Today while performing a back-and-fill maneuver required to get out of my garage and down my driveway, the clutch started acting up. It failed to fully disengage and at one point the car was creeping forward with the clutch pedal fully depressed. The pedal feel and stroke is normal and the return seems normal too. I shut down the engine and checked the fluid level; its normal. There are no obvious leaks and my garage floor remains spotless. I strongly suspect the clutch master cylinder is at fault. The symptoms are intermittent; therefore, theyre a bit tricky to fully diagnose. I think fluid could be bypassing the piston or perhaps there is a piece of dirt in one of the ports. At one point I got the feeling the clutch was bleeding down, but later it seemed that it simply didnt produce a full stroke. There is no loss of fluid, so I hope the slave cylinder is OK. Before I replace the master cylinder, which I hope is the faulty part; I wanted to check with other Ferrari owners. Has any else suffered this problem? Changing the master cylinder is dead simple. But Im afraid changing the slave cylinder means a trip to a shop, at least for me. Comments?
Everything you describe would lead me to suspect the master cylinder but I'd still advise you to bleed the clutch circuit before you do anything more. Careful with the bleed nipple - it's very easy to over tighten it and break the metal block. Check also the routing of the supply pipe from the reservoir to the cylinder - mine had a kink in it which caused fluid starvation issues from time to time resulting in a very odd feeling at the pedal occasionally. There's not an awful lot of chat about these cylinders failing from what I've noticed over my years of trawling around here. Best of luck.
Yesterday I was all set to ignore your advice and just go ahead and change the master cylinder. The first thing I did was to be sure I could reach the bleeder from the top of the engine compartment. Answer: Yes, and it's easy. Why the manual advises gaining access from below is a mystery to me. As I started draining the fluid, I noticed a LOT of air coming out of the bleeder and I quickly changed my mind about changing the clutch pump. I flushed out all the old fluid and carefully bled the system. That produced a nice feeling clutch and some preliminary driving tests indicate that you may have been entirely correct. At the moment the new clutch pump is still in the box and my car is driving well. Since the original problem was intermittent, the jury is still out, but I hope the problem is solved. Thanks for your advice.
Well, it turned out to be wishful thinking. The clutch action did improve with bleeding, but I encountered another bout of decreasing clutch pressure when "backing and filling" to get out of my Italian sized garage without hitting my fence or gate. When the clutch started engaging with the pedal fully depressed, it added to the challenge, that's for sure. The solution, as I suspected all along, was changing the master cylinder. I'm convinced that my old clutch pump was leaking internally allowing the clutch to gradually engage if the pedal were held down for extended periods of time. It also produced inconsistent clutch bite points when shifting which I think depended on how rapidly I depressed the clutch pedal. That made some shifts seem amateurish. Now, with the new pump, not only does the actual shifter move out of one gear and into the next more smoothly, the consistent bite point makes matching throttle position with the clutch pedal much easier so that my Ferrari no longer sounds like it's being driven by a high school drivers-education student. I've posted my "lessons learned" elsewhere.
