Take Care of Your Clutch--Preventing or Curing Pedal Issues
02-15-2009, 03:11 PM
#41
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Questions:
1.) Does this mean that it's too late for me? In other words, do I already have a case of "Clutch Fluid" syndrome, which will require the car to be sent to the shop?
2.) If so, is this something covered by Warranty
Now that I've watched your vid, I will make sure to stay on top of this much more frequently.
1.) Does this mean that it's too late for me? In other words, do I already have a case of "Clutch Fluid" syndrome, which will require the car to be sent to the shop?
2.) If so, is this something covered by Warranty
Now that I've watched your vid, I will make sure to stay on top of this much more frequently.
Ranger
02-15-2009, 10:52 PM
#43
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St. Jude Donor '06-'07
Also, I noticed in your video that there was a bottle of GM clutch fluid and a bottle of prestone, yet I noticed that you only used the clutch fluid. What was the prestone for?
02-15-2009, 11:05 PM
#44
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Since mine is completely black, how often should I do this until the color is clear? Daily, weekly, monthly?
Also, I noticed in your video that there was a bottle of GM clutch fluid and a bottle of prestone, yet I noticed that you only used the clutch fluid. What was the prestone for?
Also, I noticed in your video that there was a bottle of GM clutch fluid and a bottle of prestone, yet I noticed that you only used the clutch fluid. What was the prestone for?
The Prestone shown is a viable alternative, if the GM-brand shown isn't available conveniently.
Ranger
Last edited by Ranger; 02-16-2009 at 12:37 PM.
02-16-2009, 04:46 AM
#45
I hate doing this so I've only been doing it every few months or so. It's never been black, but it does get darker.
This is only my second stick shift car. Do they all have this problem?
Some of my own notes -
1. I tried using a turkey baster, but the residual dot4 eventually melted the plastic! So I went back to the mixer syringe.
2. I keep a dot4 can inside a plastic ziplock in my trunk, stowed amongst a bunch of towels and things. I've noticed that it can seep out from under the cap. Where it's touched the label of the can, the paint has dissolved. The ziplock hasn't dissolved though.
3. My dad (vetterodder) warned that when you use the syringe, be careful not to suck it out of that straw-sized opening at the bottom, because you might introduce an air bubble in there when you pour the clean fluid in. So I always leave a tiny bit in the bottom of the reservoir.
4. The person who invents a mod or something that eliminates this problem could sell it for a good profit.
This is only my second stick shift car. Do they all have this problem?
Some of my own notes -
1. I tried using a turkey baster, but the residual dot4 eventually melted the plastic! So I went back to the mixer syringe.
2. I keep a dot4 can inside a plastic ziplock in my trunk, stowed amongst a bunch of towels and things. I've noticed that it can seep out from under the cap. Where it's touched the label of the can, the paint has dissolved. The ziplock hasn't dissolved though.
3. My dad (vetterodder) warned that when you use the syringe, be careful not to suck it out of that straw-sized opening at the bottom, because you might introduce an air bubble in there when you pour the clean fluid in. So I always leave a tiny bit in the bottom of the reservoir.
4. The person who invents a mod or something that eliminates this problem could sell it for a good profit.
02-16-2009, 12:24 PM
#46
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St. Jude Donor '09-'11
Thanks for info. I'd been concerned about this almost since I took delivery in July. I changed it yesterday (first time) at 7 months/4300 miles. It was completely black, and had been for a long time.
A bunch of changes knocked it down to a brownish color, after which it took the the rest of the 12 oz Prestone bottle and half of another one until it finally stayed clear after pumping the pedal.
I had tried on Sat. to get the GM fluid, but oddly enough it was ridiculously hard to find and list price was about 3 times as much as the Prestone DOT 4.
Thanks to the video, I finally understood how the presure relief insert inside the cap was supposed to be folded up. When I got the car, it was unfolded and crumped up inside the clutch fluid reservoir.
A bunch of changes knocked it down to a brownish color, after which it took the the rest of the 12 oz Prestone bottle and half of another one until it finally stayed clear after pumping the pedal.
I had tried on Sat. to get the GM fluid, but oddly enough it was ridiculously hard to find and list price was about 3 times as much as the Prestone DOT 4.
Thanks to the video, I finally understood how the presure relief insert inside the cap was supposed to be folded up. When I got the car, it was unfolded and crumped up inside the clutch fluid reservoir.
02-16-2009, 01:57 PM
#47
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I've done this a few times. The 1st time the fluid was NASTY and crud on the underside of the cap. I didn't know about this on our C5. That had to be extremely dark fluid when traded at 33K miles.
02-16-2009, 06:52 PM
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Fluid Flow between Master and Actuator (Slave) Documentation
Brought over from a the Autocross/Roadracing board from a parallel thread on the topic.
Hi Rob.
It’s always a good idea to go to the source document for a definitive description of the operation of the clutch hydraulics. In this case the Corvette Service Manual 2006, Volume 3, page 7-360, and I quote:
The clutch hydraulic system consists of a master cylinder and an actuator cylinder.
When pressure is applied to the clutch pedal (pedal depressed), the pushrod contacts the plunger and pushes it down the bore of the master cylinder.
In the first 0.8 mm (0.031 in) of movement, the recuperation seal closes the port to the fluid reservoir tank, and as the plunger continues to move down the bore of the cylinder, the fluid is forced through the outlet line to the actuator cylinder mounted to the driveline support assembly.
As fluid is pushed down the pipe from the master cylinder, this in turn forces the piston in the actuator cylinder outward.
As the actuator cylinder moves forward, it forces the release bearing to disengage the clutch pressure plate from the clutch disc.
On the return stroke (pedal released), the plunger moves back as a result of the return pressure of the clutch.
Fluid returns to the master cylinder and the final movement of the plunger opens the port to the fluid reservoir, allowing an unrestricted flow between system and reservoir….
There you have if from the source.
Summary: Clutch fluid circulates between the master and actuator (slave).
Note: The volume of fluid in the entire system is a very few ounces. One ounce is in the master cylinder reservoir until diminished as you depress the pedal and create the flow described above.
Hope that helps.
Ranger
Ranger, just to be 100% clear, you're saying that the clutch fluid circulates? As you pump the pedal, a fluid molecule marches down from the master to the slave cylinder, past the bleeder and then returns to the reservoir? There is a circular path here that traverses most of the system?
It’s always a good idea to go to the source document for a definitive description of the operation of the clutch hydraulics. In this case the Corvette Service Manual 2006, Volume 3, page 7-360, and I quote:
The clutch hydraulic system consists of a master cylinder and an actuator cylinder.
When pressure is applied to the clutch pedal (pedal depressed), the pushrod contacts the plunger and pushes it down the bore of the master cylinder.
In the first 0.8 mm (0.031 in) of movement, the recuperation seal closes the port to the fluid reservoir tank, and as the plunger continues to move down the bore of the cylinder, the fluid is forced through the outlet line to the actuator cylinder mounted to the driveline support assembly.
As fluid is pushed down the pipe from the master cylinder, this in turn forces the piston in the actuator cylinder outward.
As the actuator cylinder moves forward, it forces the release bearing to disengage the clutch pressure plate from the clutch disc.
On the return stroke (pedal released), the plunger moves back as a result of the return pressure of the clutch.
Fluid returns to the master cylinder and the final movement of the plunger opens the port to the fluid reservoir, allowing an unrestricted flow between system and reservoir….
There you have if from the source.
Summary: Clutch fluid circulates between the master and actuator (slave).
Note: The volume of fluid in the entire system is a very few ounces. One ounce is in the master cylinder reservoir until diminished as you depress the pedal and create the flow described above.
Hope that helps.
Ranger
02-16-2009, 09:56 PM
#52
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St. Jude Donor '06-'07
Ranger,
I spoke with my service department regarding my situation, to which I explained in detail. I ended my sentence with...is this covered under warranty. He kind of danced around the question and said that it's quite normal for Corvettes. I'm thinking to myself, they're trying to avoid servicing it (should I take that route) because of GM's deadline tomorrow.
Your thoughts/opinions, or advice. I'd like to make sure that I'm fully armed with info if I decided to take her into the shop.
I spoke with my service department regarding my situation, to which I explained in detail. I ended my sentence with...is this covered under warranty. He kind of danced around the question and said that it's quite normal for Corvettes. I'm thinking to myself, they're trying to avoid servicing it (should I take that route) because of GM's deadline tomorrow.
Your thoughts/opinions, or advice. I'd like to make sure that I'm fully armed with info if I decided to take her into the shop.
02-16-2009, 10:27 PM
#53
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Ranger,
I spoke with my service department regarding my situation, to which I explained in detail. I ended my sentence with...is this covered under warranty. He kind of danced around the question and said that it's quite normal for Corvettes. I'm thinking to myself, they're trying to avoid servicing it (should I take that route) because of GM's deadline tomorrow.
Your thoughts/opinions, or advice. I'd like to make sure that I'm fully armed with info if I decided to take her into the shop.
I spoke with my service department regarding my situation, to which I explained in detail. I ended my sentence with...is this covered under warranty. He kind of danced around the question and said that it's quite normal for Corvettes. I'm thinking to myself, they're trying to avoid servicing it (should I take that route) because of GM's deadline tomorrow.
Your thoughts/opinions, or advice. I'd like to make sure that I'm fully armed with info if I decided to take her into the shop.
Much easier and less risky to follow the protocol on a do-it-yourself basis.
Ranger
02-16-2009, 10:48 PM
#54
Where is the bleeder valve for the clutch?
I'm used to my FBody, and have installed a remote bleeder, so I just use that to flush out my lines, is it possible to do something like that?
- Corvette Newbie
I'm used to my FBody, and have installed a remote bleeder, so I just use that to flush out my lines, is it possible to do something like that?
- Corvette Newbie
02-17-2009, 07:45 AM
#55
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From my files:
Open quote
Bleeding a Clutch Via an Installed Remote Bleeder
Courtesy of “wrencher,” a moderator on LS1Tech.com and a GM Tech by profession
A remote bleeder and Mity-Vac are absolutely essential to making the procedure a one-man operation.
Connect a Mity-Vac to the outlet on the remote bleeder. To ensure a tight seal, apply a little “sil-glide” to the threads on the bleeder
Then drain the reservoir with a syringe. Refill with clean fluid.
Then proceed to pull a vacuum & pull the fluid in normal flow direction w/ the Mity-Vac brake fluid bleeding attachment.
Keep doing it till the fluid comes out clean. Make sure you keep the reservoir at the proper level throughout.
I usually keep an eye on the fluid color & flush by the look of it.
I drag race my car a lot. I flush before and after every track visit.
When I don’t, the pedal changes & I know it's flush time.
I do a fluid change & all is well again.
By following this routine, I’ve kept my master cylinder working correctly for 3-4 years now. Close Quote
I put a remote bleeder on my cars...for the flexibilty of the next owner. For me, swaps via the reservoir are more effective and simpler. The two openings in the clutch actuator (slave) are less than two inches apart. That causes shallow flow during remote bleeding and won't rid the actuator of accumulated crud (clutch dust). That's a central purpose of the full and aggressive pedal pumps in my protocol, to bring the actuator and master crud into suspension and allow the particulate to be evacuated.
But that is the procedure for remote bleeding if you decide it's best for you.
Ranger
Last edited by Ranger; 02-24-2009 at 07:46 AM.
02-17-2009, 01:09 PM
#59
Drifting
I did it... NICE AND BROWN at first... I had to repeat the procedure about 5 times until I lost the brown streaks in my clutch reservoir... I hope this makes shifting smoother...
