Habitforming

I've used the chain method ever since I first got it a decade ago, has always worked fine for me. A misguided friend that borrowed it once replaced the rubber seal in the top because he couldn't get it to seal. No idea what he used or where it came from, but I don't think it was necessary regardless.

You only need about 7-10 psi to bleed the system. I need to go dig up that post where someone used the oem cap. He may have modified it in some way to get a better seal.

Gottabfast

If it's the modulator, an ABS event could cycle the valves and fix the problem. Sometimes on older cars contamination can get into the outlet valve seat, which allows fluid to fill the secondary circuit that is closed under normal braking. When you pump the pedal, it fills the secondary circuit and once the circuit is filled it will build pressure and feel normal. Try an ABS stop or 5 to cycle everything and see if that helps. This condition doesn't cause an ABS code either.

Slowcrash_101

Sounds like a bad booster to me, do you see the paint on the booster flaking off? That would tell you that you have a ripped diaphragm, or the seal to the booster is bad. Remove the vacuum line and see if braking effort is the same.

Gottabfast

If the booster was bad, pumping the pedal wouldn't help. Pedal effort change with pumping the pedal means it hydraulic, not booster related.

Moddiction

I'm thinking there is air trapped in master cylinder or something.


I will buy a new master cylinder since I have such high miles anyways and see how that goes. I bought the power bleeder so ill use that as well to force any air out of system.


Any seals needed to be purchased when swapping my stock brake fluid reservoir over to new master cylinder?

New master cylinder with new lines, calipers, pads, rotors and fluid better fix my braking issue lol.

matt96ex

A new MC is complete with the reservoir.
Be sure to bench bleed the new MC before the install!

Moddiction

I was looking at a centric brand one that does not come with reservoir.

gptoyz

i've tried to eliminate the amount of centric parts I put on my car, I will use a rotor in an emergency

Why not just get a used master cylinder?

Moddiction

Prefer not to buy used as you never know condition of the used part.

gptoyz

There's not much in master cylinder. It's essentially a cast/billet/forged cavity with a plunger/Piston and a nipple - in general

Centric is a crappy Chinese company. So while it may look the same the castings could be weak, a c clip could fail, something super innocuous.

Just look for a low mileage s2k in a wreck and buy a master cylinder. Better than buying some Chinese pos and have it explode and losing all brake pressure.

If a Chinese rotor cracks you will still be able to brake bc there are 3 other healthy rotors. If the master cylinder fails you better hope you have lots of runway to bleed off speed.

Google the failures of knock off brembo radial master cylinders (on motorcycles) - the castings are shit and they will crack or the c clip under tension will fail. The rubber nipple will fly off. Etc