Drill Mod for sticky clutch...help?
Thread Starter
Le Mans Master
Joined: Sep 1999
Posts: 5,464
Likes: 2
From: Private
Drill Mod for sticky clutch...help?
Can someone describe the drill mod in some detail. Interestingly, I had the problem about 2 years ago, replaced the MC and it went away. We'll it came back and on the Pocono East course the other week, I was stuck in 3rd the whole time.
I drove it on the street afterwards and hot or cold, when I nail the throttle, sure enough the pedal sticks to the floor and I can't switch gears.
Took it to the dealer to have them fix again, but I have heard the "drill mod" solve the problem quickly and easily.
If not, does bleeding the fluid help ease the problem as a temporary fix? I have the SCCA track event THIS Friday and don't want to get stuck in 3rd gear on the long course.
I drove it on the street afterwards and hot or cold, when I nail the throttle, sure enough the pedal sticks to the floor and I can't switch gears.
Took it to the dealer to have them fix again, but I have heard the "drill mod" solve the problem quickly and easily.
If not, does bleeding the fluid help ease the problem as a temporary fix? I have the SCCA track event THIS Friday and don't want to get stuck in 3rd gear on the long course.
Instructor
Joined: Aug 2004
Posts: 127
Likes: 0
From: Bethalto Illinois
drill mod
Safety Car
Joined: May 2000
Posts: 4,827
Likes: 352
From: Albuquerque NM
That's a good description, however, there are THREE restrictors between the master and the slave. One at the outlet of the master, one in the hard 90* in the center of the line, and one at the input to the slave.
Instructor
Joined: Aug 2004
Posts: 127
Likes: 0
From: Bethalto Illinois
Drill Mod
(Quote)
That's a good description, however, there are THREE restrictors between the master and the slave. One at the outlet of the master, one in the hard 90* in the center of the line, and one at the input to the slave.
(Quote)
I stand by my post.
Today I took measurements from a used master cyl & the hard line with half the quick disconnect attached.
There is no restrictor at the outlet of the master cyl, I dropped a .195 dia drill bit 2 inches into the outlet of the master cyl.
The hard elbow is pinned to the outlet of the master cyl, the hard elbow has a restriction of .130 dia, it is not in the center of the line.
The quick disconnect is in the center of the line and does have a restriction in it of .096.
I did not measure the other half of the quick disconnect or the restriction at the slave cyl.
To the best my memory serves me, the slave restriction was about .035, I drilled it to about .70.
I did the drill mod as pictured at my first post http://vetteweb.com/tech/vemp_0506_clutch/index2.html
along with a clutch change, the slippage stopped and it engages firmer now.
Norm
That's a good description, however, there are THREE restrictors between the master and the slave. One at the outlet of the master, one in the hard 90* in the center of the line, and one at the input to the slave.
(Quote)
I stand by my post.
Today I took measurements from a used master cyl & the hard line with half the quick disconnect attached.
There is no restrictor at the outlet of the master cyl, I dropped a .195 dia drill bit 2 inches into the outlet of the master cyl.
The hard elbow is pinned to the outlet of the master cyl, the hard elbow has a restriction of .130 dia, it is not in the center of the line.
The quick disconnect is in the center of the line and does have a restriction in it of .096.
I did not measure the other half of the quick disconnect or the restriction at the slave cyl.
To the best my memory serves me, the slave restriction was about .035, I drilled it to about .70.
I did the drill mod as pictured at my first post http://vetteweb.com/tech/vemp_0506_clutch/index2.html
along with a clutch change, the slippage stopped and it engages firmer now.
Norm
Safety Car
Joined: May 2000
Posts: 4,827
Likes: 352
From: Albuquerque NM
Sounds like they have changed parts. Mine were new, 2002, Z06 master, slave, and line. The hard 90 was in the middle of the line, not at the master, and there were three restrictors I drilled out.
If they have changed to only one restrictor, that alone is a good thing.
If they have changed to only one restrictor, that alone is a good thing.
Melting Slicks
Joined: Jan 2000
Posts: 3,029
Likes: 1
From: Wichita KS
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Originally Posted by NLKoerner
(Quote)
I drilled it to about .70
Norm
I drilled it to about .70
Norm
You must have meant .070Don't remember what size I drilled mine, but I know it wasn't that big
BTW My hydraulics had several resrictions also
Instructor
Joined: Aug 2004
Posts: 127
Likes: 0
From: Bethalto Illinois
[QUOTE=Flyin'Brian]WOW big hole: You must have meant .070
Don't remember what size I drilled mine, but I know it wasn't that big:
OOPS
.070 is correct.
Late night or typo??
as I said, from memory,,,,, but not .7, thanks
The point I intended to make, but did not, is the smallest restriction is at the slave and any increase should be made at the slave.
The other restrictions are larger than what you can drill the slave restriction.
Also my info only covers 97 thru 01, sorry for any confusion.
Norm
Don't remember what size I drilled mine, but I know it wasn't that big:
OOPS
.070 is correct.
Late night or typo??
as I said, from memory,,,,, but not .7, thanks
The point I intended to make, but did not, is the smallest restriction is at the slave and any increase should be made at the slave.
The other restrictions are larger than what you can drill the slave restriction.
Also my info only covers 97 thru 01, sorry for any confusion.
Norm
Last edited by NLKoerner; Jun 16, 2006 at 03:06 AM.
Pro
Joined: Jun 2005
Posts: 593
Likes: 1
There is a difference in a restriction that effects the flow in either direction or a orfice that is by slave that allows faster flow to the slave but less when pedal is being released.
It is there so newbies would not kill engine when at a stop on upgrade in road where you could back up on pedal and it would hold car from rolling backwards.
It is there so newbies would not kill engine when at a stop on upgrade in road where you could back up on pedal and it would hold car from rolling backwards.
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