Warning about brake fluid
Thread Starter
Racer
Joined: Aug 2006
Posts: 415
Likes: 0
From: Utah
Warning about brake fluid
I was driving down a long mountain road thinking I was doing a good job of not riding my brakes so that the fluid wouldn't boil. I didn't downshift, just used my brakes sparingly. Guess what! About the time I got to the bottom of the canyon, my brakes went out. Pedal to the floor and no brakes! I thought I must have sprung a leak in the brake system, wheel cylinder or something. After about 15 minutes my brakes came back, full pedal. I obviously boiled my fluid.
I was baffled as to why the fluid boiled so easily. I have lived near the mountains all of my life, so I know something about driving in them.
The next day on the speed channel,Two Guys Garage or something like that, they explained what the problem was. They said that brake fluid will absorb water vapor from the atmosphere and over time it can get enough water in it to significantly lower the boiling temperature of the fluid. The brakes can easily generate enough heat to exceed the boiling temperature of watered down brake fluid. The answer is to service the brake fluid often enough to keep it relatively free of water.
Since we are all driving C4s that are all at least 10 years old, this advice probably applies to all of us.
Live and learn!!
I was baffled as to why the fluid boiled so easily. I have lived near the mountains all of my life, so I know something about driving in them.
The next day on the speed channel,Two Guys Garage or something like that, they explained what the problem was. They said that brake fluid will absorb water vapor from the atmosphere and over time it can get enough water in it to significantly lower the boiling temperature of the fluid. The brakes can easily generate enough heat to exceed the boiling temperature of watered down brake fluid. The answer is to service the brake fluid often enough to keep it relatively free of water.
Since we are all driving C4s that are all at least 10 years old, this advice probably applies to all of us.
Live and learn!!
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
This is why the brake fluid must be changed out every 12~24 months. With your mountain driving, I would increase that to the 12 month time frame...
I also suggest using Valvoline Synpower Brake Fluid. Nice stuff at a great price. Ford makes a good brake fluid, as does Motal(sp?) and Castrol. But the Motal and Castrol stuff gets real expensive!
I also suggest using Valvoline Synpower Brake Fluid. Nice stuff at a great price. Ford makes a good brake fluid, as does Motal(sp?) and Castrol. But the Motal and Castrol stuff gets real expensive!
Race Director
Joined: Jun 2004
Posts: 13,958
Likes: 707
From: WI
I just bled mine and it did not take very long. My wife pumped the break while I opened the bleeder, she did good! 
Also, sucking the fluid out of the master res. was working, I had been doing just that and expected dirty fluid at the bleeder, it really wasn't to bad.
Also, sucking the fluid out of the master res. was working, I had been doing just that and expected dirty fluid at the bleeder, it really wasn't to bad.
Le Mans Master
Joined: Sep 2003
Posts: 5,874
Likes: 0
From: Littleton CO
This is as good a thread as any to ask: How long before an open bottle of brake fluid (Synpower, specifically) should be judged un-usable? I put braided lines up front a couple weeks ago, but haven't had time to get to the rears yet.
Race Director
Joined: Aug 2003
Posts: 13,421
Likes: 8
From: Lake Mary Florida
Originally Posted by bogus
This is why the brake fluid must be changed out every 12~24 months. With your mountain driving, I would increase that to the 12 month time frame...
I also suggest using Valvoline Synpower Brake Fluid. Nice stuff at a great price. Ford makes a good brake fluid, as does Motal(sp?) and Castrol. But the Motal and Castrol stuff gets real expensive!
I also suggest using Valvoline Synpower Brake Fluid. Nice stuff at a great price. Ford makes a good brake fluid, as does Motal(sp?) and Castrol. But the Motal and Castrol stuff gets real expensive!
Good post.
Drifting
Joined: Mar 2006
Posts: 1,979
Likes: 0
I have mine done every spring when I put the car back on the road.
With it sitting all winter I figure it will be absorbing moisture so in the spring it is bled and I know I have fresh fluid for the summer.
Gary
There is a term for a liquid like brake fluid that will absorb moisture but I can't remember it.
With it sitting all winter I figure it will be absorbing moisture so in the spring it is bled and I know I have fresh fluid for the summer.
Gary
There is a term for a liquid like brake fluid that will absorb moisture but I can't remember it.
Last edited by flyinlow90; Oct 4, 2006 at 10:36 PM.
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Melting Slicks
Joined: Dec 2004
Posts: 2,509
Likes: 756
I buy several small bottles of brake fluid. Once I've opened one, I throw it away. I just don't want to risk moisture contamination.
As for the mountain experience and no brakes, it serves as a reminder that we should make sure our parking brake is in good working order.
Many years ago, I had the brakes serviced in a compact Ford at a chain repair shop and then headed from Florida to North Carolina. Once I got on the interstate highway, I began to notice the brake pedal was going farther and farther down to the floor with each use. Within 30 minutes, the brakes failed completely.
Since I was driving a compact car and was going to be on the interstate highway 98 percent of the trip, I opted to continue the trip with the parking brake as my only brake. I drove 500 miles that way.
As for the mountain experience and no brakes, it serves as a reminder that we should make sure our parking brake is in good working order.
Many years ago, I had the brakes serviced in a compact Ford at a chain repair shop and then headed from Florida to North Carolina. Once I got on the interstate highway, I began to notice the brake pedal was going farther and farther down to the floor with each use. Within 30 minutes, the brakes failed completely.
Since I was driving a compact car and was going to be on the interstate highway 98 percent of the trip, I opted to continue the trip with the parking brake as my only brake. I drove 500 miles that way.
Thread Starter
Racer
Joined: Aug 2006
Posts: 415
Likes: 0
From: Utah
Originally Posted by bogus
This is why the brake fluid must be changed out every 12~24 months. With your mountain driving, I would increase that to the 12 month time frame...
I also suggest using Valvoline Synpower Brake Fluid. Nice stuff at a great price. Ford makes a good brake fluid, as does Motal(sp?) and Castrol. But the Motal and Castrol stuff gets real expensive!
I also suggest using Valvoline Synpower Brake Fluid. Nice stuff at a great price. Ford makes a good brake fluid, as does Motal(sp?) and Castrol. But the Motal and Castrol stuff gets real expensive!
info!!
Burning Brakes
Joined: May 2006
Posts: 763
Likes: 0
From: pa
get a hand vacuum pump to bleed brakes, there cheap and make it a one man operation. i finally broke down after 35 yrs and bought one. i just bled wifes 88 yesterday and worked great. just for the hell of it i looked bleeding procedure....it said....bleed one side of car and then other side.! anybody done it this way before?
Race Director
Joined: Jun 2004
Posts: 13,958
Likes: 707
From: WI
I don't think an open container of fluid could gain moisture any faster then one with the seal still intact. When you pour the fluid out oil gets on the rim, making a nice seal. If the fluid is nitrogen packed, keep it out of the sun. It is very easy to remove the fluid from the fill cap on the car once in a while.
Le Mans Master
Joined: Aug 2005
Posts: 5,002
Likes: 5
From: No Opti Here Tn
St. Jude Donor '06
Synthetic brake fluid doesnt attract water (isnt hydroscopic) is it
I thought that was the advantage
Also I remember that special care has to be taken with the abs on these cars when changing the fluid
I dont have the manual with me but I think it would be wise to use a FSM for this
I could be wrong memory is a funny thing
I thought that was the advantage
Also I remember that special care has to be taken with the abs on these cars when changing the fluid
I dont have the manual with me but I think it would be wise to use a FSM for this
I could be wrong memory is a funny thing
Melting Slicks
Joined: May 2002
Posts: 2,670
Likes: 4
From: Severna Park MD
Originally Posted by 5pinball
get a hand vacuum pump to bleed brakes, there cheap and make it a one man operation. i finally broke down after 35 yrs and bought one. i just bled wifes 88 yesterday and worked great. just for the hell of it i looked bleeding procedure....it said....bleed one side of car and then other side.! anybody done it this way before?
From Chilton the sequence for 84-86 is LR, RR, LF, RF.
From Chilton the sequence for 87 is RF, RR, LR, LF.
So there are three different sequences over the years of the C4.
Last edited by FELNGR8; Oct 5, 2006 at 12:57 PM.
Melting Slicks
Joined: May 2002
Posts: 2,670
Likes: 4
From: Severna Park MD
Originally Posted by 94ZR1
Synthetic brake fluid doesnt attract water (isnt hydroscopic) is it
I thought that was the advantage
The actual advantage of the Synthetic brake fluid is heat tolerance. Synthetic fluid can take more heat from driving abuse before boiling. Valvoline Synpower is 500 degrees. It all is hydroscopic.
Also I remember that special care has to be taken with the abs on these cars when changing the fluid
I dont have the manual with me but I think it would be wise to use a FSM for this
I could be wrong memory is a funny thing
In the Chilton it says for the 92-94 and 95 VIN J (ZR1) to open the ABS module compartment and bleed the main MC line first. I didn't bother with that when I bled mine
I thought that was the advantage
The actual advantage of the Synthetic brake fluid is heat tolerance. Synthetic fluid can take more heat from driving abuse before boiling. Valvoline Synpower is 500 degrees. It all is hydroscopic.
Also I remember that special care has to be taken with the abs on these cars when changing the fluid
I dont have the manual with me but I think it would be wise to use a FSM for this
I could be wrong memory is a funny thing
In the Chilton it says for the 92-94 and 95 VIN J (ZR1) to open the ABS module compartment and bleed the main MC line first. I didn't bother with that when I bled mine
Race Director
Joined: Dec 2002
Posts: 13,348
Likes: 233
From: SCMR Rat Pack'r Charter Member..Great Bend KS
Originally Posted by jrp
This is as good a thread as any to ask: How long before an open bottle of brake fluid (Synpower, specifically) should be judged un-usable? I put braided lines up front a couple weeks ago, but haven't had time to get to the rears yet.
As long as the bottle is tightly capped after you take the fluid from it, it should be good for many, many months. A good-fitting cap is airtight....at least as airtight as the cap on the MS reservoir.
If anyone chooses to throw any left-over fluid away after the bottle is opened, that's okay, too. Won't hurt anything other than your wallet and then only a few bucks worth of "ouch".
PS. Oh, yes, it's spelled M-0-T-U-L.
Larry
code5coupe
Last edited by rocco16; Oct 5, 2006 at 12:16 PM.
Safety Car
Joined: Nov 2005
Posts: 4,590
Likes: 48
From: W MI
I bleed all of my family's cars(6 total, 3 mine) every year. It's one crappy weekend, but somebody has to do it. Usually it's just me and my mom or sister(I don't have a vacuum bleeder) pumping and bleeding away.
80sRule
80sRule