360 clutch pump change….. Lessons learned.

They say a picture is worth 1000 words, but in the 360 workshop manual they’re only worth 500 words because Ferrari didn’t publish the whole truth. The photos are just fine except that they make the clutch master cylinder remove-and-replace procedure look like child’s play. They omit all the stuff in the way and don’t show the limited access room which makes it a challenge, especially for old fat guys like me.

It should be no surprise to anyone that things are packed in pretty tightly and it’s nearly impossible to get any kind of wrench on some of the nuts and bolts, much less a torque wrench. Don’t be fooled by the pictures. The job isn’t beyond the hobby mechanic’s ability, but don’t think you can do it in a half hour.

The procedure is straight forward enough and I don’t intend to write a step-by-step guide, but I will try to give a few tips to supplement the digital shop manual available for download.

Buy the appropriate fluid, in my case DOT 4. You may need less than half a liter, but I used more, so it doesn’t make sense to buy a lot of small bottles. Use plenty of paper towels and rubber mechanics gloves You don’t want brake fluid on anything, including you, but it’s almost impossible to avoid some drips and leaks, so position wads of paper towels every place. Paper towels might also catch any washers or parts you might drop and keep them out of the bilge.

I used my suction bleeder pump to drain the reservoir. Expect a little spill when you disconnect the rubber hose connecting the reservoir to the pump. Plug the end of the hose to stop any further leaks and don’t drop the little hose clamp. Then dismount the reservoir and move it out of the way, but you can leave the brake hoses connected.
The clutch pump bottom mounting nut is easy to get a socket on if you have an extension, but the upper mounting nut need some fancy open-end wrench work. You’ll be turning one flat at a time. Don’t worry, you can do it but don’t round off the nut by being sloppy.
I had to slide the old pump part way out of the pedal box before I could get a wrench on the banjo fitting associated with the hard line running aft to the slave unit. Again, don’t be fooled by the photos. It’s a tough one and you should support the pipe and pump with one hand when breaking the banjo fitting loose to avoid damaging the rigid pipe.

When you disconnect the clevis from the clutch pedal, you should pay attention to how the washers and plastic shims are positioned on the fulcrum bolt. Once again, don’t be fooled by the photographs. You’ll be working partially blind and you’ll also practice your ability to operate two wrenches with one hand. Cursing helps. If you’re …… um ……. let’s say a “full sized man”, like me, you will also experience a certain amount of pain.

Now you can remove the old pump with the clevis attached. I measured the distance from the pump mounting flange and the center of the hole in the clevis so I could duplicate the operating length when I transferred the clevis to the new pump operating rod.
I was unable to bleed the system using my suction bleeder because when I cracked the bleeder screw, the vacuum sucked air around the threads. Grease didn’t solve the problem. Because there isn’t a non-return valve in the typical hydraulic clutch system, you may not be able to bleed it by pumping the pedal either. So NOW is the time to remove the bleeder screw and put some Teflon tape on the threads being particularly careful to do a neat job so that no Teflon tape can enter the hydraulic system. If you wait until you discover you can’t bleed the system (like I did) you will waste some additional brake fluid before the job is done.

Make sure you support the pump and hard line when you tighten the banjo fitting and don’t drop the copper washers.

Connecting the clevis to the pedal using the fulcrum bolt, along with all the shims and washers, is another cursing-fest, but if I can do it, you can do it.

Read the procedure for setting the pedal height and stroke carefully but realize what you’re doing. There is no mention about setting the desired clearance between the pedal and the piston, something most folks call “clevis play”. When I matched the clutch pedal height to the brake pedal, there was a few millimeters of “clevis play”. Perhaps a tad more than I would like, but at least there was some. This is not the same thing as “overall clutch play” in a conventional system where the throw out bearing must not continuously contact the diaphragm springs.

After adjusting the upper stop bolt as outlined in the shop manual and giving it the recommended “one additional turn”, all my clevis play disappeared. This is acceptable, all other things being equal, but it makes me nervous. Backing off a quarter turn on the upper stop bolt gave me barely one millimeter of clevis play, insuring that the piston is fully retracted. I’m not a certified Ferrari mechanic, but I’ve worked on plenty of hydraulic clutch and brake systems. It’s important that the clutch pump is not advanced far enough to close the intake port with the pedal at rest and a tiny bit of clevis play will guard against this. This translates into a very small and certainly not objectionable amount of pedal free play, but it gives me confidence that my clutch will operate properly with the intake port open to the reservoir when my foot is off the clutch. Zero clevis play is OK and even a tiny bit of preload is OK, but if you go a little too far you may experience “clutch pump up” when the fluid gets warm and your first indication will be a slipping clutch. Why the shop manual doesn’t mention this, I don’t know.

I don’t know how important the stroke adjustment is, but I set mine carefully as outlined in the shop manual since the specification was given to the tenth of a millimeter.

Bleeding the system from the aft bleeder block is pretty simple if you have one of those cheap suction pump systems, but I couldn’t do it without first wrapping Teflon tape on the bleeder screw to prevent sucking air. I can easily reach mine from the top, so no need to remove the belly pan. I don’t understand why the manual says to access the bleeder from the bottom. Again, a big wad of paper towels will catch the inevitable drips.

As an aside, I was disappointed at how much gunk, rust, and nasty stuff came out of my clutch system. Some Ferrari owners put huge value on a complete past history of dealer service, figuring that the car has experienced perfect maintenance over its lifetime as long as an authorized Ferrari dealer has signed the log book. Sad to say, my car is proof that it’s a lot easier to sign off a “major service” than it is to actually perform it. No surprise, really. Humans are….. well… human and that’s why I do some service items myself.

 

A couple of test drives proved that changing the clutch pump was the right thing to do. Now close maneuvering and backing-and-filling is much better and the shifting is greatly improved, especially the first-to-second gear shift.

My suspicions that the old pump must have had leaking seals is confirmed. The result was a loss of clutch system pressure when holding the clutch pedal down for any length of time, as you might do when easing into a parking place. Sometimes the clutch would bleed down until the car started moving even with the clutch fully depressed. Plus, I think that I got inconstant clutch operation during up and down shifting, depending on how quickly I stabbed the clutch while making the gear change. If the clutch bite point keeps changing, it's hard to make a smooth gear change.

That bite point inconsistency made some of my shifts quite amateurish and it made me think "Damn, is this what it's like when you're too old and nutty to drive a Ferrari? Crappy shifting?" But I'm happy to report that replacing the master cylinder has cured the clutch problems and the car is now much more fun to drive. I feel just as old, but perhaps a little less nutty........... sigh.