Pktrusty

I have a 2014 Corvette z51 82k miles with the manual transmission. I was shifting yesterday on the way home. Clutch pedal fell to the floor. I can pull it out and it will stay all the way with no pressure. Slighted bit of push and it pops to the floor. My fluid looks dirty but it appears not to be leaking. Would the master cylinder leak if it was bad?

I was able to drive it home without a clutch so I know the clutch is good. I read some places on the internet that said to ranger change the fluid. Not sure I will have time to get to it today. Should I just plan on changing the master or try to bleed it first? Not super thrilled if it is the slave.

Luzifer

For sure it's not just the fluid, a seal busted so either the slave or the master.

Pktrusty

Is there anyway troubleshoot the master short of changing it? I guess if it the slave I am in for a decent sized job.

I recently bought my C7 so the little research I have read says you have to pull the engine to change the slave? That cannot be right? At that point I might as well change clutch and all that too since I will have it out.

hisvett

Do this first; use a Turkey baster to suck out all the old fluid, refill with fresh then have a seat and push the clutch in and out at least 30 times. The clutch fluid will turn black, rinse and repeat until the clutch fluid stays clear. The most likely problem is you clutch fluid has not been serviced for a few years and is long overdue. This issue is very common for M7 cars that don't follow servicing all car fluids. What happens is the clutch dust works its way into the slave via the actuation of the clutch rod traveling in and out, carrying clutch dust particles past the O-ring seal into the slave fluid reservoir. This will gum up slave piston and causing it to stick.....hopefully this will fix your problem, otherwise it's a very costly fix having to pull the drive train to get to the slave cylinder.

Good luck!

Pktrusty

I sucked the fluid out and replaced it. I don’t think any of the fluid is cycling. I only had to cycle it 3 times before it was clear. The second time it was almost clear but I couldn’t get it all out with what I was using.

if it isnt cycling at all. It has to be the master no? If the slave was stuck, wouldn’t the pedal have pressure still and near impossible to press down unless I had a leak?

NortonCO

I also think this may be more than just a fluid problem. You can, however, do better than the Ranger method... Move over Ranger Method! DIY clutch fluid flush tool

Good luck!

Avanti

No, it's not fluid. Something else is happening. Is the clutch actually releasing properly when the pedal goes to the floor, correctly or otherwise?

Pktrusty

The clutch pedal is just for looks at this point. Pushed all the way down, it doesn’t disengage the clutch.

If I press the clutch in with the reservoir cap off, I should see the level change or movement? Nothing is happening.

CB56

I haven't owned a Corvette long enough to know exactly how the clutch pedal works the cylinder but I would think there would be linkage under the dashboard. Maybe take a light and a mirror and look under there and see if something came undone.

hisvett

Sounds like you may have a stuck piston in the master if the fluid isn't cycling (moving). Every other time I have seen this problem, we have been able to work the issue out by changing out the fluid. I'm guessing because it has been a very long time since the clutch fluid had been changed, all that clutch dust has had a chance to concentrate around the piston(s) and act like a gummy mix to seize it all up. if the clutch was coming apart and binding up, the slave would still be working, just without resistance because it isn't pushing against any clutch springs and the master would show signs of moving fluid.

Not knowing your mechanical experience, if this was my car, I would pull the master off and check out the movement (or lack of movement) of the piston. Using only brake fluid, clean the piston and master cylinder, do not use brake clean, thinner or another kind of petroleum product. This will swell the rubber and majorly muck up everything. If the master is working OK, then you have a more complicated ($$$$$) problem that will probably require a shop.

And the comment about checking the clutch linkage???? on a Hydraulic system.....really???

Good luck, let us know how it goes and what was needed to be replaced.

Pktrusty

I think you are right. I couldn’t find a replacement part in my town and the soonest I could get it is Thursday. I was going to open it up and see about getting it running but figured I will wait till I have a part to replace it with. I will keep you updated.

CB56

Yes really. There has to be some sort of linkage under the dash that works the rod to the hydraulic reservoir.

RCollier

I have been using the Ranger method on our factory ordered 2016 since the car was new. Out of curiosity I purchased the items for this alternate method and found there to be no change at all. If the Ranger method is done regularly it is all that is needed. Our car is approaching 58K so should provide a good longer term example. The fluid that was forced out from 16" down the line was clean.

NortonCO

I'm glad you're happy with the Ranger method. Unfortunately, my experience aligns more with @C5Natie than yours. I did the Ranger method followed by this and, as shown in the video, it removed more tired and dirty fluid from the line.

Hawkbarr

Norton is correct. Ranger method is 90-95% effective, but the C5Natie method gets more of the older gunk out.(its forced out vs siphoned out).

Hawkbarr

4thC4at60

Have you checked the clutch return spring? I had that fail on a couple cars over the years....unusual I know, but that's what happened....

Pktrusty

Stupid issue and maybe I will ask for some guidance. I got it tore apart and the master cylinder had rotated out. I got it spun in but and the clutch is working. It says now to engage clutch to start. Is there a fuse or something that probably went bad? I don’t see a sensor on the master cylinder that could have been damaged.

Also, I don’t believe I got it all the way out snapped in. Yep I was trying to rotate it from the inside without marginal success. Any recommendations?

NortonCO

I haven't done this level of maintenance on my C7 but, for other vehicles on which I've worked, sensors/switches like this were located inside the passenger cabin, under the dash, as part of the clutch pedal (rather than master cylinder) assembly.

Pktrusty

I disconnected the battery negative for 10 my na and issue went away. Was able to start the car.

SnowyATX

Nice job, I’m impressed you could get it rotated much at all from the inside. I replaced the master a while back and it was a huge pain rotating it completely from the outside. At least when on jack stands. Maybe easier to get to on a lift at just the right height.

Some reference pictures.