WHY....Master Brake Cylinders fail. Here is why they do. Internal Leakage in a Master Cylinder 

This was very informative. Thank you for this video. I was wondering why my breaks went out completely almost causing me to create a 10 car pile-up, (luckily, with quick thinking i ran off the road into a soft patch of grass). But yeah, thank you for showing me that this failing can cause that. Something so small can cause damage in so many ways.

I love a PROJECT at 77 years old . My 2008 Citroen brake master cylinder had gone bad .. the seals were simply worn . a new €6 euro service kit brought the AS NEW braking performance back . fabricating a vacuum brake bleeding unit and a bench bleed set up kept me amused for a couple of days . using a FLEX HONE 360 carborundum brush to restore the cylinder finish to as new . great video .. if only I could get my head around producing videos for you tube .

Much appreciated!

Now thats a good video you got their mr. Thanks

EXCELLENT video. Thank you for taking the master cylinder apart and explaining everything. I just took mine off and it just doesn't seem to look bad. In fact, my part looks better than the remanufactured part I just paid $90 bucks for. I appreciate your time and knowledge.

Great vid, thanks!

good info. subscribed.

Thanks Dude! We owe you a beer! Best of luck!

Awesome video. Been considering taking mine apart but I had no clue what was in there. Went to a junk yard and pulled one tore em both apart and used the good stuff. Good brakes now tho

interesting indeed. learned alot about how a master works. thank you...

Excellent video

Thank you nice to know it’s that simple I work with wood but I’m gonna start working in Greece

Really good video

Thanks for your content and hard work pal

No other place would I have found the "without ABS" symptom info for my 1988 Cherokee until it landed right if front of my eyes. Thanks!

Really great video for us younger guys, Thanks a lot 🇦🇺

Greeting. Just watched your video. Very helpful. I have a 1999 Ford Expedition and I'm having the same exact problem. I wanted to know why my break pads went to the floor. Thanks.

Yes it is an thank you hopefully ill be able to get it fixed..nicely Illustrated an video display was clean an clear

Thanks

Very will put. I understand fully. Thanks

Thankyou Sir👏

Great video! Unfortunately, I recently acquired a 1978 vehicle and cannot find a rebuild kit for it anywhere. :(

Helpful

I feel the same way about repairing parts I hate throwing them in the trash knowing that it could be repaired...

Try to preserve your old parts. What they're selling these days is garbage

Yep. Same with starter motors. Used to be able to go to the parts store and get a new bendix kit for $7. Now they just want to charge you $150 for a complete reman unit.

My new master cylinder is going to cost $70 that really is a bummer for a $5 part / seal you can buy to replace it but they don't sell just to seal if they did you have to order it online and take forever to get here hopefully you get the right one thanks for the video.

👍👏👏👏👏Thank❤

I'm sure they could make a Viton or silicone seal or something that would last a million years but then it would be TOO well built. Sigh. I bought a rebuild kit and will be doing that today on my 1987 Jeep Comanche. Brake pedal goes to the floor although the truck stops, it feels wrong. I know from my 25+ yrs of driving that it's bad seals inside the master.

Sir wish to ask a question. As shown in video a seal in nick from edge. Is it by setting Brakel shoe with too little clearance. What is your opinion?

Question, my friction plate wont disengage when pedal is fully depressed. Flywheel, friction plate, pressure plate and concentric slave + bearring are replaced 2 months ago and have done 2500miles with them without any problem. The problem started occuring when a friend of mine launched my car from a standstill and wanted to shift to 2nd. I've checked the shifting mechanism, bleeded but none worked. In first gear with clutch pedal depressed to the floor and accelerating the car creeps forward when close to redline. The slave cylinder moves out instantly when I'm depressing the clutch pedal, also it doesn't slip What i did notice is the level in the clutch resevoir is decreasing when the pedal is depressed and raises again when releasing (no leaks under the car or at the pedal)

I have micro bubbles in the back part of brake master cylinder reservoir when the brake pedal is pumped. A hissing noise is also heard then goes away as brake pressure us built. Brake fluid seeps out of reservoir cap after going for 10km+ drive. Is this a sign of failing master cylinder??

When pumping on brake pedal, I made mistake by using heel instead of toe when I felt the pedal got firm/hard. The result was I heard a crack sound coming from under the dashboard. Moment later, the pedal got spongy. The fluid level doesn't change, only its color changes. I am worried that I have something broken either on brake booster (push rod) and/or master cylinder. I want to check parts connected from brake pedal to the booster first. I need to adjust the pedal height as well. But these things seems to require removing the dashboard to get access. Do you have video on how to do these things ?

great video, very informative and interesting. Is it not possible to buy a generic o-ring and rebuild?

Hey! Maybe you could assist me with my problem! I have a 93 fordf150 my brakes work fine however the fluid just pours out right by the proportioning valve where the brake line is. It's almost cheaper to buy a whole new set master cylinder instead of just the proportioning valve. Any advice

One question, what are these seals called for searching, master cylinder seals?

So, for the sake of a 20p washer buy a new cylinder for £400, seems like a con to me !!!!

I have 2006 kia sportage that is losing break fluid. Change pads and rotors on all 4 tires. Still leaking brake fluid but i can not find where its leaking at. So if its a problem with the master cylinder where does the fluid go then because im stumped

What if I have abs I changed all calipers and brake pads bleed all the lines still goes to the floor but I have some brakes

You have a whole perfectly fine master cylinder except for the little seal that is broken, It's just sad you have to replace the whole thing.

Important to mention… When the piston is in the rest position, the brake fluid will be balanced via The compensation hole. This compensation hole is very small, clean this compensation hole with a very thin wire of copper, if it would clog… you are guaranteed a dragging caliper, this has already happened to me twice!!! with the Honda CBX 1000. Stay Safe.

Having checked all parts of system this was only part to need replace

What if there is no air coming out of your calipers, you have a squishy brake and an ABS system. I did activate the pump motor in the ABS while bleeding each cylinder there doesn't seem to be any air but yet I still have a squishy brake.

The seal kits can still be purchased through a brake & clutch specialist as I had to rekit a PBR brake master cylinder in my Dads 2000 model Holden Commodore a couple of days ago. The kit cost $44 AUD. The kit wasn't a PBR brand & Holden don't stock the kits for them,him & my brother thought that the fluid was getting dirty & the brake pedal was spongy due to air getting sucked in through the grommets on the reservoir & it was leaking fluid from there. It wasn't, it was leaking from the lid seal & the grommets were bone dry,the front brakes weren't getting enough fluid due to the proportional valve being stuck inside the master cylinder valve body,it had water contamination in it therefore the valve rusted slightly inside the master cylinder. So,it was a 3 hour job to rebuild that one but not without any hiccups, the rear primary valve seal was an O ring in OEM form & the wiper seal from the kit leaked a tiny bit of fluid so I refitted the original O ring to stop it from leaking. So,it would be wise to find an O ring to suit if the original one leaked. Secondly, I was losing fluid when I refitted the unit,it was leaking from the brake failure warning switch so I pinched an O ring on the proportional valve. The valve was hard to pull back out as the O ring bound up inside the master cylinder, once I removed it,I replaced the O ring then reassembled the master cylinder. The brakes are far better than what they have been in years, my dad bought one from a wrecker to fix the sponginess problem, what are the odds that one had the same problem ???? They were both the same !!!! Fitting one from a wreck didn't fix the problem, rekitting it did !!!!

That's what I figured happened to mine. There are no leaks at the calipers, nor at the brake line where it meets the cylinder. Pedal sinks to the floor. Initially, you get a good brake, but you wait long enough it sinks, 'cause one of the seals is breaking the vacuum. Like trying to use a syringe with a bad gasket.

thanks

My brake has been sinking.. Fluid was low, topped it off, got better but the brake sank again, I figure bleeding any posdible air out to trouble shoot would be easiest to rule out but it doesn't seem to want to come out anymore even after pumping the brakes.. So I imagen a bad seal could be the reason it's not pumpin these brakes

How would you get the pistol out if it’s stuck inside?

I got a 91 ford f350 7.5 is this the same thing. What if the brake fluid is still full in the reservoir. And brake pedal still goes all the way to the floor.

In my case my truck has no ABS but when I was approaching a stop sign I applied the brakes the truck flew right past it. Checked all wheels for leaks, the master cylinder reservoir it still at normal level, so gotta be an internal leak in the master cylinder.

wish you had some overhead lighting in the beginning!hard to see what you were doing?!

Where does the fluid go from the master cylinder due to the internal leakage?

HELP-04 Civic LX all brake pads changed,all wheels bled,but seems like only the back drum brakes are stopping my car.. Brake Pedal is normal when the car is off but when the car is started up the pedal goes to the floor WHY???? anyone HELP

What happened to the old days when you could purchase an overhaul kit (seals and plungers) instead of the entire assembly.

Mine Doesn’t go to the floor but it’s getting softer ... any suggestion. Don’t really wanna throw money in parts which I don’t need... unfortunately I have abs

I looked up a master cylinder repair kit for my GM car. It exists, but the kit sells for MORE than the cost of a replacement master cylinder.

I have a jeep I call Frankenstein because it is pieced together from several other types of vehicle. As long as the bolts match up to the firewall, can I use pretty much any master cylinder?

I got a Ford with ABS TCS. Brakes sink with no problem, to the floor. I replaced the Master Cylinder and bled the system. STill to floor. I then replaced the ABS unit with a used one. Brakes still went to floor. Found leak in line of the ABS. The flare was bad iin one line. I then replace that ABS with a new abs this time. Still brakes go to floor after bleeding brakes. . I dont see any leaks. Any ideas? Could the rebuilt master cylinder be bad?

Replaced front pads by pushing caliper pistons back in...now no pedal pressure. Did it tear a seal ? How could this have happened ? Car is 15 yrs old BTW.

To bad you cant rubber wield it to fix it like you can wield plastic

..yep, a little nickel part will cost you $50.00+. That's the case with most all plastic & rubber parts now. They will last a few years, maybe...

What about leaking at the rear seal at the booster? I have had two aftermarket cylinders fail like that and they were brand new. I ended up using my oem because it was in better shape.

when the leak is internal, where does the fluid go? my fluid level drops over time but i dont see no leak anywhere around. so i wonder where its going?

I rebuilt my master cylinder with brand new seals because bubbles was coming from my Reservoir and pedal keep going to the floor. Why bubbles still coming from the new seals?

The burger cylinder is easy to bleed but a pain to remove

They do make master cylinder rebuild kits--I was today years old when I learned this, lol. I saw for my 2003 Matrix it was about 10 to 20 bucks for a rebuild kit and about 30 bucks for a new master cylinder.

Where u still able to bleed the brakes? Was there full resistance with the car off but sinking when turned on ir did it sink when it was off also? Having some trouble,my pedal gets full resistance when car off,but gets floored when turn on car

Hi TVWXMAN32, I have a 2000 Hyundai Elantra, no ABS. The brakes are locking up intermittently in stop and go traffic for the last few months. So, I removed the front tires. The brake pads were locked solid and the rotor wont rotate at all. Front-driver side brake and wheel was blistering hot, front-passenger side was less hot. Back brakes were not hot. When the wheel/brake lock up, the brake pedal is stuck at the up position, brake becomes super sensitive, the car drags and just touching the brake stops the car. Pressing with a lot of force wont make the brake pedal go down, it stays stuck at up position for 10 minutes even with the engine off. 15 minutes after turning the engine off, the brake pedal would go down a little bit. After 30 minutes everything becomes normal, the brake pedal goes down and up normally, the car drives normally afterwards for the rest of the day. The car also runs louder than before. Rotating the steering wheel to the right diminishes the road noise partially. People gave me a big list of things that could be causing this. After this locking issue started happening, over the last few months I replaced the following parts: 1. New brake pads and shoes on all 4 with new hardware. 2. New rubber brake hoses in both front brakes. 3. New wheel cylinders in both back brakes. 4. New caliper with piston assembly in front driver side. Passenger side is fine. 5. New wheel bearing in front driver side (there was visible smoke from front driver wheel when it first happened). Other bearings are fine. 6. New cheap Chinese tires on all 4. 7. Bled a large bottle of new brake fluid through the system. There are no leaks. None of the above fixed the problem. Any ideas what may me be causing this intermittent brake locking issue?

I got a honda year 2000 and the break goes all the way down i changed the master cylinder it still goes all the way down any idea what it can be?

You can buy a rebuild kit, however it costs the same for a rebuilt master cylinder from auto parts store!!.

Ok, how does the reservoir come off?

My Chevy brakes near floor. Could it be the master cylinder?

Hello, just an update, my master cylinder went on my 2008 Lexus, cost £300, + labour! Must be cheap in U.S.A.?

What does it mean your stopped at a red light then the pedal slowly goes to the floor and starts coasting

1995 F series, (not super duty ,F600-F800, F53, or F59) had Rear Antilock Brake System (RABS) You can buy a rebuild kit for Ford. www.amazon.com/Raybestos-MK1849-Professional-Master-Cylinder/dp/B000C71MP8/ref=sr_1_1?ie=UTF8&qid=1518388688&sr=8-1&keywords=MK1849

So I can repair my 2009 optra Chevrolet brake cylinder now

Did you say seal kit?! only about 40x.......UGH!!!

What happens if you do have ABS and the break goes to the floor?

Can a master cylinder cause your truck to not stop?

What does it mean when the fluid drains and you pedal goes to the floor but you can feel your car stopping but not completely? Any suggestion can help, just needed to fix so I can go to work again Edit: no leaks on the line or brakes

It's not "sad", it is plain and simple GREED. They make you buy the way overpriced part that probably won't last as long as the original.

So, if the rebuilds are supposed to be so great, why do they have crap warranties?

خوب

Amazon cylinders don't work And the seals look good😢😢😢😢Same with autozone O'Reilly's all those places Brand new and they don't work

They sell so many rubber gaskets. can't we improvise?

you can by from europa

That happened to a penguin who was out driving in the countryside, so he stopped at the next garage he could find. He left the car with the garage owner to fix it, then went for a walk around town. On his way back to the garage, he bought an ice cream. When he got to the garage, the owner said it looks like he has blown a seal, the penguin said, no, no, I have just eaten an ice cream.

Just a waste of money now a days on these new pieces of shit cars this right here is a easy they just love to have people waste money on stuff