REDHOTS

Now what? Clutch was dealer replaced 1 year ago, and 600 miles. The last 100 miles, or so the clutch pedal seems light on the return stroke. Then yesterday, it stayed on the floor for a second, before starting the car. It had a new flywheel, plate, disc, bearing, slave, and master. Pretty much all of it. Have changed the reservoir fluid twice already. I think the dealer will stand behind it, just need some ideas to convince them.

73Corvette

Everything stock? Did you use the Ranger Method when changing your fluid?

https://www.corvetteforum.com/forums...the-floor.html

http://www.rangeracceleration.com/Clutch_Care.html

REDHOTS

Yes, everything is new GM, only 600mi, and doing the Ranger, although I do not think it is a dirty fluid problem.

73Corvette

May not be... you might have a master cylinder issue...
Does it do it under normal operation or mostly at higher RPM's?

When I said master cylinder issue... I mean AIR

https://www.corvetteforum.com/forums...-cylinder.html

https://www.corvetteforum.com/forums...-cylinder.html

REDHOTS

Did it with the engine off. If there was air in the system, disengagement would be the issue, I would think.

73Corvette

REDHOTS

Seem to have plenty of dis-engagement travel. Pressure plate adjustment going over center? That is the only adjustment in the shop manual, but it does not say exactly, what the adjustment is for? Or TO bearing dragging?

73Corvette

Well.... doesn't look like we're getting much help here...
This weekend there will be some guys that will pitch in... that are way smarter than I am...

REDHOTS

My 81 Camaro ( built from a 400ft pile of steel tubing) has a $150 Howe hydraulic TO bearing, 7/8ths Howe master, and Wilwood pedal on a stock clutch. It is absolutely the smoothest clutch operation I've ever had. The C5, not so much.

73Corvette

Our 07 FJ Cruiser is a 6 speed and is supercharged... A LOT of FJ's Throw out bearings went south in the first 20k miles...and when it went it galled the bearing to the quill and takes out the transmission.... We have over 100k on our FJ that we bought new in 07 and it's still good... I am pretty easy on clutches... I hope that the same finesse with the C5 clutch will make it last as well... I've been driving standards in the oil field for 30 years....

73Corvette

LonestarFRC? Bill Curlee? Lionelhutz? 4drush? Sig?

LoneStarFRC

Several years ago I had this exact same issue. I tried a variety of things (including the "drill-out-the-restrictor-orifice-and-rebraze-the-hard-line" mod done by Shirl "MrEracer" Dickey) and NOTHING worked.
I installed a TICK master cylinder and have not had one single problem since. That was at approx. 5, maybe 6 years ago.

Btw, yes I knew there would be some increase in pedal pressure, but I was prepared to accept it if it solved the problem. There was, and it did.

My guesstimate would be about a 20-25% increase in pedal force. I'm so accustomed to it now I don't even notice it anymore.

73Corvette

Sounds like a master cylinder issue...

OUCH!
http://www.tickperformance.com/tick-...rvette-c5-z06/

73Corvette

THANK YOU!

Sounds like a master cylinder issue...

OUCH!
http://www.tickperformance.com/tick-...rvette-c5-z06/

k24556

All you need is a stock master. However, usually when they go, they often bypass fluid back to the reservoir and you never see a fluid leak. The usual condition of a bad MC is incomplete disengagement of the clutch.

Now, the MC is balanced for fluid capacity with the slave, so you get the correct volume of fluid to move the slave the correct distance to properly disengage the clutch, when the clutch pedal is to the floor. If you overmatch MC to slave, you can blow the MC seal. Another thing that will blow the MC seal is operating the MC with the QD coupler disconnected. Then you are deadheading the MC (ask me how I know, you gotta get that coupler together RIGHT). Drilling the orifice in the MC can also possibly cause this.

Inside the bellows of the slave is a light spring that keeps the T-O bearing just against the PP fingers, That way, the clutch system self-adjusts to make sure pedal travel perfectly matches the need to disengage at full pedal depression. that's why you never have to adjust pedal free-travel.

Clutch dust is very fine and it goes past the slave seal and gums up the fluid. That's why the fluid gets so dark. Now there isn't any return so the gookiest fluid stays in the slave. This will cause the pedal to stick to the floor, just like air in the system.

Your driving habits, or the driving conditions (heavy stop and go) can lead to a lot of clutch dusting. Also a new disc has to seat in just a bit. That means making lots of dust.

This might explain why it worked for a while after swap and now is not.

Therefore a new master at this point is throwing parts at the problem. You need to do a proper bleed of the system, which means either a remote bleeder or really small hands. Ya gotta get the air and gunk out of the slave. The Ranger method is a great maintenance action, but not so effective on air or deep gunk.


Then, after a thorough bleed, if it still is not working correctly, your only hope is tossing parts at it. In parts-toss mode, the MC is the easiest and therefore first in this game. Next is slave, and if you go that far, by all means put a remote bleeder in.

Tick has a great package, and forget all the BS about the copper washer. I've installed several of their remotes and NO problems whatsoever. (this is not a testimonial, I've bought them from Monster Clutch and they are basically the same)

If you are going back to the dealer, I would certainly have my warranty papers in hand and give it a go. If it is a bad slave, then looks like he is on the hook for replacement. If he goes that far, I suggest firm but kind words and a $50 wrapped around a remote bleeder kit, and a walk back to discreetly talk to the mechanic.

dork

What does it mean, "your are deadheading"?

I've got about 3,000 miles on a new Tick MC. When I finished mounting it and connecting the pedal, I filled it with fluid and pumped the clutch pedal once to see the fluid flow from the QD 'just to make sure it worked'. When it did, I connected the QD. Did I damage the MC?

Thank you.

LoneStarFRC

Wow, so I guess I should promptly remove my Tick MC and reinstall a new GM MC. Gotcha!

REDHOTS

Great info k24556! Thanks. I am starting to understand, what maybe the problem. From the way it feels, with engine off, sitting overnight, first few quick strokes, slight pop coming back up from the bottom, then it frees up and seems ok. Seems like the TO bearing is hanging up at full stroke. If it continues, or gets worse, will pull a couple pipes, and the inspection cover and check it out. Will bleed the slave, and lube TO bearing sleeve if possible.

k24556

you don't want to put any lube in there. The clutch dust will gum it up. everything that slides has clearances to run dry. The slight pop is normal if the pedal sticks. Not sure what causes it, but when I bleed mine the pedal sticks and when you lift it up it will pop

REDHOTS

Just wondering, could it be as simple as weak pedal assist/return springs, and dry pedal pivot after 18 years/72kmi? All of the clutch/hydraulics were replaced 600 miles ago, stored in a warm/dry garage. Pedal felt fine, until the last 100 mile. Of course, that was in Oct. Maybe I just need to drive it more.