Playing the parts game to solve the clutch problems.

[PunkST]

Anything is possible.

 

[MagnetiseST]

https://www.fiestastforum.com/threads/clutch-issue-recently.19956/post-344257
The point is, the issue could be related to a hydraulic system that isn't quite sealing.

Unlikely. The fluid should never get low enough to induce air into the system, if it does, there is a leak. Also if the fluid gets that low, you'd likely have a brake system issue too.The fluid runs from the brake master, through a plastic line, to the clutch master, through a hard line, to a soft line, to a hard line, to the slave. There is one bleeder on the system and all of the line connections are made through push lock connections (not flared lines). The only places it could leak would be the slave, the master (seals), or the line connections. Two of those three would be externally visible, once the slave leaks enough it drips out of the bellhousing as well.

 

[Intuit]

Unlikely. if the fluid gets that low, you'd likely have a brake system issue too.

Quote from manual...



The FULL quote...

<<https://www.fiestastforum.com/threads/clutch-issue-recently.19956/post-344257​

<<First thing you'll want to do is check the fluid level for the clutch hydraulics. The fluid reservoir is somewhat shared by the brake hydraulics. For safety, that reservoir is compartmentalized. Shine a STRONG light on that reservoir and check to see whether the fluid, on the clutch side, is low or drained. The clutch master cylinder can leak internally or externally. The slave cylinder can only leak externally. So depending on whether you're losing any fluid, you can get an idea on where you might be able to first cast your scrutinous eye. >>​

​

Has anyone checked to see whether or not you can drain the clutch fluid without triggering the brake fluid light? Prior car never would turn on a light for low clutch fluid. If the fluid got low, small amounts of air would be introduced into the system, resulting with a "slow fail" situation. (had a leaky clutch master cylinder)​

​

Had a hellova time keeping the motorcycle brake bled. The brake lever would slowly transition from hard to mushy. Longer story short, it was sucking in tiny amounts of air, with each release of the brake lever. (air is less dense than fluid) The amount of fluid loss was only detectable by blowing off the bleed screw with 150 PSI exiting an air gun. (so *really* tiny amounts of fluid) Had to grind down the bleed screw seat.​

​

The point is, the issue could be related to a hydraulic system that isn't quite sealing.​

​

 

[MagnetiseST]

Interesting, I didn't know they were compartmentalized inside the master reservoir.

I still don't think reducing underhood temps will solve anything related to slave failure though.

 

[Intuit]

Interesting, I didn't know they were compartmentalized inside the master reservoir.

Yeah it's a safety thing; it's just a spillway. That's why it shocked me when you stated it wasn't setup that way. (in disbelief, literally had to reread it - then deleted my post until I had time to confirm it) Found that out the hard way while bleeding the clutch on my prior vehicle. It was near impossible to read the fluid level on the clutch portion of the brake reservoir... which represented just a tiny *back* corner of it. So the brake would read at the low mark, while the clutch could be bone dry. So I'm bleeding it while trying to maintain the fluid at or above the "low" mark on the reservoir... never realizing that it would *never* go below the low mark. By the time I'd add, it would've already drained the clutch reservoir, introducing new air. Never discovered that fact until I got tired of adding. Eventually the clutch system ran dry. That was a frustrating hour+ that I wanted back.

I'll post bleeding instructions from the manual. (if someone hasn't done it already) Haven't really absorbed it, but there seems to be quite a lot of steps for what is typically a very simple process.

I still don't think reducing underhood temps will solve anything related to slave failure though.

I hadn't made that point but think I would've agreed with you. But interestingly, something else in the manual caught my eye after posting last night; particularly the function of, and interaction between release bearing and slave cylinder.






What happens if this integrated, always rotating, release bearing, is bad? It gets pretty damned hot. (this can happen without it squealing or locking up) What happens when it's constantly hot? Extreme heat ain't good for the spring, seals . Given the description of its operation, there a few different possibilities that (theoretically) could result with the clutch pedal being stuck on the floor.
* Boiling/vaporizing the fluid in the slave cylinder
* Piston binding
* Seal leaking pressure

Some or all of these could theoretically occur. Re seal leaking pressure, that could only be the case if the pedal is stuck the floor *while* the engine/trans still have some engagement. (so it's stuck to the floor but you can still slip and/or accelerate)

Agree? Disagree? Partly agree? Additional considerations?

BTW, with any and every clutch I've owned, I've always held them in at traffic lights. So far not an issue out of any of them. Only part needed to replace thus far is a leaky master cylinder on the firewall of the previous car.

 

[PunkST]

^ i used to always hold mine till it has started acting up. But my issue is so intermittent. It could have been from the first deer i hit, could have overcooked it on a 90 degree day driving to my parents place ( though i think a 3 hour drive at 70 ish miles an hour wouldnt overheat it considering im hardly even using any power or creating more heat than normal)
Its come back up ( the pedal) every time. Pretty violently too, almost like something got stuck. And i can go for weeks or months before it re occurs. Or it could be once a day..

 

[Intuit]

Questions:
0) Has the system been bled yet?
1) Using "DOT 4 LV" fluid? "LV" designation means low viscosity. (don't know whether it makes a difference but repair shops probably won't carry it and will use regular DOT 4)
2) Is there any lingering engagement between engine/trans while the pedal is stuck to floor?
3) Fluid level in reservoir been consistent? If not, any wet spots on the firewall beneath the push rod?
4) Re deer strike, was there anything unusual about clutch operation during the event? Was the engine stalled?
5) Feel anything unusual about resistance when pushing the pedal, or if possible, the push-rod (behind the pedal,) by hand? (engine off of course)
6) Some part of the clutch hydraulic tube between the master cylinder and engine, should be flexible. But if (somehow) it's all hard line, are the engine mounts all intact/healthy?

With the added changes and complexities of this system, basically we need to devise some way of isolating/testing/eliminating individual components. There's just too many possibilities. The clutch springs are supposed to provide the return force. I've heard of clutch springs breaking on other vehicles, but never heard of them binding. On ours, they've built some sort of adjustment mechanism into the actual clutch assembly and I won't understand how it works, without putting my hands on one. (visit a parts store with one in stock that you can open for inspection) Even the master cylinder is significantly different from my prior vehicle; there's no way to make clutch pedal engage height adjustments. The manual (kind of) claims this is unnecessary because the master cylinder is able to return fluid to the reservoir.

If I *had* to guess, my best guess would be the slave/release bearing. But one has to take the transmission off to get to them anyway... in which case and not being sure, just do the whole kit & kaboodle. But if money were the issue and all the labor is my own, that's where I'd rest my bets. (depending on how the above questions are answered of course)

 

[PunkST]

Has not been bled yet.
Using correct fluid.
Fluid level has not dropped since i added some to see if it was part of the issue
Yup went from 60 mph in gear to skidding stalling stop. I didnt have time to hit the clutch pedal as the deer was already on my car.
i can test the resistance tonight.
There is a little bit of engagement. At least enough that the pedal pops back up loudly sometimes.
My mounts should still be ok. Highest milage is upper trans with 126k, then rmm with 90k and pssm with 58k. Lower milage units are poly.

If im honest the pedal feels like my old clutchmasters stage 3 in my svtf. Kinda heavy. But not awful. Then again i learned stick on a truck..... Lol

 

[MagnetiseST]

I hadn't made that point but think I would've agreed with you. But interestingly, something else in the manual caught my eye after posting last night; particularly the function of, and interaction between release bearing and slave cylinder.


What happens if this integrated, always rotating, release bearing, is bad? It gets pretty damned hot. (this can happen without it squealing or locking up) What happens when it's constantly hot? Extreme heat ain't good for the spring, seals . Given the description of its operation, there a few different possibilities that (theoretically) could result with the clutch pedal being stuck on the floor.
* Boiling/vaporizing the fluid in the slave cylinder
* Piston binding
* Seal leaking pressure

Some or all of these could theoretically occur. Re seal leaking pressure, that could only be the case if the pedal is stuck the floor *while* the engine/trans still have some engagement. (so it's stuck to the floor but you can still slip and/or accelerate)

Agree? Disagree? Partly agree? Additional considerations?

BTW, with any and every clutch I've owned, I've always held them in at traffic lights. So far not an issue out of any of them. Only part needed to replace thus far is a leaky master cylinder on the firewall of the previous car.

Huh I never read those pages in the shop manual, or couldn't find them. Interesting.

I can't relate on the holding the clutch down at the light, I have never ever done that in any of my manual cars. But yes that would cause excess wear on the bearing and heat everything up. However cooling the fluid itself wouldn't help, not without a way to pump it through the system.

I wonder if the majority of people with this issue do hold the clutch down at lights... None of the people in my household do this, and none of our fiestas ever had this issue.

 

[PunkST]

^ ive always done so on all my other cars, unless sitting for over a minute. Imo doing that shouldn't even come close to ruining a part. Even on a hot day. Even the way too strong for the car aftermarket set up in my old focus never had an issue unless i got caught in a traffic jam. Then and only then would the pedal start to get a bit spongy. But that was also dot3 fluid. Never once stuck to the floor like this car has 🤷

 

[MagnetiseST]

Well Ford's been using internal release bearings for some time in the Focus it seems, but just because the old one can handle it doesn't mean the FiST one is identical and capable of the same things. I don't think there is a definite answer for this problem, I truly think the parts are hit and miss. Remember the FoST uses a very similar part and I don't see this issue happening in their community, I also don't think that they replace the slaves when they do a clutch or drop the transmission lol.

 

[RubberDucky_82]

Jumping in to say that, yeah, I was holding my clutch down at lights and when stopped in traffic. Ever since the dealer replaced my slave cylinder and throwout bearing at 30k (and still being a manual transmission noob) I was wondering if holding it down was causing some sort of excessive wear. I've since been doing it less. I'm glad you mentioned this, @MagnetiseST, and I'm curious if you're on to something.

 

[PunkST]

So ford cheaped out somewhere and expects us to foot the bill for major repairs every time it goes out due to a bad design. And with no actual higher quality part to replace it with, we are essentially rolling the dice every time we drive a relatively new car hoping we dont get stranded. Thats unbelievably shitty. No wonder folks have been trying to sell these cars off left and right. Ford's quality has dropped majorly.

 

[MagnetiseST]

You are certainly entitled to your opinion, and yes its a $30 part. However I wouldn't call it "cheap" or that Ford "cheaped out", it is a cost effective part with an inherently good design that has a seemingly high failure rate on the internet. However the people with these clutch slave problems at >50k miles tend to be the minority group, and within 60k miles it CAN be covered under powertrain warranty depending on how good of a relationship you have with your service department. If you bought any type of extended powertrain warranty or vehicle coverage it MIGHT be included as a warrantable part. We just traded in one of our FiSTs, 91k miles, two clutches, and two transmission replacements. Three times the slave was replaced, but not because it failed, just as a precaution since the transmission was down. None ever showed any signs of leaks, and the first one was in there until 50k miles. I feel like the output shaft bearings are more likely to fail then the clutch slave, seeing as that's what killed both of the transmissions that we removed. I wouldn't say you are rolling the dice either, if you have symptoms and choose to continue to operate the vehicle then yes, but that is a choice you make. Ford didn't force you to drive the car.

Ultimately it takes about 2 hours to drop the transmission in your driveway, its not the easiest job but its certainly do-able. After that its 2 8mm bolts and the slave it out. Its more annoying to get it back into the car then it is to take out, I suppose its the most common thing I've done in the last two years on these cars though lol

 

[PunkST]

^ i must be spoiled then thinking that i shouldnt have to break my back in a driveway every 40k miles to replace a part that could have been designed properly for a long service life. ( with my back issues its getting harder and harder to do the work. And local 3rd party shops arent exactly trustworthy) Hell they could have designed the transmission to take the focus ST slave cylinder to save them money in part design but assumed it would be ok. The lack of service department doesnt do anything to help customers out at the local dealers here. So thats out for an option.

I purchased it thinking it would be as reliable as my last ford. Clearly i was an idiot to do so.

 

[Ford ST]

You have over a hundred thousand miles on your car and you haven't dropped the transmission once what are you complaining about.

I know you like Volkswagen. Well I've seen a hell of a lot more Volkswagens with problems than this car.

Is it perfect no.


Sent from my LG-LS997 using Tapatalk

 

[PunkST]

^ i havent dropped it because i do NOT have the time to have a car down. I also just got done with that song and dance last year with wifes car. I dont have the strength or folks to call on for help either.
Having to pay the rediculous amount shops want to replace a 40 dollar part. ( which they'll probably mess the damn car up more) isnt very feasible at the moment. Due to time and money once again.

I really wish there were an updated part that i could be absolutely sure the problem would be 100% solved and not come back. I dont have the expendable time and income to be doing this every 3 years. Im frankly shocked ive even gotten 100k out of this car.

Now maybe stop trying to gaslight me or forcing me to again re explain my situation.

 

[Intuit]

Yeah from a few experiences with less than half-a-dozen visits over my lifetime, I don't frig'n trust the shops either. Neither should holding the clutch in at lights be especially different with this vehicle versus others.

I put well over 300k trouble free miles on my last man trans before the car rusted out (>60k so far on the motorcycle) and expect to do the same here. It's why I only buy man trans. Note, that I've taken to ignoring the clack on clutch release; believed to be slop in the input shaft.

 

[PunkST]

Im gonna be crawling under the dash to take a really close look at the master and pedal.

 

[MagnetiseST]

Im gonna be crawling under the dash to take a really close look at the master and pedal.

I tried this, there is a very thick piece of foam / insulation that seems as though it would absorb the fluid should it leak into the cabin. I couldn't see shit.

And tbh if you have over 100k on your car, and its JUST starting to give you trouble, I don't understand what the complaint is. It is considered a "wear" item and it would be considered extreme wear if you were holding in the clutch every time at lights. The slave is not meant to last the life of the vehicle, just as the clutch itself is not meant to. Even my release bearings in my old Hondas wore out, still had to drop the transmission to change those. Just because Ford integrated it as part of the slave cylinder doesn't mean its any more or less useful or a poor design. Concentric slave cylinders were exclusive to racing for a long while before they became used in mainstream automotive designs. Clutch release bearings and bearing forks connected to the clutch slave were the norm, and its just as annoying to keep replacing an external slave as it is the internal. I'd rather have the internal that I replace every 100k miles vs an external that fails whenever it feels like it.