Brake Master Cylinder Rebuild
01-12-2021, 10:46 PM
#17
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Rich
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hacker-pschorr (01-13-2021)
01-14-2021, 06:32 PM
#19
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They can rebuild them. How do you determine if the brake booster needs to be rebuilt? Mine has rusty outer shell but what I can see inside ( I removed the MC) is pristine.
Are the four bolts behind the dash? Do I have to remove the pod to get to them or can I get to all 4 with just the knee shelf removed? If I can get to the bolts, do I grab the plunger with vice grips on the outside of the booster or between the booster and firewall?
Are the four bolts behind the dash? Do I have to remove the pod to get to them or can I get to all 4 with just the knee shelf removed? If I can get to the bolts, do I grab the plunger with vice grips on the outside of the booster or between the booster and firewall?
01-14-2021, 08:35 PM
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They can rebuild them. How do you determine if the brake booster needs to be rebuilt? Mine has rusty outer shell but what I can see inside ( I removed the MC) is pristine.
Are the four bolts behind the dash? Do I have to remove the pod to get to them or can I get to all 4 with just the knee shelf removed? If I can get to the bolts, do I grab the plunger with vice grips on the outside of the booster or between the booster and firewall?
Are the four bolts behind the dash? Do I have to remove the pod to get to them or can I get to all 4 with just the knee shelf removed? If I can get to the bolts, do I grab the plunger with vice grips on the outside of the booster or between the booster and firewall?
Getting the booster out from between the guard and the motor is the tricky bit. It is a very tight squeeze, at least on a RHD car but it is doable.
01-18-2021, 02:34 PM
#21
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Hi gang,
two questions.
How do I know if my brake booster needs to be rebuilt? I had a leak from MC and have sent it to be rebuilt. What brake fluid should I use DOT 3 or 4?
two questions.
How do I know if my brake booster needs to be rebuilt? I had a leak from MC and have sent it to be rebuilt. What brake fluid should I use DOT 3 or 4?
01-19-2021, 06:41 AM
#22
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The other failure mode (which is more common and safer) is that the diaphragm inside fails and no longer holds vacuum.
That can be caused by age or the MC failing and dumping brake fluid into it. These ones can be rebuilt.
Truthfully the last question depends on your driving, but DOT 4 has a higher boiling point and the cost difference is moot.
You should flush your brake circuit anyways so the car will be fine with whichever.
01-19-2021, 09:59 AM
#23
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AWill new ATE boosters are about 300.00,
if possible buy a new ATE MC as well,
use ATE fluid
if possible buy a new ATE MC as well,
use ATE fluid
01-19-2021, 12:27 PM
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If it is highly rusted just replace it. They're fairly cheap and I wouldn't want to risk it splitting in half and losing my brakes.
The other failure mode (which is more common and safer) is that the diaphragm inside fails and no longer holds vacuum.
That can be caused by age or the MC failing and dumping brake fluid into it. These ones can be rebuilt.
Truthfully the last question depends on your driving, but DOT 4 has a higher boiling point and the cost difference is moot.
You should flush your brake circuit anyways so the car will be fine with whichever.
The other failure mode (which is more common and safer) is that the diaphragm inside fails and no longer holds vacuum.
That can be caused by age or the MC failing and dumping brake fluid into it. These ones can be rebuilt.
Truthfully the last question depends on your driving, but DOT 4 has a higher boiling point and the cost difference is moot.
You should flush your brake circuit anyways so the car will be fine with whichever.
Thanks for the info. I’m going to order booster. I’m putting in new SS lines so I’ll have to flush anyway.
01-19-2021, 03:11 PM
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While waiting on my brake parts, I want to change the oil. Can I start my car (to warm up oil) with the MC removed or will this cause fluid in lines to be pushed out of MC connections?
01-20-2021, 02:31 PM
#27
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While waiting on my brake parts, I want to change the oil. Can I start my car (to warm up oil) with the MC removed or will this cause fluid in lines to be pushed out of MC connections?