no brake pressure 71.solution found
Thread Starter
Racer
Joined: Jan 2016
Posts: 419
Likes: 58
From: montreal quebec
no brake pressure 71.solution found
Lesson learned, bought new master, installed and tried everything to get a good pedal, finally thought bad master, pulled it apart. guess what all rubber failed inside....why??? I now know why,
my buddy closed up his shop, brought me tons of fluids, including a gallon of brake fluid, I poured out this fluid into a bowl, it has been mixed with some other fluid, who know what, but
it does not like rubber. lesson learned, buy a new bottle, tried to save $15.00 and now will cost me much more. Mike.
my buddy closed up his shop, brought me tons of fluids, including a gallon of brake fluid, I poured out this fluid into a bowl, it has been mixed with some other fluid, who know what, but
it does not like rubber. lesson learned, buy a new bottle, tried to save $15.00 and now will cost me much more. Mike.
Race Director
Joined: Oct 2000
Posts: 12,683
Likes: 3,136
From: Shamong, NJ
If you used DOT 5, that's probably the reason your rubber seals failed.
A few years ago, the US EPA outlawed the use of certain chemicals that were found in DOT 5. The new chemical make up of DOT 5 has been known to damage the rubber seals used in some master cylinders and calipers. I'm assume the same DOT 5 is likely being sold in Canada now too.
A few years ago, the US EPA outlawed the use of certain chemicals that were found in DOT 5. The new chemical make up of DOT 5 has been known to damage the rubber seals used in some master cylinders and calipers. I'm assume the same DOT 5 is likely being sold in Canada now too.
Melting Slicks
Joined: Mar 2008
Posts: 2,666
Likes: 289
From: Spring Park MN
If you used DOT 5, that's probably the reason your rubber seals failed.
A few years ago, the US EPA outlawed the use of certain chemicals that were found in DOT 5. The new chemical make up of DOT 5 has been known to damage the rubber seals used in some master cylinders and calipers. I'm assume the same DOT 5 is likely being sold in Canada now too.
A few years ago, the US EPA outlawed the use of certain chemicals that were found in DOT 5. The new chemical make up of DOT 5 has been known to damage the rubber seals used in some master cylinders and calipers. I'm assume the same DOT 5 is likely being sold in Canada now too.
As I have said many times here, I have been using DOT 5 brake fluid since the 1970's in everything including street, drag racing, land speed racing and road racing without one single issue. I have it in my current Vette today. I have rock hard brakes that function perfectly.
I have searched extensively for this supposed reformulation issue in the past when someone brought it up on this forum and have found zero info to support it. Nobody else was able to show evidence of it either. The only reformulation info I have found is that DOT 5 was first developed in the late 1960's for the military. It's final formulation was developed in the 1970's and it is still the same formula today.
The two main problems I have seen with DOT 5 are people putting it in systems with DOT 3 in them and people aerating the fluid by pumping the crap out of the brakes while bleeding and then not getting a hard pedal. Both of these are user caused issues, not the fluid.
Mike
Melting Slicks
Joined: Sep 2016
Posts: 3,004
Likes: 104
From: NC
Lesson learned, bought new master, installed and tried everything to get a good pedal, finally thought bad master, pulled it apart. guess what all rubber failed inside....why??? I now know why,
my buddy closed up his shop, brought me tons of fluids, including a gallon of brake fluid, I poured out this fluid into a bowl, it has been mixed with some other fluid, who know what, but
it does not like rubber. lesson learned, buy a new bottle, tried to save $15.00 and now will cost me much more. Mike.
my buddy closed up his shop, brought me tons of fluids, including a gallon of brake fluid, I poured out this fluid into a bowl, it has been mixed with some other fluid, who know what, but
it does not like rubber. lesson learned, buy a new bottle, tried to save $15.00 and now will cost me much more. Mike.
Melting Slicks
Joined: Mar 2008
Posts: 2,666
Likes: 289
From: Spring Park MN
Mike
Race Director
Joined: Oct 2000
Posts: 12,683
Likes: 3,136
From: Shamong, NJ
As I have said many times here, I have been using DOT 5 brake fluid since the 1970's in everything including street, drag racing, land speed racing and road racing without one single issue. I have it in my current Vette today. I have rock hard brakes that function perfectly.
I have searched extensively for this supposed reformulation issue in the past when someone brought it up on this forum and have found zero info to support it. Nobody else was able to show evidence of it either. The only reformulation info I have found is that DOT 5 was first developed in the late 1960's for the military. It's final formulation was developed in the 1970's and it is still the same formula today.
The two main problems I have seen with DOT 5 are people putting it in systems with DOT 3 in them and people aerating the fluid by pumping the crap out of the brakes while bleeding and then not getting a hard pedal. Both of these are user caused issues, not the fluid.
Mike
I have searched extensively for this supposed reformulation issue in the past when someone brought it up on this forum and have found zero info to support it. Nobody else was able to show evidence of it either. The only reformulation info I have found is that DOT 5 was first developed in the late 1960's for the military. It's final formulation was developed in the 1970's and it is still the same formula today.
The two main problems I have seen with DOT 5 are people putting it in systems with DOT 3 in them and people aerating the fluid by pumping the crap out of the brakes while bleeding and then not getting a hard pedal. Both of these are user caused issues, not the fluid.
Mike
Below is a link to the regulation, that Lonestar told me was the one that caused the chemical make up of DOT 5 to be changed.
https://www.regulations.gov/document...2009-0767-0031
Melting Slicks
Joined: Mar 2008
Posts: 2,666
Likes: 289
From: Spring Park MN
I too have used DOT 5 in the past, and with good results, but I'm told that DOT 5 has changed, and I've encountered problems with using new DOT 5. I have 2 customers return caliper sets to me, that had seals that turned to mush, and another who had it happen with a master cylinder. All three of them had just used fresh DOT 5. I have been selling Lonestar's calipers for over 20 years, and never had this happen before the last 2 years. Lonestar, Muskegon, CCSB and others are now including warnings with their brakes, that use of DOT 5 can void the warranty.
Below is a link to the regulation, that Lonestar told me was the one that caused the chemical make up of DOT 5 to be changed.
https://www.regulations.gov/document...2009-0767-0031
Below is a link to the regulation, that Lonestar told me was the one that caused the chemical make up of DOT 5 to be changed.
https://www.regulations.gov/document...2009-0767-0031
Most of the brake rubber damage I have seen has resulted from contact with some sort of petroleum distillate such as solvent, carb cleaner or some cheap brake cleaners that have petroleum in them, which brake cleaners should never have. I'm not sure what happened in your customer's cases, but I have consistently used DOT 5 from the 70's up to this day and have yet to have a problem.
Mike
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Burning Brakes
Joined: Oct 2006
Posts: 1,006
Likes: 28
From: Lutz Florida
As I have said many times here, I have been using DOT 5 brake fluid since the 1970's in everything including street, drag racing, land speed racing and road racing without one single issue. I have it in my current Vette today. I have rock hard brakes that function perfectly.
I have searched extensively for this supposed reformulation issue in the past when someone brought it up on this forum and have found zero info to support it. Nobody else was able to show evidence of it either. The only reformulation info I have found is that DOT 5 was first developed in the late 1960's for the military. It's final formulation was developed in the 1970's and it is still the same formula today.
The two main problems I have seen with DOT 5 are people putting it in systems with DOT 3 in them and people aerating the fluid by pumping the crap out of the brakes while bleeding and then not getting a hard pedal. Both of these are user caused issues, not the fluid.
Mike
I have searched extensively for this supposed reformulation issue in the past when someone brought it up on this forum and have found zero info to support it. Nobody else was able to show evidence of it either. The only reformulation info I have found is that DOT 5 was first developed in the late 1960's for the military. It's final formulation was developed in the 1970's and it is still the same formula today.
The two main problems I have seen with DOT 5 are people putting it in systems with DOT 3 in them and people aerating the fluid by pumping the crap out of the brakes while bleeding and then not getting a hard pedal. Both of these are user caused issues, not the fluid.
Mike
My 1971 uses Pentosin Dot 4. That was what was in it when I got it and no reason to change. The Pentosin Dot 4 is pricey compared to other Dot 3 and 4 fluids.
Last edited by stock76; Oct 16, 2018 at 09:31 PM.