Brake Diagnostic Tips! Common Reasons Why Your Disc Brake Upgrade Doesn’t Work. 

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I wasted 5 bottles of brake fluid trying to bleed brake lines. No matter what I did, the pedal remained spongy with no pressure. Eventually, I switched left and right calipers to make bleeder point upwards, and thanks to this guys, it worked like magic. Thanks a bunch.

So I have a problem when I slam on the brakes it will not stop on time. Still rolls. Almost ran over a Crack head crossing the street. Lol.. 1957 f100 ,crown vic front suspension 8 inch booster and 1.125 mastercylinder.

Thank you thank you thank you. Put on a new master cylinder and no brakes. I had the brake pedal in the lower hole and not the upper. You are the only RU-vidr to address this.

Very interesting and so true that after doing the conversion, brakes sucks like mad, worse than even before. Here, i have a 79 Trans Am did a 4 wheels discs conversion. Everything new. Pedal feels good and firm after bleeding. Then when you start the engine, pedal goes to the floor. Switch off the engine, pedal goes back up with firm feel. Start engine, goes to the floor. So what is going on here.

Bravo! Well done. Just the facts.

My brake travel is fine. However, my brakes just don't lock up. I can push down as hard as I can and it still just gradually stops. Kinda scary.. the thing that is annoying is I bought the car like this and I have no idea about anything. I upgraded first the booster thinking it was that, then master cylinder with 1 inch bore and still same thing. All brakes have no air in them. Not really sure what to do now

Good stuff. Ive had faulty master cylinder right out of the box. Fluid was bypassing the push rod. And it was getting just enough fluid between the master and booster to cause soft pedal. Big headache chasing that down to discover faulty right out of the box...

Thank you for the video! Some nice tips in there. Wondering what you think about my problem… (74 F100) originally manual brakes front disk rear drum. Brakes were great other than not having a booster. Went ahead and got a booster and master kid they make for my truck and upgraded to a rear disk kit made for the truck. (I did not reinstall the factory proportioning valve) problem I’m having is the pedal doesn’t want to return to the “neutral” position, but it does realms most of the way so I just lift it the rest of the way with my foot. I did notice that the rear disks are not engaging (I have an adjustable proportioning valve I can install) , but could that be my pedal issue? Seems to also want to stick more once I’ve been driving a few miles. Any thoughts would be appreciated!

This video solved a lot of questions on my 78¨ Toyota Jeep disc conversion. The breaks where weak on 4 drum originally. I changed front to disc but stilled weak. Then I changed the master cylinder for 1¨inch bore and got a little better but it needed more braking power. I checked the original workshop manual and figured out that it had a 10lb retention valve for the rear brakes so I'm planning to get it and try again .Thanks for sharing your tips!

A question I have is: vacuum bleeding the front brakes on my 2001 dodge ram works fine.. but not the rear brakes; the brake lite came on the first and last time I tried it .... it obviously off-balanced the combination valve; should I hold off the metering valve or maybe keep the brake pedal pressed while vacuum bleeding the rear brakes..if anyone knows? thank you I wont try it again unless I can be sure

Great informative tutorial and demonstration video Brother

Another good tip would also be when doing brakes if your vehicle has abs be very careful trying to bleed a abs system is a pain if the abs module runs out of brake fluid it can also cause major problems hydrolocking the brake system

I have a soft pedal all the time. Car off, soft. Car on, still goes to the floor. Got the right stuff brake kit for 68 Camaro and went with the Non-Ebrake kit for the rear. I have no idea where to start. The mechanics I have left it with cant figure it out. Thoughts? I can elaborate in better detail if needs be.

I see you changed the channel name to match instagram Jeremy Brother love the channel name bro

And some calipers are dual piston and some are quad pistons

I'm changing from a single chamber master cylinder to a dual chamber for safety. I'm wondering if I use a master cylinder, correct bore, from a car that has single piston front calipers will it work with my calipers which are 4 pistons each? Too small and not enough fluid pressure perhaps? Or should I use a master cylinder that comes from a car with 4 piston calipers?

Ok I have a 1990 Toyota 4Runner w/ manual transmission 4x4. I have disc rotors on front, and drum brakes on rear. I use OEM Organic pads. I bled my brakes, my brakes work, no leaks. I don't have ABS. Sometimes when I slowly exit the driveway, I will tap the brakes and one of the rear tires will briefly lock up and release, leaving a 8" streak/tire skid in the driveway. Its random, it can be one wheel or the other rear wheel with drum brakes. It only happens at very low speed. Any ideas? I have new dot 3 brake fluid, I never mix synthetic with conventional brake fluid. I have that Load Sensing Proportional Valve in the rear on the vehicle. Its 34 years old, original. Could it be that? Its not my wheel cyl, they are new. They are OEM and I changed them myself, thiinking they were problematic. But they are not. The master cyl is original. But my brakes are working.

I have a 65 impala that had 4 wheel drums.. I bought a front disc brake conversion kit for a couple grand $$$ from Wilwood. After I bought that I discovered I needed an upgraded master cylinder and bought one from CPP. Then life got in the way as it commonly does for a lot of us, and everything sat in their boxes for for a couple years. I eventually got back on task and got everything installed. This included new brake lines. Got everything bled and took the car for a test drive. Brakes worked but I really had to put my leg into it. I read in some forums that you need to use a proportioning valve lock during bleeding. This threads into the brake light circuit on the proportioning valve and prevents the proportioning valve safety feature from actuating and cutting off brake fluid from the side it perceived has a leak. This helped little for me. Then I read for any application using manual brakes (me), a master cylinder with a bore less than 1 inch is a MUST. My master cylinder is 1 1/8". So I just got a power booster. I really hope it does the trick.

I swapped over to disc brakes and found that the small diameter brake booster.( 9 inch), required 17 inch's of vacuum to work properly, I only have 12 at idle, so I hooked up a vacuum canister & vacuum gauge to monitor it, when it drops below 17 inch's my pedal is hard, above 17 and it works perfectly, I should note that it does drop 5 inch's every brake application so on occasion I have to "burp" the throttle to create vacuum, wife hates that lol

Great video...going to put that info to work soon. Dad's 33 Ford Sedan brakes (pedal action) is hard as a rock with very little travel. He's running the typical mix rear drums disk front (9in caliper) with booster. Car is an old build so I'm not sure what he bought for a mc/booster. Believe ill start by swapping the master. Thoughts?

Great video!

U corrected my problem, thanks 😊

Very well done and accurate video with some good tips. One more note on the booster push rod, if adjusted too long, it will make the brakes drag. My experiences... the last few vehicles I worked on, as far as bleeding, it seems as if the master is fully bled, the systems have gravity bled by themselves (non ABS). For example, if I change a bad line, I cap off the port with a plug like you show, then bend and create my new line based off the old line profile and install the new line by removing the temp plug. This keeps the master cylinder full while you make the line up. After the new line is installed, I then open a bleeder at the end of that circuit and wait. I keep an eye on the fluid level in the master and add as necessary until the fluid runs out the hose I put on the bleeder. I also change my systems fluid by doing the same, one bleeder at a time. You can watch the dirty fluid slowly leave the reservoir. Grease on the threads also helps future removal of the bleeders!

I did power disk break on my 65 impala and they worl for about 3 4 stops then they lock up and i have to releave bleeder nut for them to release what should i look at everything els is right ...frame off restoration and i want to drive it already with out worries

HELP!!!! So I replaced the master cylinder and booster on my 1957 Ranchero. After bleeding the system and with the engine NOT running I had great pedal pressure with no fading. However, once I started the engine, the pedal would go all the way to the floor with no resistance at all. Very frustrating…. What’s the dang deal??? (This Ranchero had a front disc brake conversion a few years ago.) Someone…. Please help!!

I've done a disc brake conversion with hydroboost I have no rear brake I've adjusted calipers changed master and hydrobust moved brake pedal to bottom hole still nothing any advice thanks

Kinda a good Vid bud . Doin a 56 chev 2 door wagon . What diameter , brak line do you suggest front and rear m converting to front disc , with s-10 calipers , and stock 56 rear wheel cylinders? Hope t9 hear back

T I havea 2014 Honda Accord every time I change all pads and rotors it only takes a little while for it to feel like my brakes are not catching sometimes it feels smooth and tha. Others it feels like it's braking I. To nothing as if my brakes already word down, could this be the master cylinder. I'm in my 3-4 brake pads and rotors and still.having this issue

Hi Mate, great video. I have rebuilt the master cylinder in my 69 camaro wit hfront disck and I just cant bleed my brakes.. I have even lossened the two lines from the master cylinder and I get a very little oil comming out. what could be the issiue. The master cylinder goes into a Proportional valve and then into a metering valve. The pedal feels stiff but I dont get any pressure or oil comming out of the master even thou I crack the lines at the master cylinder.

I put CCP Firewall power brake up grade on my 55 Chevy truck. Never have been happy with them. One more tip is to use a proportion vale tool when bleeding. It keeps the rod from blocking off F or R. Putting in a new rear hose today just to eliminate it. I like the plug idea.

The brakes on my car are very much Frankenstein. I have calipers from a Pontiac boneville, rotors from a Toyota previa, and a custom bracket. It worked for a bit but they lock up.

On my 62 with disc brakes conversion it has only one line coming out of the proportioning valve (top small hole) and tee to both front caliper’s the bottom hole is plugged , could that be a problem?

i have a 70 impala my pedal is solid until i hook booster up to carbutrator then its drops to ground i did install a mild cam but im lost whats the problem, i just order reserve canister for now ..... but video is very helpful

Great advice

Great video... One question: How does one re-center the pressure differential valve as it got triggered while bleeding my brakes and I didn't know about the block off plug? 🤔

purchased a 67 lemans ...with disc conversion Brakes HARD AS HELL TO PUSH/STOP..WHAT SHOULD I LOOK FOR FIRST.

Very helpful, thank you!!

Excellent video! Thank you.

Great advice! Thanks for sharing!

Thanks for the video, helpful

Very good way to diagnose a break system i agree with these steps

Dont the old 4 wheel drum brake master cylinders keep residual prrssure?

I put big brake kit on it wildwood

I was wondering if my 455 442 1969 motor will operate my disc brakes?

Good tips.

😦😦you sure wont feel good if you dont have brakes when you step on that pedal😭