6 votes
Accepted

How does the brake fluid return to reservoir in Disc Brakes after brake pedal is released?

In the caliper, the seal is designed so when you press the brake pedal and fluid enters, the seal twists sideways. When you release the brake pedal, the force of the seal pushes the piston and thus ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
6 votes

Brakes don't work

If your brake pedal went to the floor it means that there was not enough hydraulic pressure to apply the brake. If they were working fine before and never felt squishy then your master cylinder has ...
rviertel's user avatar
  • 1,169
4 votes

brakes wont bleed after replacing lines from mc back 98 gmc jimmy

With that much line replaced, it's going to take some effort to bleed. Somebody has to sit and pump the brake, while somebody else works each bleeder nipple starting at the furthest from the MC (...
SteveRacer's user avatar
  • 12.4k
4 votes
Accepted

Stripped Thread: Motorcycle Brake Lever Master Cylinder

After examining your added photos, here is how I would do it: Remove the entire assembly, and clamp it well in a vice. Obtain the proper drill size for the tap you will need, from a really rough ...
SteveRacer's user avatar
  • 12.4k
3 votes
Accepted

Brakes are still soft. Do I need a new ABS Pump? 07 Mazda 3

Just thought I'd quickly update you on the situation. Put it simply, it's now fixed. It was indeed the ABS pump, and bought a used one on ebay for 55 dollars and I replaced it at home on my driveway. ...
Jonathon's user avatar
  • 181
3 votes

Work involved in changing master cylinder and brake booster on 1972 Mustang

1972 Flat Rate data is a bit difficult to come by, even from a fossil like myself that never throws anything away. For a 1982 Mustang 5.0 V8, book is around 2 hours labor. The engine compartment is ...
SteveRacer's user avatar
  • 12.4k
3 votes

Stripped Thread: Motorcycle Brake Lever Master Cylinder

A thread repair kit: helicoil, timesert, quicksert would be the correct way to repair it. Since this is a pretty low torque application, it's possible to repair with the epoxy like JB Weld or ...
Eric's user avatar
  • 564
3 votes

Is it okay for master cylinder to be crooked (leaning to left) on aftermarket power brake booster?

What the ?? For a repair like that something is definitely wrong. What exactly is causing the off kilter position? For the brake system to operate correctly the "linkage" driving the master cylinder ...
zipzit's user avatar
  • 6,559
3 votes
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Sudden complete brake failure

If there were a simple and obvious answer to this riddle, such as low brake fluid or a gross brake fluid leak, one can assume that any mechanic who has been in business more than 15 minutes would have ...
MTA's user avatar
  • 5,935
2 votes

How do I check the brake fluid in master cylinder of my car?

To check the brake fluid in your master cylinder, follow these steps: 1. Open the brake fluid reservoir on top of your master cylinder of your car: If you have the kind with a little plastic bottle ...
PARTS AVATAR-CANADA's user avatar
2 votes

Clutch problems

By what you describe its highly unlikely that the clutch is at fault here.. To me too it sounds like either the clutch master cylinder is sticking or the clutch pedal mechanism is at fault.. Or ...
Orb's user avatar
  • 5,057
2 votes

Motorcycle Brake Lever - Soft Feel & Long Pull

The cause of a soft brake lever is one or more of (a) air in the brake lines, (b) tired brake lines that expand as brake fluid pressure increases when the brake lever is pulled, (c) failing master ...
DavidRecallsMonica's user avatar
2 votes

Brakes don't work

If you have fluid in the brake reservoir, and have no pedal, you have a failed master cylinder. The piston that moves when you step on the brake pedal has o-ring seals that if they fail, can allow ...
Phil C's user avatar
  • 51
2 votes

Unable to bleed brakes 87 nissan 300zx

Because there are no external leaks and the brake pedal now doesn't go to the floor but (sometimes) is soft, either a) air is still trapped in the brake system, or b) one or more of the car's flexible ...
DavidRecallsMonica's user avatar
2 votes
Accepted

Brake master cylinder rubber seals - replaceable or not?

You posted two links to images of master cylinders and then asked, This cylinder has some sort of rubber seals, whilst this one doesn't look to have them or they're a different color and hard to ...
dwizum's user avatar
  • 1,134
2 votes

How is lost fluid replaced when bleeding brakes?

Examine the drawing carefully as its drawn with the brake pedal in home position (up or to the left in the drawing) with both piston chambers open to the reservoir. When pedal is pressed, both feed ...
F Dryer's user avatar
  • 976
2 votes
Accepted

How is lost fluid replaced when bleeding brakes?

Note the shape of the rubber seals in the master cylinder in your diagram. They are designed so that they expand and seal tightly when the pushrod is being pushed but they will collapse slightly and ...
jwh20's user avatar
  • 12.1k
1 vote

Front passenger brake keeps sticking at random

Possible causes: Overfilled reservoir. Warped disc or incorrectly installed calipers or pads (e.g. sliders not sliding). Do proper test of manually spinning the wheels jacked up. Engine off and on. ...
bretddog's user avatar
  • 153
1 vote
Accepted

Does a diameter of a brake line affect braking pressure

According to Pascal's law, pressure must everywhere be equal. Pressure is defined as a force on a surface. Pressure equals force devided by area P = F / a. That is, the area of the master and slave ...
user60481's user avatar
  • 1,334
1 vote

How to drain a brake booster

You'll need to remove the booster from the fire wall of the vehicle, then drain it out, then use some acetone to clean it out. Let it dry, then re-install. If it continues to work correctly, you're in ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
1 vote

Brake master cylinder rubber seals - replaceable or not?

$150 really isn't that much. Yes, seals can be replaced. Most brake master cylinders can be overhauled, depending on the model kits are often available with replacement seals, springs and the like. ...
GdD's user avatar
  • 16.4k
1 vote
Accepted

Unable to bleed brakes 87 nissan 300zx

reaction disk..... this took way to long to figure out
Wazy's user avatar
  • 131
1 vote

Container holding brake fluid is bubbling

It's boiling.. time to change your brake fluid! Brake systems aren't completely sealed - and brake fluid is hygroscopic so over time moisture works it's way into the fluid (either through flexing on ...
motosubatsu's user avatar
1 vote
Accepted

Why would my brake pedal go halfway to the floor before the brakes engage?

you have lost fluid any number of ways such as 1) if the pads become worn, there is more space for fluid inside the caliper, and this can cause it 2) The master cylinder could be leaking or the ...
steve's user avatar
  • 26
1 vote
Accepted

Gasket between master cylinder and brake booster?

There is a gasket that sits between the master cylinder and the brake booster. It is a thick rubber gasket that fills the space between the two parts and fits snugly around the master cylinder shaft. ...
Fred Wilson's user avatar
  • 11.6k
1 vote
Accepted

How do I bleed the master cylinder and check the booster for fluid?

As another user mentioned, you will need to be absolutely sure that fluid isnt leaking from any other location at all. If the hose burst caused the current cylinder to empty out, you will want to try ...
Mustangguy809's user avatar
1 vote

What vehicle does this master cylinder and booster go too

Well, I haven't been able to find anything good. Then best advice I can give is these 2 options: Find what is "factory stock" for the '66 C10, and work your way backward from there. That's not a very ...
kyle_engineer's user avatar
1 vote
Accepted

Clutch Peddle Pops Down When Barely Touched and Doesn't Return

The mentioned symptoms (no pressure on the clutch pedal) normally would indicate air in the circuit, so I would then recommend a flush. In your case the description of an oil drop on the cylinder ...
Martin's user avatar
  • 8,448
1 vote

Pass-through hydraulic hand brake cylinder

Theoretically what your proposing will work with two caveats. The size of the compensation port. When the master cylinder is "off" there is a port that allows brake fluid to circulate from the ...
vini_i's user avatar
  • 16k
1 vote

Work involved in changing master cylinder and brake booster on 1972 Mustang

I am not familiar with the setup of your mustang, but I am going to assume it is similar to other booster/master setups I've seen. Here are the approximate steps you would follow. Disconnect battery....
rpmerf's user avatar
  • 8,443

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