Clutch Master Cylinder gone bad?
10-08-2013, 08:10 AM
#1
Burning Brakes
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Clutch Master Cylinder gone bad?
Hey,
Tried searching the forum for an answer, but didn't have any luck.
My clutch pedal has been sticking at HPDE events and occasionally in traffic in Houston Heat. I was going to just buy a tick MC and replace the sucker, but noticed that the fluid in the reservoir has been crystal clear every day I have checked. So, last night I put some super blue in and expected a combination of blue and clear fluid... Nope straight blue.
I am thinking the master cylinder is not transferring fluid at all. I then decided to pump the clutch with a dry rag sitting over the MC to see if it would shoot fluid into the rag (not sure if it is supposed to - just know it does when bleeding brakes) and the rag was still bone dry.
Thoughts from everyone? Help would be greatly appreciated.
Tried searching the forum for an answer, but didn't have any luck.
My clutch pedal has been sticking at HPDE events and occasionally in traffic in Houston Heat. I was going to just buy a tick MC and replace the sucker, but noticed that the fluid in the reservoir has been crystal clear every day I have checked. So, last night I put some super blue in and expected a combination of blue and clear fluid... Nope straight blue.
I am thinking the master cylinder is not transferring fluid at all. I then decided to pump the clutch with a dry rag sitting over the MC to see if it would shoot fluid into the rag (not sure if it is supposed to - just know it does when bleeding brakes) and the rag was still bone dry.
Thoughts from everyone? Help would be greatly appreciated.
10-08-2013, 08:22 AM
#2
Heel & Toe
Sounds like a bad MC! So you disconnected the line going to the slave, and held a rag over that? If you got no fluid coming out of the line, its def fried.
You could go the cheap and easy route with a factory MC, or drop some cash on the Tick, and spend some time installing it, since it doesnt just twist in like oem.
You could go the cheap and easy route with a factory MC, or drop some cash on the Tick, and spend some time installing it, since it doesnt just twist in like oem.
10-08-2013, 08:31 AM
#3
Burning Brakes
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I haven't disconnected any lines actually. I just assumed with the MC cap off, if I depressed the clutch, fluid would shoot up from the reservoir. Am I incorrect in assuming this?
What method are you recommending?
What method are you recommending?
10-10-2013, 12:11 AM
#5
Heel & Toe
No fluid would shoot out of the reservoir with the cap off. I didn't catch how many miles you have on the car, but for a sticking clutch, the easiest place to start is the MC. In my experience with my 2 C5s, and buddy's C5s as well, swapping for a new MC corrected our sticking pedals. I want to say I paid around $80 for an oem replacement last time I needed one.
As for the tick cylinder, it works great! But really is a pita to install. You have to find some new bends in your fingers!! I wouldn't go that route until you replace the clutch and slave cylinder though. But it's up to you...
As for the tick cylinder, it works great! But really is a pita to install. You have to find some new bends in your fingers!! I wouldn't go that route until you replace the clutch and slave cylinder though. But it's up to you...
10-10-2013, 09:32 AM
#6
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2020 Corvette of the Year Finalist (performance mods)
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fluid will not shoot out of the reservoir with the cap off, the mc cylinder pumps the fluid the opposite way dow the system... mine was the same way, under normal driving I had no problems but under wot the 2-3 shift was very difficult... I installed a tick and it is much better but the 2-3 shift is still a little notchy under wot... I'm thinking the self adjusting pressure plate is part of the problem... I have an act twin disc that will be going on when I decide I actually want to do it
10-10-2013, 06:37 PM
#7
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The problem is heat building up in the diaphragm springs and they sink, as the clutch is starting to wear and plate load ie clamping force is diminished so slipping is induced if the self adjusted pressure plate aren't functioning properly. IMO a new clutch is the only real fix and a master cylinder that moves more fluid to give the slave a longer throw is just a bandaid, it also requires more pedal effort though some people welcome it. Hope this helps, don't hesitate if you have any questions about a Monster.
10-11-2013, 02:31 PM
#8
Heel & Toe
The problem is heat building up in the diaphragm springs and they sink, as the clutch is starting to wear and plate load ie clamping force is diminished so slipping is induced if the self adjusted pressure plate aren't functioning properly. IMO a new clutch is the only real fix and a master cylinder that moves more fluid to give the slave a longer throw is just a bandaid, it also requires more pedal effort though some people welcome it. Hope this helps, don't hesitate if you have any questions about a Monster.
10-13-2013, 02:27 AM
#9
Safety Car
The problem is heat building up in the diaphragm springs and they sink, as the clutch is starting to wear and plate load ie clamping force is diminished so slipping is induced if the self adjusted pressure plate aren't functioning properly. IMO a new clutch is the only real fix and a master cylinder that moves more fluid to give the slave a longer throw is just a bandaid, it also requires more pedal effort though some people welcome it. Hope this helps, don't hesitate if you have any questions about a Monster.
10-13-2013, 12:52 PM
#10
Burning Brakes
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Well I just ordered a new GM clutch master. I decided not to go down the Tick route...
I am hoping this solves it and if not I may need to research the new clutch route.
Thanks for everyone's help so far!
I am hoping this solves it and if not I may need to research the new clutch route.
Thanks for everyone's help so far!
10-13-2013, 06:07 PM
#12
Burning Brakes
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10-14-2013, 05:54 PM
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Not sure what you mean by random? I've contemplated putting a stock clutch back in my car and trying to mount a Go Pro camera underneath with the inspection cover off so I can prove this, but I'm sure it's worth the risk or work...
10-14-2013, 11:13 PM
#15
Safety Car
Some days I can rip gears no problem and other days I can't.
10-15-2013, 12:01 PM
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The self adjusting springs in the pressure plate could be hanging and variying disengagement, see below for in depth explanation...in theory it's a great idea, but doesn't always work in the real world
http://www.schaeffler.com/remotemedi...ech_sac_en.pdf
http://www.schaeffler.com/remotemedi...ech_sac_en.pdf