Feb 19, 2015, 01:48 PM
Last edit by: IB Advertising
See related guides and technical advice from our community experts:
Browse all: Brake How-Tos
- How to Bleed Brake System/Change Brake Fluid
Step by step instructions for do-it-yourselfers.
Browse all: Brake How-Tos
brake fluid flush
Thread Starter
Pro
Joined: May 2008
Posts: 670
Likes: 56
brake fluid flush
Exactly how do you flush the brake system on a 93 vett? The FSM says to start at the wheel furthest from the reservoir but if you count the distance from the ABS near the rear axle it seems to be the front pass side wheel? Do you drain the reservoir first somehow? Any other pointers would be appreciated.
And how do you flush the clutch slave?
Thanks
And how do you flush the clutch slave?
Thanks
Drifting
Joined: Oct 2008
Posts: 1,936
Likes: 92
From: Rochester Hills Michigan
Exactly how do you flush the brake system on a 93 vett? The FSM says to start at the wheel furthest from the reservoir but if you count the distance from the ABS near the rear axle it seems to be the front pass side wheel? Do you drain the reservoir first somehow? Any other pointers would be appreciated.
Thanks
Thanks
Safety Car
Joined: Nov 2008
Posts: 4,328
Likes: 15
From: Jacksonville FL
I need to do this too and I will use the gravity method on the brakes. The clutch will require a little more effort. A recent post on this indicates the need to "level" the clutch master cyl by jacking the car appropriately to remove trapped air. The poster used a vacuum pump and did it in 5 minutes.
Le Mans Master
Joined: Mar 2001
Posts: 7,999
Likes: 14
From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
Cruise-In III Veteran
Cruise-In IV Veteran
St. Jude Donor '12
For my brake fluid changes I bought a vaccum bleeder that attaches to my air compressor.
Harbor freight has a hand vaccum pump on sale for about $15
Motive makes a power bleeder that uses pressure at the master cylinder
Get a quart of good dot3 or dot3/4 fluid - I use valvoline synpower
Remove as much fluid as possible from the master cylinder
fill to the neck of the master (this is way over the fill line) put the cap on
Start with passenger rear, crack the bleeder screw, then tighten it.
put the vaccum bleeder on the bleed screw, create vaccum, open bleeder 1/4 - 1/2 turn.
continue to suck fluid until it is clear - if this is the first time you have flushed be VERY careful and check the level in the master often. You don't want it to go much below the "full" line. I've done it a lot so I know how long I can suck fluid out.
Then fill master, do the driver rear, passenger front, driver front.
You will use almost the whole quart!
Then have a helper do the traditional method of slow easy pumps on the brake pedal till hard, crack the bleeder screw, when pedal is on the floor close the bleeder screw
I repeat this between 3-6 times for each caliper. Check the master after each caliper!
Harbor freight has a hand vaccum pump on sale for about $15
Motive makes a power bleeder that uses pressure at the master cylinder
Get a quart of good dot3 or dot3/4 fluid - I use valvoline synpower
Remove as much fluid as possible from the master cylinder
fill to the neck of the master (this is way over the fill line) put the cap on
Start with passenger rear, crack the bleeder screw, then tighten it.
put the vaccum bleeder on the bleed screw, create vaccum, open bleeder 1/4 - 1/2 turn.
continue to suck fluid until it is clear - if this is the first time you have flushed be VERY careful and check the level in the master often. You don't want it to go much below the "full" line. I've done it a lot so I know how long I can suck fluid out.
Then fill master, do the driver rear, passenger front, driver front.
You will use almost the whole quart!
Then have a helper do the traditional method of slow easy pumps on the brake pedal till hard, crack the bleeder screw, when pedal is on the floor close the bleeder screw
I repeat this between 3-6 times for each caliper. Check the master after each caliper!
Burning Brakes
Joined: Sep 1999
Posts: 786
Likes: 31
Cruise-In II Veteran
I believe if you draw a schematic of the brake lines you will find the right front wheel is furthest from the master cylinder, then the left front and a tossup between the rear wheels.
The fluid goes from the master cylinder back to the ABS controller (behind the seats) then to the various brake cylinders.
This is contrary to the traditional brake line setup which didn't have ABS.
The fluid goes from the master cylinder back to the ABS controller (behind the seats) then to the various brake cylinders.
This is contrary to the traditional brake line setup which didn't have ABS.
Safety Car
Joined: Jan 2004
Posts: 3,759
Likes: 8
I believe if you draw a schematic of the brake lines you will find the right front wheel is furthest from the master cylinder, then the left front and a tossup between the rear wheels.
The fluid goes from the master cylinder back to the ABS controller (behind the seats) then to the various brake cylinders.
This is contrary to the traditional brake line setup which didn't have ABS.
The fluid goes from the master cylinder back to the ABS controller (behind the seats) then to the various brake cylinders.
This is contrary to the traditional brake line setup which didn't have ABS.
Thread Starter
Pro
Joined: May 2008
Posts: 670
Likes: 56
Thanks! It sounds like the FSM is telling you to remove the clutch actuator from the clutch housing and hold it horizontal with the bleed nipple facing up, is this really necessary? If someone is pressing the clutch pedal and then you open and close the nipple why do you need to turn it up? Am I missing something obvious here?
I got the brakes flushed, took forever pumping the pedal a little so as not to damage the o-ring.
The fluid in my clutch reservoir looks like the worst gunk I have ever seen, all I did for now was to empty the reservoir and refill it, but I really want to flush it completely. Can I replace the nipple with a solo brake bleeder?
Also I bought 4 earl's solo brake bleeder from summit and they worked great, but next time I am buying a Motive pressure bleeder.
I got the brakes flushed, took forever pumping the pedal a little so as not to damage the o-ring.
The fluid in my clutch reservoir looks like the worst gunk I have ever seen, all I did for now was to empty the reservoir and refill it, but I really want to flush it completely. Can I replace the nipple with a solo brake bleeder?
Also I bought 4 earl's solo brake bleeder from summit and they worked great, but next time I am buying a Motive pressure bleeder.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Race Director
Joined: Dec 2006
Posts: 10,383
Likes: 4
Thanks! It sounds like the FSM is telling you to remove the clutch actuator from the clutch housing and hold it horizontal with the bleed nipple facing up, is this really necessary? If someone is pressing the clutch pedal and then you open and close the nipple why do you need to turn it up? Am I missing something obvious here?
The thing is though that these master and slaves are supposed to be self bleeding. I used a vacuum pump and held the slave upside down and pumped the resevoir dry in only a few pumps and had to do it all over.
When I was done I did a bit of reading and some people were reporting that to bleed the system you only had to make the installed slave level with jacking the car and then operate the clutch pedal 50 times slowly to bleed all the air out of the slave. This makes sense to me since the line in is the highest point when the slave is level. YMMV
Thread Starter
Pro
Joined: May 2008
Posts: 670
Likes: 56
If you want to bleed air I can understand your point but I don't have air in the system only dirt and crud, so I am thinking that I don't need to worry about taking the slave off and holding it however (nipple up), for what I am trying to do wouldn't it be just as good to leave it where it is and pump the clutch, hold it, open the bleed valve, close the valve, release the clutch and then repeat until clear fluid comes out. I think I am right about that but just want to make sure with some of you who have done this and know.
Safety Car
Joined: Dec 2008
Posts: 3,588
Likes: 10
From: North New Jersey
I am going to change my brake fluid also... So let me see if I understand this:
I am going to use my vacuum tool that pulls oil out of boat engines and slip it over the bleeder screw on the brake.
1.) start with the passenger front wheel
2.) start bleeding the brake with the master cylinder cap off making sure the fluid level doesnt get too close to the bottom
3.) when it does fill the master cylinder with new fluid (does the new fluid mix with the old or will it float on top of it?)
4.) when you see the fluid go clear at the caliper then that wheel is bled
5.) repeat at each wheel going from the front passenger to the rear passenger, then the rear driver, then finish at the front driver
Did I miss anything?
How do you make sure you get a full flush and leave no residual fluid (or very little because there will always be some)
Can you just suck all of the fluid out so it is dry and put the new brake fluid in and bleed it?
Thanks
I am going to use my vacuum tool that pulls oil out of boat engines and slip it over the bleeder screw on the brake.
1.) start with the passenger front wheel
2.) start bleeding the brake with the master cylinder cap off making sure the fluid level doesnt get too close to the bottom
3.) when it does fill the master cylinder with new fluid (does the new fluid mix with the old or will it float on top of it?)
4.) when you see the fluid go clear at the caliper then that wheel is bled
5.) repeat at each wheel going from the front passenger to the rear passenger, then the rear driver, then finish at the front driver
Did I miss anything?
How do you make sure you get a full flush and leave no residual fluid (or very little because there will always be some)
Can you just suck all of the fluid out so it is dry and put the new brake fluid in and bleed it?
Thanks
Last edited by dogfish246; May 29, 2010 at 11:23 PM.
Instructor
Joined: Apr 2010
Posts: 154
Likes: 0
From: Miami Florida
Airmotive sells a power bleeder for about $65 that will give you a full flush in about 30 minutes, did mine last week. Use a turkey baster to remove as much fluid as possible mc and start with passanger rear, driver rear, passanger front, and drivers front.
Race Director
Joined: Dec 2006
Posts: 10,383
Likes: 4
Sounds like a good plan.
1. Nope. You've got it.
2. As you said, there will always be a trace of the old left behind.
3. Yes you can but that would involve the more complicated bench bleeding of the master cylinder and would still not remove the trace of old in the system.
2. As you said, there will always be a trace of the old left behind.
3. Yes you can but that would involve the more complicated bench bleeding of the master cylinder and would still not remove the trace of old in the system.
Last edited by 94z07fx3; May 29, 2010 at 11:53 PM.
Cruising
Joined: May 2005
Posts: 14
Likes: 0
From: Gettysburg PA
I just did this flush on my 92. I used a vacuum pump, but one thing I noticed was that the MC volume never seemed to go down.
I would fill it up way over the full line, and it seemed to burp a bit then go down to the full mark, but never dropped below full.
I kept filling it with fresh fluid during the flush.
So I put it all back together (no brake issues before the flush, just dirty fluid), and the pedal is mushy, goes to the floor and brakes are lousy. I never touched the abs bleeder behind the seat.
Obviously I got air in the system, but not sure how.
Any ideas?
I would fill it up way over the full line, and it seemed to burp a bit then go down to the full mark, but never dropped below full.
I kept filling it with fresh fluid during the flush.
So I put it all back together (no brake issues before the flush, just dirty fluid), and the pedal is mushy, goes to the floor and brakes are lousy. I never touched the abs bleeder behind the seat.
Obviously I got air in the system, but not sure how.
Any ideas?
Safety Car
Joined: Feb 2002
Posts: 4,212
Likes: 10
From: Sun City West Az
I just did this flush on my 92. I used a vacuum pump, but one thing I noticed was that the MC volume never seemed to go down.
I would fill it up way over the full line, and it seemed to burp a bit then go down to the full mark, but never dropped below full.
I kept filling it with fresh fluid during the flush.
So I put it all back together (no brake issues before the flush, just dirty fluid), and the pedal is mushy, goes to the floor and brakes are lousy. I never touched the abs bleeder behind the seat.
Obviously I got air in the system, but not sure how.
Any ideas?
I would fill it up way over the full line, and it seemed to burp a bit then go down to the full mark, but never dropped below full.
I kept filling it with fresh fluid during the flush.
So I put it all back together (no brake issues before the flush, just dirty fluid), and the pedal is mushy, goes to the floor and brakes are lousy. I never touched the abs bleeder behind the seat.
Obviously I got air in the system, but not sure how.
Any ideas?
Race Director
Joined: Jan 2002
Posts: 12,263
Likes: 86
From: O'Fallon Missouri
Le Mans Master
Joined: Mar 2001
Posts: 7,999
Likes: 14
From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
Cruise-In III Veteran
Cruise-In IV Veteran
St. Jude Donor '12
Le Mans Master
Joined: May 2005
Posts: 7,360
Likes: 2,281
From: Central Maryland