is a little misleading since some vehicles it is normal operating procedure to double-clutch to change gears.
As I was driving to work today I had to pump the clutch to get the Corolla to change gears. When I popped the hood there was no fluid in the clutch master cylinder reservoir. Got any ideas as to what happened?
My questions:
What vehicle? 1996 Toyota Corolla LX
Did you notice any fluid on the carpet under your feet? No, since it’s been snowy and wet around here.
NOTE: You can check the carpet just below where the clutch master cylinder comes through the firewall to attach to the clutch pedal. Brake fluid will make your fingers very slippery.
Did you notice any fluid on the floor of your garage? With all the snow it is hard to tell.
Diagnosis by phone: This one’s a toss up. It could be either the master cylinder, the slave cylinder, or the clutch flex line that is leaking. Without a little more hands on diagnosis this one is unknown. Just another example of why we don’t diagnose over the phone.
Final diagnosis: Well, we pulled this one in with some creative clutch acrobatics and did a diagnosis. Slave cylinder is dry on the outside with no evidence of a leak in or around it. Followed the clutch line up to the next possible place, the flex line. That’s dry and clean on the outside as well. Next! We then followed the clutch line from the flex line to the master cylinder. No leaks on the hard lines. There’s some fluid on the outside and below the master cylinder, but the owner had said that he had spilled some when topping the fluid off just a day or so ago. Ok, so this is a possibility, but we can’t be sure until cleaning it off and driving it for a while. Ok, so to the inside of the vehicle. After playing the contortionist to see up under the dash I find that there is a light film of oil on the clutch bracket. What I expected to see was a that the rubber seal on the clutch master piston rod was wet and that there was an active leak on the floor. There was nothing of the sort. So, we cleaned up the portions that were possible leaks, bled the lines of any air pockets, topped off the fluid and did a couple mile test drive. It’s back to normal operating condition. So we sent it away and asked the owner to check back in a week to see if we could see any fluid leak.