[Fg2si8880]

Hello everyone,

So about a yr ago my friend volunteered to flush my brake system when he was replacing my clutch and ever since my brake pedal never felt the same!

I've taken the car to 4 different places to get it re-bled and only got small improvements but the problem still there. I no longer have a stiff brake pedal, it would travel the to the floor. The car will stop but it's not confinement inspiring and it's not consistent with the feel. Meaning every press will feel different.

What you guys recommend i do next? Change the BMC? What could possibly happened?

Including a video to show how the pedal travel. Ignore the engine noise. It's getting swapped out.

 

[FD7683]

When he flushed the system did he run it dry by any chance?

 

[ArcadeTechGW]

A couple of questions:
1. 4 wheel disc brakes or front disc rear drum?
2. Was any other work done (e.g., pad replacement on rear drum?)

This looks like a brake system with rear drum brakes that did not have the adjuster turned out properly.

That, or a damaged master cylinder o-ring or scored cylinder, which is allowing fluid bypass.

 

[Fg2si8880]

When he flushed the system did he run it dry by any chance?

Thanks for reply. I actually don't know 😕

 

[Fg2si8880]

A couple of questions:
1. 4 wheel disc brakes or front disc rear drum?
2. Was any other work done (e.g., pad replacement on rear drum?)

This looks like a brake system with rear drum brakes that did not have the adjuster turned out properly.

That, or a damaged master cylinder o-ring or scored cylinder, which is allowing fluid bypass.

The car is a si with rear disc brakes. No pads or rotors replaced at the day he flushed the system. Afterwards i did replace the pads and rotors and tried numerously to bleed the system but the problem remained, coud he have possibly damaged something?

 

[ArcadeTechGW]

The car is a si with rear disc brakes. No pads or rotors replaced at the day he flushed the system. Afterwards i did replace the pads and rotors and tried numerously to bleed the system but the problem remained, coud he have possibly damaged something?

It sounds like a damaged / cut o-ring in the Master Cylinder.

 

[roaussie]

Hello everyone,

So about a yr ago my friend volunteered to flush my brake system when he was replacing my clutch and ever since my brake pedal never felt the same!

I've taken the car to 4 different places to get it re-bled and only got small improvements but the problem still there. I no longer have a stiff brake pedal, it would travel the to the floor. The car will stop but it's not confinement inspiring and it's not consistent with the feel. Meaning every press will feel different.

What you guys recommend i do next? Change the BMC? What could possibly happened?

Including a video to show how the pedal travel. Ignore the engine noise. It's getting swapped out.

Most likely air in the system, needs bleeding properly. Make sure it doesn't run dry while doing it or it sucks air back in so you have to start all over again

 

[Fg2si8880]

Thanks everyone for your response.

 

[x08csi]

Did you relube the slides and piston when you did the pads? one of mine was froze up on my last pad change.

 

[Fg2si8880]

Did you relube the slides and piston when you did the pads? one of mine was froze up on my last pad change.

No i never done that, but it's good to know. I will do it on my next brake pads swap.

 

[Fg2si8880]

My brakes still feel soft and mushy. I went to test drive another si today and it was day and night difference. What do i do next? Swap the master cylinder?

 

[ArcadeTechGW]

Bleed all 4 brakes first.
Make sure you get solid fluid, not air.
If you do that, and are good, then I'd suggest replacing the master cylinder.

Are ANY fittings seeping brake fluid? That would also be a problem.

 

[Fg2si8880]

Bleed all 4 brakes first.
Make sure you get solid fluid, not air.
If you do that, and are good, then I'd suggest replacing the master cylinder.

Are ANY fittings seeping brake fluid? That would also be a problem.

No, i don't have any leaks anywhere in the system. And yes i already bled it today and i was getting clear fluid with no air.

I ordered a used oem master cylinder from ebay today. I will post an update once i install it.

 

[ArcadeTechGW]

No, i don't have any leaks anywhere in the system. And yes i already bled it today and i was getting clear fluid with no air.

I ordered a used oem master cylinder from ebay today. I will post an update once i install it.

Okay. Remember, you'll have to bleed all 4 brakes after you replace the master cylinder. You can minimize that by putting the right caps over each brake line as you remove it.

I think you'll find a cut o-ring or dead o-ring in your old master cylinder. It allows the brake fluid to slip by, and gives you a mushy feel. At least, that's what it sounds like.

 

[krishay.baxter]

Make sure it doesn't run dry while doing it or it sucks air back in so you have to start all over again






Nox Vidmate VLC

 

[Fg2si8880]

So we installed a new brake master cylinder, new ss brake lines and bled the system but the problem remains! Any advice on what to do next? This has been frustrating, my car is excellent everywhere and handling is amazing with the upgrades i done, but sadly no brakes! :/ a friend was even suggesting dumbing away the chassis and get another one but i think that's crazy since the brake system is an external piece of the chassis!

Please guys help, I'm located in the bay area Cali, if you know anyone can fix it lmk.

 

[ArcadeTechGW]

So we installed a new brake master cylinder, new ss brake lines and bled the system but the problem remains! Any advice on what to do next? This has been frustrating, my car is excellent everywhere and handling is amazing with the upgrades i done, but sadly no brakes! :/ a friend was even suggesting dumbing away the chassis and get another one but i think that's crazy since the brake system is an external piece of the chassis!

Please guys help, I'm located in the bay area Cali, if you know anyone can fix it lmk.

Did you adjust the rear drum brakes so that the adjuster has the pads so tight, the drum barely fits on?

That is the answer to this issue more often than not. People think they need to put the adjuster all the way down and back up - it doesn't work like that.

 

[Fg2si8880]

Sometimes you gotta say goodbye to your brake pedal feel in the 8th gen platform. 🫂👋🥲 goodbye, It's been nice knowing you!

 

[FD5]

I am curious to know what kind of brake fluid you're using? and what brand?

 

[ArcadeTechGW]

This is interesting.

So you have:
replaced the lines
replaced the master cylinder
bled the brakes

And still no brakes?

Let's start with the basics. The front brakes provide at least 80 to 90% of the braking.

Put the front end up on jackstands.

Start moving the tire by hand. Now have someone in the car hit the brakes.

If the tire keeps moving, you have bad calipers. The piston is stuck.

If this happens, let's do some basic troubleshooting. Pull the left front wheel off. Look for any fluid dripping on the disc. Also, are the discs clean and free of any lubricant (grease, oil)? If you see any, clean it off with an oil cutter like acetone or something similar.

You'd probably have to replace the pads at that point too.

No leaks, pull the caliper off the disc, and have someone press the brake pedal and see if the pads move. Don't have them press it hard - window down, and tell them to slowly press the pedal and stop if you say anything (or you could blow the puck out).

No movement of the piston - bad caliper.

I've also seen people use that stupid radiator stop leak and then blow a hose. That crap causes the rubber in hoses to expand, so if you have done that and the blowout hit any of the rubber brake lines, look for seepage on the outside of the lines. If you smell that (not dusty, looks oily is a bad sign) replace the rubber hoses.

How about posting some pictures?