Clutch Pressure, Help please.

[Daniel Ryel]

Hello Thread, (This will be TLDR because it has to be for the help I need.)

I am new to the forums but have been looking through them for days not seeming to find anyone with my exact issue. Let me start off by explaining what the cause of my replacement was.

I own a 2011 Ford Mustang GT 5.0 and recently replaced my Clutch Master Cylinder only.

Recently on my way home from lunch and my pedal started losing pressure when shifting from 3rd to 4th gear next time I attempted to shift the pedal dropped to the floor.

I was unable to get it into gear without rpm revving until it allows gear shifting to get a half mile home.

I started looking up what it could be, however I noticed I smelled brake fluid in the car now.

After looking and not seeing a leak right away I took to the forums and online videos, seemed pretty clear that the clutch master cylinder may be the issue.

Got the manual out and started wrenching. Found after a minute of wrenching that break fluid was coming from the clutch master cylinder. Strapped up cleaning supplies to start saving my paint and carpet from the devil aka dot3.

Moving forward got the replacement from AutoZone.(I know but time was a concern the first day of working on it before you say it.)

Reinstalled per the book. and started the bleeding process which seemed unclear until looking up a few youtube videos.

The process I repeated many times over goes as follows.

With the new master cylinder installed, I then purchased a rubber stop plug. drilled into it to create a plug that would create vacuum when Appling a bleeder Vac to it.

I then made sure the fluid level is at max and brought the driver side up 8 - 12 inches, then inserted the plug and tested to make sure there were no leaks in my rubber plug I get 0 pressure loss. Plugged the master and brake cylinder reservoir and created 20 inches of pull or pressure seen it worded both ways. held for 1 minute released rapid pressure and got in the mustang to pump the clutch 10-12 times each time and repeated the steps three times in total.

Starting out I had to pull the pedal back each time the second time the pedal started to fall back on its own when released just very slowly and sometimes required me to manually pull the clutch pedal back with my foot then third go It was pretty much the same but went back on its own each time with no intervention, however was still way to soft and would not allow me to switch into gear at all using the clutch. Last 3/4 of travel I pretty much feel no pressure at all but the spring allows it to go back to its normal position.

From here I was confused as to what the issue was so I repeated the process and even disassembled and reassembled the whole pedal and clutch master cylinder assembly for inspection. Everything appears fine.

Reading online and watching videos you see everyone and there mom saying haha you are just *insert snarky comment here* keep pushing that pedal 1-250 times and it will eventually get harder and where you need in order to get into gear.

This does not happen though, I even tried parking on an incline hill for over 30 minutes by my house pumping the whole time well over 500 times. Based on finding videos explaining that I have a bubble in the line trapped in a location that needs to be tilted to be released.

Nothing is working people.

I am not an expert by any means, but have bled many brakes not clutches in the past and I have people with more experience then me with clutch systems scratching there heads.

I know the next logical place to go for me in my head is dropping the transmission and getting dirty with the slave, but keep in mind, since the first time I filled the fluid to max the level has not dropped so I don't see how there would be a leak with 0 fluid loss, so I feel like there is something else I am missing the mark on entirely.

Please someone who knows what they are doing shed some light on my situation on what may be going on. Been at it for three days now, ordered another clutch master cylinder from Ford directly in town and it will be here tomorrow in case of a defect in the one I purchased from AZ.

 

[SilBult]

I've never had to bleed the clutch on my '14 GT so I am not positive this will work, but after all you've done so far it should be worth trying. It seems unlikely to me that you have air in the slave cylinder. You will need an assistant to do this. I would disconnect the clutch line at the transmission and place the end of it in a container of clean brake fluid and then have someone operate the clutch. When the clutch is depressed air should come out of the end of the clutch line. Since it's submerged in brake fluid no air will be able to re enter the line. Hopefully if this is done several times all the air should be expelled and you can re connect the line to the transmission and with a few more strokes of the clutch pedal you should be good to go. Good luck.

 

[jlmotox]

I just manual swapped my car and all I did was connect all the hoses, master cylinder, throw out bearing and pumped the clutch pedal till my leg was tired (100ish pumps) and all the air worked it’s way out... 06’ GT...

 

[Daniel Ryel]

Thanks, unfortunately mine will not do that currently. JLMOTOX.

SilBult, I think that I will try that as it does makes since in theory.

 

[rocky61201]

When the throw out bearing goes bad or pops, the end result is a seal going bad and fluid leaking out and all over the ground, kind of like a harbor freight jack. Since that is not happening because you have no leaks and it appears you have bled it properly I have to ask, what color is your brake fluid in the reservoir and how old do you think it is? Old and dirty fluid will yield poor pressure especially when it heats up by cooking your brakes on a hard stop.

If you suspect it is old and dirty it will do no harm to flush the whole system with new fluid.

Or you could install a separate plastic clutch fluid reservoir right next to the brake master cylinder and cap off the port not being used anymore on the brake master cylinder. Road racers usually do this because they are on the brakes all the time and heat up the fluid pretty good.

 

[Daniel Ryel]

Rocky61201, I didn't realize that they made a add on reservoir

When the throw out bearing goes bad or pops, the end result is a seal going bad and fluid leaking out and all over the ground, kind of like a harbor freight jack. Since that is not happening because you have no leaks and it appears you have bled it properly I have to ask, what color is your brake fluid in the reservoir and how old do you think it is? Old and dirty fluid will yield poor pressure especially when it heats up by cooking your brakes on a hard stop.

If you suspect it is old and dirty it will do no harm to flush the whole system with new fluid.

Or you could install a separate plastic clutch fluid reservoir right next to the brake master cylinder and cap off the port not being used anymore on the brake master cylinder. Road racers usually do this because they are on the brakes all the time and heat up the fluid pretty good.

like that it sounds neat and I might look into that for sure in the future, regarding the brake fluid, it had been changed recently, however we did keep an eye on the integrity of the fluid as much as the human eye can and it looks good to me and not like what I've seen in some cases in the past, however regardless of this, I believe that two of you have recommended flushing the fluid fully and I believe that would probably be a good idea for when I get the new Clutch master cylinder tomorrow. I will give that a shot and see what happens from there. Any other advice is always welcome you guys have given me a few new options to try out at this point and I thank you for that so far.

 

[Daniel Ryel]

When the throw out bearing goes bad or pops, the end result is a seal going bad and fluid leaking out and all over the ground, kind of like a harbor freight jack. Since that is not happening because you have no leaks and it appears you have bled it properly I have to ask, what color is your brake fluid in the reservoir and how old do you think it is? Old and dirty fluid will yield poor pressure especially when it heats up by cooking your brakes on a hard stop.

If you suspect it is old and dirty it will do no harm to flush the whole system with new fluid.

Or you could install a separate plastic clutch fluid reservoir right next to the brake master cylinder and cap off the port not being used anymore on the brake master cylinder. Road racers usually do this because they are on the brakes all the time and heat up the fluid pretty good.

Also, I was really hoping it wasn't or isn't the slave cylinder/throwout bearing as I guess from what I read its a combo( I may be wrong but maybe at least both in the bell housing, anyways I figured it would be leaking all over the ground, but wasn't sure due to it being in the bell housing, however as stated about I have no fluid loss on the ground or reservoir besides the small spills from me getting frustrated at times and becoming impatient.

 

[rocky61201]

Also, I was really hoping it wasn't or isn't the slave cylinder/throwout bearing as I guess from what I read its a combo( I may be wrong but maybe at least both in the bell housing, anyways I figured it would be leaking all over the ground, but wasn't sure due to it being in the bell housing, however as stated about I have no fluid loss on the ground or reservoir besides the small spills from me getting frustrated at times and becoming impatient.

The separate clutch fluid reservoir is a simple clear plastic deal and kind of generic. My son's 97 Ranger has one. IIRC my old 92 Toyota had a separate reservoir as well. Lots of cars have that setup from the factory. Nothing special.

I got a 2006 so I have the TR3650 and it has a small view hole at the bottom of the bellhousing. First ToB I blew and it all leaked out there. Even drained the master cylinder reservoir. I'm not sure if there is a similar hole in the bottom of the MT82.

I don't have the picture anymore of what I did in the past so I'll try my best to explain it. The pic might still be in a post of mine a couple years ago. I hooked up the master cylinder with the clutch line and attached a piece of clear tubing to the feed port of the master cylinder and a small funnel to pour the brake fluid in the clear tubing. Then I hung the whole assembly up so it was vertical with a piece of string. When everything is straight up and down with no bends in the lines it makes it easier to work the air bubbles out. Poured the fluid in the funnel, the pumped the master cylinder by hand and watched the fluid and bubbles come out the bottom of the braided clutch line into a tupperware dish. Once I was satisfied I capped both ends with vacuum tube caps and installed back in the car.

 

[Juice]

Since nobody asked: How many miles on this clutch?

 

[Daniel Ryel]

Alright guys replaced the slave cylinder and the clutch issue is gone, now I have another issue. I'll be posting shortly. Unrelated to the transmission.

 

[Juice]

Alright guys replaced the slave cylinder and the clutch issue is gone, now I have another issue. I'll be posting shortly. Unrelated to the transmission.

You pulled the trans to replace the slave cylinder and did not replace the clutch?

 

[Daniel Ryel]

@Juice No never pulled the trans and did replace the clutch with a full kit. Only replaced the master cylinder before that.

 

[crjackson]

@Juice No never pulled the trans and did replace the clutch with a full kit. Only replaced the master cylinder before that.

I must be having a senior moment. It sounds like you somehow managed to replace the clutch/tob without removing the transmission.

So I have to ask … Did Samantha Stevens twitch her nose to get it in there?