• Sign Up! To view all forums and unlock additional cool features

    Welcome to the #1 Fiesta ST Forum and Fiesta ST community dedicated to Fiesta ST owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the Fiesta ST Forum today!


Clutch mooshy since axle replacement

Clint Beastwood

2000 Post Club
Messages
2,591
Likes
2,338
Location
Laguna beach
#1
Anyone know if they have to mess with brake fluid during an axle replacement? The clutch is real soft now and it engages way down at the bottom of its travel. 17k miles. Fluid was fine but i topped it off. Brakes feel great.
 


OP
Clint Beastwood

Clint Beastwood

2000 Post Club
Messages
2,591
Likes
2,338
Location
Laguna beach
Thread Starter #5
I'm not sure how or why this would have been caused by replacing an axle unless whomever performed the replacement is a 400lb Gorilla named Mungo, but since you DO have a mushy clutch pedal I'd recommend that you bleed your slave cylinder. It's very easy to do. I bled mine when I replaced my slave cylinder during my LSD install.

Remove the airbox and search around under the foam-wrapped wire harness here:
View attachment 20445

Then pop off this yellow cap and attach the line from your gravity bleeder or vacuum bleeder, and twist the valve open:
View attachment 20446

Make sure your brake fluid reservoir is topped off and give the clutch about five pumps, holding it for a few seconds each time. While bleeding the clutch pedal will bottom out easily and you may need to pull it up manually - this is normal. Confirm that there is ONLY fluid in the line attached to the bleeder valve. Twist the valve closed, remove the bleeder line, and replace the cap. Your clutch should now be nice and firm.

If this doesn't solve your issue, my best guess is that Mungo busted something. That boy doesn't know his own strength.
Thanks for the quick write up - it feels less spongey but it still seems like the throw is really close to the floor, engagement point is roughly 1/3 off the floor. Not having a threaded adjustment rod sucks :|

I bastardized my engine oil extractor pump with aquarium tubing to do it :p I ran 5 feet of hose so I could see from the driver's seat and video chatted myself from iphone to ipad so I could see the level inside the reservoir in real time :p

I'll put some miles on tomorrow and see how it feels.
 


Sekred

1000 Post Club
Messages
1,395
Likes
401
Location
Mid North Coast
#6
For anyone that is interested in the correct procedure to bleed concentric slave cylinders.

TECHICAL SERVICE BULLETIN
TSB-CSC0
1

Bleeding Concentric Slave Cylinders


When fitting a new Concentric Slave Cylinder (CSC) it is important NOT to pressure bleed the hydraulic clutch system. This can over pressurize the concentric slave cylinder & cause the cylinder to fail.


Please follow the manual bleeding procedure below.

Open the bleeder. 
Depress the clutch slowly. 
Keep clutch pedal depressed (Do NOT Release).
Close bleeder valve. 
Slowly release clutch pedal.

The manual bleeding procedure must be completed 20 to 25 times
 


Last edited:

Sekred

1000 Post Club
Messages
1,395
Likes
401
Location
Mid North Coast
#7
I found that service bulletin on a clutch manufactures website. The Ford method looks like a reverse pressure bleed. I have seen that method recommended for concentric slave cylinders before as well as vacuum bleeding.
 


OP
Clint Beastwood

Clint Beastwood

2000 Post Club
Messages
2,591
Likes
2,338
Location
Laguna beach
Thread Starter #8
Krug - thanks for the original reply, clutch feels a lot better. I hadn't realized how bad it was, i was tip-toeing the clutch pedal completely to the floor and still the shifter occasionally felt notchy. Now it's engaging about 50% of the way through the throw. There's some residual mushiness.

I put in DOT4 because thats what the master cylinder cap said, but in the manual it says DOT4 LV - do I need to worry?

Also, you should start a new thread called "clutch bleed procedure" for posterity's sake - I searched high and low and couldn't find the procedure here on the forum. Perhaps I was wording it incorrectly, but it totally seems sticky-worthy.
 


OP
Clint Beastwood

Clint Beastwood

2000 Post Club
Messages
2,591
Likes
2,338
Location
Laguna beach
Thread Starter #9
No problem, man, glad it's better. You may need to bleed it again to get it back to where it should be, there could be residual air in there somewhere. Bleeding the slave cylinder is literally the only "adjustment" for the clutch that our cars feature.

I still have zero clue how an axle replacement would have caused this outside of some serious ham-handedness knocking something that shouldn't have been knocked. As long as your lines aren't damaged or leaking, I'd guess that you're fine.

As for the fluid, no, don't worry about it as long as it's decent DOT-4 you're fine. DOT-4 LV is just "Low Viscosity" but pretty much all DOT-4 fluids are compatible and shouldn't cause issue. I used Valvoline DOT-4 fluid when I replaced and bled my slave cylinder. I'm pretty sure it was not specifically "LV" but I have not had a single issue since the procedure.
It was fine after the first axle replacement, but I had to take it back because it was puking oil out through the new seals. When I went back in to have the seals replaced they did it in like 2 hours while I waited - afterwards is when I noticed it was mushy. It could be that it was already mushy and I had just been slowly adapting to it, then the rework appointment made me extra sensitive.
 


OP
Clint Beastwood

Clint Beastwood

2000 Post Club
Messages
2,591
Likes
2,338
Location
Laguna beach
Thread Starter #10
Ok so I did a clutch bleed, ran an entire bottle of fluid through. I still feel like I have to push the clutch down a lot further than I used to when the car was new to get it into first gear and from first to second, but the other gears seem ok with less clutch travel.

This *might* be a sensory thing because I recently made some headway on a neurological injury that has been with me for a while, so lots of things "feel" different as I get sensation back in my extremities, but I still feel like I have to put the clutch pedal to the floor to get into gear in 1st.
 


OP
Clint Beastwood

Clint Beastwood

2000 Post Club
Messages
2,591
Likes
2,338
Location
Laguna beach
Thread Starter #12
Glad to hear that nothing is broken. On the car, anyways. Even if the clutch bleed wasn't necessary, now you know how to do it!
Yeah its a lot easier than most cars I'd owned. I still kinda feel like having to put the clutch almost to the floor to get it into first is not the way it used to be, but I could be wrong.
 


OP
Clint Beastwood

Clint Beastwood

2000 Post Club
Messages
2,591
Likes
2,338
Location
Laguna beach
Thread Starter #13
RESOLVED! I wasn't crazy, BUT the clutch was totally fine.

The issue was: (drumroll) the seat slider bracket was loose on one side, so when I pushed the clutch my seat twisted just far enough that at full leg extension it wasn't fully disengaging. The culprit was a tiny rock, after removing the tiny rock from the seat track it firmly engages on both sides, and now that it doesn't twist when I use the clutch I really notice it. The "variable engagement point" I was feeling is totally resolved.
 


OP
Clint Beastwood

Clint Beastwood

2000 Post Club
Messages
2,591
Likes
2,338
Location
Laguna beach
Thread Starter #14
I think at the beginning I did have air in there because the bleed helped a bit, but the seat twisting by just a teensy bit was enough to throw me off. I thought the seat squeaking was just a FiST noise to be tolerated lol. No more squeak, no more twist.
 


Similar threads



Top