"How To" - Clutch Master Cylinder Replacement

[JG SVT]

After watching it weep for a long while, I just replaced the CMC in my '03 SVT 5-door. It was straight forward enough, but for just a couple/few things. Here're some notes.

1. Access to the lower/high-pressure hydraulic line, the one that supplies fluid to the clutch slave cylinder, was particularly tight and difficult, at least I found. Releasing the retaining clip to remove the line, and the getting it back in was a bit of work. To release the retaining clip, I found it easiest to remove the inner fender liner (as per mentioned in this thread; it was easy to remove, though I've seen better designed plastic fasteners), and work in the engine bay and through the inner fender access hole at the same time. (Taking off this inner fender liner also gives an opportunity to remove the remarkable amount of crud that accumulates at the lowest part of the fender and front of the rocker panels, which otherwise just attracts and retains moisture. Plus, freeing up the bolt that affixes the back lower part of the liner to the rocker panel means that that bolt gets touched, cleaned up, and reinstalled with some anti-sieze goop so that it can be removed later, should it need to be.)

2. Bleeding. This was a little interesting. After spending some time, too much time, with the bleeder open/close pedal up/down method, first some fluid came out, then nothing but air. I'd been watching the fluid level from the outside of the reservoir, then the through the fill neck, everything looked okay - the fluid level was still showing to be well above minimum. Still, I wasn't getting the clutch hydraulic lines to fill. What's up with that??

I decided to simply top up the hydraulic fluid reservoir. Immediately, I heard a gurgling, and upon resuming bleeding, fresh clean fluid started to flow right away, and soon nothing but completely airless clean fluid. Done! The clutch actuation/pedal feel was, in fact, better/more positive than it had been in a long time.

The Ford Focus 2003 Workshop Manual does state that there is a partition in the hydraulic fluid reservoir that separates the brake system and clutch fluid reservoirs within the same reservoir bottle (I shoulda paid a bit more attention at the time). It's possible to empty one, and not the other. When the reservoir is filled all the way up, fluid flows over the top of the partition, which fills both reservoirs. I've seen this in a number of other hydraulic reservoirs. So, if you're having trouble getting fluid to flow after a CMC replacement, you might just want to top up the fluid reservoir.

3. The hard plastic parts/ends of the air intake snorkel aren't designed, or so it appears to me, to be removed from the fabric middle part. The plastic parts are barbed and designed to hook into the holes in the weave of the middle part. It looked like separating all this might make it a little easier to remove it from the car for access to the clutch slave cylinder. It would have, but it does come out just fine in one piece.

I didn't remove the MAF sensor, but I did remove its electrical connection, which allowed it to be moved further out of the way.

Barbed fittings, such as the ones dressing wiring to the battery box, suck! Isn't there a better way?

I didn't replace the o-rings on the hyraulic lines.

I did plug the lines with appropriately sized vacuum caps as I pulled them from the CMC, in an attempt to minimize mess and to retain some fluid. This may not have been the best approach. It's hard to avoid fluid loss and a little bit of mess. It may be the best practice to give up on trying to leave fluid in the lines, and just let it all drain into a cup (as was mentioned in this thread) or rag placed in the VERY tight space that's available under the lines. With the lines empty of fluid, you can manoever/finesse the lines into the right place without worring about containing any hydraulic fluid.

It would be nice to get the central junction box (CJB) a little further out of the way to improve access to the hydraulic lines as they enter and exit the CMC, but all the harnessing didn't quite provide the amount flexiblity for me.

I cleaned the little foam breather filter in the airbox. Woo hoo! In fact, pretty much everything else that was removed from the car, and then some as this opportunity provided, also got tidied up.

I have a hypothesis to offer on the life of this part (this doesn't cover mishaps reported here like broken clutch pedal parts, associated damage, and the like). I hadn't ever replaced the hydraulic fluid via bleeding the clutch or brakes in the ownership of the car (I bought it new). I had removed the fluid from the reservoir with a baster, then refilled with clean fluid. The thinking here is that fluid does circulate around hydraulic systems and that this basting procedure might just be enough. After removing the CMC and seeing the black, even gritty, fluid that came out of it, I surmise that a regular bleeding - say, yearly - would have mitigated the failure of this part. Contaminated fluid acts to abrade, and exposes moisture to, cylinder bores, seals and pistons (not that plastic parts care so much about water, I suppose, but metal ones do). It certainly wouldn't have lasted forever, but it may have lasted many more years. Of course, with the divided fluid reservoir, it looks like I wasn't removing very much, if any, clutch system fluid, but only brake system fluid. From this point on, I'm going to do regular bleedings and I'll see how long these bits last.

With cars I've used on the track (road courses and autox), every fluid gets changed before every track event, even if the events are only a weekend apart. I've NEVER had hydraulic system issues EVER on any car that's been serviced this way.

It was probably about 6 hours of work time, not including "staging/prep", clean up, and talking with neighbors .

The car has been very good. This has been the only unscheduled maintenance in my five years and about 60K miles of ownership. Not bad at all. If the next five years goes this way...

Thanks to everyone who contributed to this thread. It has certainly be of great value to me. I hope this additional little bit adds something useful to this already helpful thread.

- JG

[scrammer]

Originally Posted by TeamPrecisionIT

Why is this not stickied?

it was stickied when it was new. how-to's are only stickied for a month or so and then unstickied. there are already too many stickie in the "Ford Focus Technical Chat"

yes, this thread IS located in the How-To Archive

[j-zetec_pr]

i have a dirty left shoe... i'm glad i found this thread. will try to reach Mike for a CMC tomorrow

[stivo]

just did this job. PITA!!!!

I recommend hiring a midget for this one.

[PlasticRacer]

Alright i'm glad i saw this post, but quick question. I've noticed brake fluid on my clutch pedal, but after wipping it off it haven't gotten anything on it again, and just to be sure it isn't dripping, i've placed a paper towel underneath to catch anything so i that i can see for sure if it is dripping and so far nothing. Could it have been something when i was swapping my clutch that caused it to leak at the time???

[shepski]

Sheesh! After reading through this thread, I'm glad my Premium ESP extended warranty is covering it (and the replacement of leaking power steering pump) for only the $50 deductible. 5-plus hours for some people (and probably for me) to do on their own? Yikes!

[SVTdubber]

mine just let out like Niagara Falls today, well its a click over 60K miles so not too bad

pulled the old one out today, waiting for the one from Ford that comes into tomorrow!

[SVTdubber]

just finished putting the new one in, not a bad job at all, worst is putting the clips in, best thing to do as meationed in here is take the fender liner out and have the top open, that way you can tackle it from both places. no more leaky!!

[icebrain]

Originally Posted by pokeySVT

(6). With the bracket loosened I moved back to the engine compartment and unbolted the junction block (where the lines pass through the fire walll), then I removed the clips that hold the hydraulic lines in place.

I have a problem... one of those little clips popped off as I was trying to push it in (securing the bottom hose) and now it's lost. I don't have a replacement for it, either

Is this a common item, or must it be ordered from a dealership?

[stivo]

Originally Posted by icebrain

I have a problem... one of those little clips popped off as I was trying to push it in (securing the bottom hose) and now it's lost. I don't have a replacement for it, either

Is this a common item, or must it be ordered from a dealership?

you'd better get the magnet out and find it. That little clip is special made for that part. I'll guess that you can't get the clip only...

if you really can't find it, then I'd look for one in a salvage yard.