Any signs to look for if clutch master cylinder is failing?

cop on my back

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I'm talking leaks. I have had nothing but clutch issues with this car and just got a Excedy Mach 500 clutch and racing flywheel installed last week. Clutch is right to the floor to try and get clutch to disengage but it won't at a stop, you can't get it in first.

Took it back to shop and they did a vacuum bleed and it is just the same. New slave cylinder with the kit was installed as well. I am starting to think the master cylinder is leaking some fluid past the seal when you push it so not all fluid is going to slave cylinder.

I'm ready to roll this car off a cliff.

It is a 2015 GT.

 

Tommy V

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These clutches are hard to bleed,the best way to.do it is to keep slowly keep pumping the clutch.pedal.and i mean.alot!!!.It will slowly start to build up pressure.When i.did my exedy clutch it took me about 45 mins to get my clutch pedal to be firm.The first 10 mins i had to.do it by hand and pull the pedal back up.It will bleed all the air out,just takes time and patience.Also make sure your clutch line at the master cylinder is pushed all the way in.
 

Anthony 05 GT

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Agreed^
 
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cop on my back

cop on my back

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Damn, I will just get home after work and pump the shit out of it. I guess I can listen to the radio and have a beer while I do it.
 

Anthony 05 GT

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I recently had the transmission out of my '05 and foot bled the clutch for about 5-10 minutes. The next time I got in it I had the same thing happen as you. After another drive it's fine. I've had that tranny out about 5 times and it's always the same way.
 


stang17

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I've had ongoing issues with 1st/reverse being difficult to engage for the first few miles of driving. Also for the first few miles, if I have the clutch to the floor and have the car in 1st gear, it will coast forward like an auto when your foot is off the brake.

It's an issue with the clutch not engaging/disengaging correctly, most likely due to air in the system as it goes away once there is enough heat in the system.

I've had the stock clutch swapped out for an Exedy Mach 600 with new flywheel, pilot bearing, throwout bearing, slave cylinder, and stainless braided clutch line.

I also went ahead and replaced the shifter with an MGW, added the Steeda reservoir clutch line, and swapped out the trans and diff fluid with BG products.

Transmission and clutch have been out on 2 separate occasions to trouble shoot and system has been vacuum bled at least a half dozen times, slave bench bled twice, even bled the brakes.

Every time we trouble shoot and bleed the system it is good for a few days, then comes back to acting up.

At this point, I'm at a loss of where the air is getting into the system. Brake fluid is clean and filled to the max level.

Slow speeds at slight inclines cause so much clutch shudder the car shakes pretty violently.

My work commute is less than 2 miles, so basically I'm plagued with this issue 90% of my driving time.

8,700 miles on the car.

My dealership says this is a known issue with the mustangs and that the ford service manual says difficulty shifting when cold is normal.

My mechanic has triple checked everything Exedy support has advised, yet no solution as of yet other than to chalk it up as it is what it is.
 
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cop on my back

cop on my back

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Well today it is bad again. Had to turn around and grab the truck to go to work, just couldn't get car in gear when at a stop. I will pump the clutch a million times tonight, but there is obviously an issue that is causing air to get in the line.

Yes, it is connected correctly at the fluid reservoir for those that were going to ask.
 
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cop on my back

cop on my back

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Finally took car to Ford and they confirmed no air in the lines but they don't know what's wrong. I'm thinking master cylinder so I will talk to shop foreman today. I want them to dead head the clutch line and see if the pedal goes rock hard or still depresses, that will definitively prove it.
 
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stang17

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Appreciate the update. Please continue to keep us updated as I'm eagerly looking for a solution myself.
 
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cop on my back

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Ford suspects it is the master cylinder seeing as the slave cylinder is brand new. They wanted $811 to install it....ah let me thing about that. Ordered a Genuine Ford one from my dealer for $91 and will have it on Wednesday. At least my shop is built and I can slowly remove it between now and when it arrives.
 

Nerass

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I experience the same... in for video. I may replace mine also
 

F1scamp

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Take the trans out, if there is nothing obvious, drill an inspection hole in the bellhousing, put it back together and test it so you can physically see what its doing. Once you figure it out and correct it, plug the hole. I've had to do that on 2 cars with weird clutch setups and issues.
 

 
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