Brake nightmare!

[Kustomvida90]

The unfortunate issue is most new GM/Delco masters are now or have long been defunct. So it's either Chinesium or a rebuilt unit, or NOS GM. And that's only as good as the manufacturer/rebuilder. Cheap components and process mean cheap quality. Never mind the price isn't so cheap anymore for anything.

Even if you did find an NOS master cylinder, it's been on the shelf so long, it MAY not work, either. From my eperience, they're not dry when they put them in the box, but over the years, how long could it sit there without ever being used? It might be ok, or it may not.

Either way, when bleeding, I advise using that center pin tool.

I went thru 3 ac delcos , and now I’m using a raybestos unit .. you’re right about the quality , I remember back then the masters felt and looked good and sturdy ! Now a days they feel all fragile lol

 

[Kustomvida90]

Were these 'bad' master cylinders each 'bench bled' before installing into the car? Four in a row suggests the issue is possibly elsewhere.

Yes , the first 3 were bench bled using the hose in the reservoir technique and the last one was bled with the hose technique and the syringe method ..the first 2 Mc leaked at the base , and the last 2 were for testing .. one thing they all had in common was the bubbles in the reservoir.. I made sure to buy them new and not refurbished to avoid any problems/defects ..
I do agree with you about the problem not being the master cylinder ,, I’m loosing sleep trying to figure out the issue

 

[scoti]

Yes , the first 3 were bench bled using the hose in the reservoir technique and the last one was bled with the hose technique and the syringe method ..the first 2 Mc leaked at the base , and the last 2 were for testing .. one thing they all had in common was the bubbles in the reservoir.. I made sure to buy them new and not refurbished to avoid any problems/defects ..
I do agree with you about the problem not being the master cylinder ,, I’m loosing sleep trying to figure out the issue

I feel your frustration. This could possibly be a simple thing that's just being overlooked because it's just an item not expected. Enter the Murph....


Murphy's First Law: Anything that can go wrong will go wrong.

Murphy's Second Law: Nothing is as easy as it looks.

Murphy's Third Law: Everything takes longer than you think it will.

Murphy's Fourth Law: If there is a possibility of several things going wrong, the one that will cause the most damage will be the one to go wrong.

Corollary: If there is a worse time for something to go wrong, it will happen then.

Murphy's Fifth Law: If anything simply cannot go wrong, it will anyway.

Murphy's Sixth Law: If you perceive that there are four possible ways in which a procedure can go wrong, and circumvent these, then a fifth way, unprepared for, will promptly develop.

Murphy's Seventh Law: Left to themselves, things tend to go from bad to worse.

Murphy's Eighth Law: If everything seems to be going well, you have obviously overlooked something.

Murphy's Ninth Law: Nature always sides with the hidden flaw.

Murphy's Tenth Law: Mother nature is a b*tch.

Murphy's Eleventh Law: It is impossible to make anything foolproof because fools are so ingenious.

Murphy's Twelfth Law: Whenever you set out to do something, something else must be done first.

Murphy's Thirteenth Law: Every solution breeds new problems.

Murphy's Fourteenth Law: If anything can't go wrong on its own, someone will make it go wrong.


If Murphy's Law can go wrong, it will.

Knowing Murphy's Law won't help either.

Murphy's Law is recursive. Washing your car to make it rain doesn't work.

Murphy's Time-Action Quandary: You never know how soon is too late.

O'Toole's Commentary On Murphy's Law: Murphy was an optimist.

Proof of Murphy's Law: Murphy's Law cannot be proven, yet is correct, as when you try to prove Murphy's Law, you will see that the proof is incorrect. This is obviously due to Murphy's Law, therefore Murphy's Law is correct and proven.

Stewart's Corollary to Murphy's Law: Murphy's Law may be delayed or suspended for an indefinite period of time, provided that such delay or suspension will result in a greater catastrophe at a later date.

Zymurgy's Seventh Exception to Murphy's Laws: When it rains, it pours

 

[Kustomvida90]

Update ..I finally fixed the the gurgling in the master cylinder! After checking and retightening all the brake lines, readjusting drum brakes , re- bleeding the master cylinder and bleeding the entire system it’s finally has stoped … I still have a soft brake on start up and car still can’t panic stop

 

[1KWIKSIX]

Installing 2 residual pressure valves (one in the front brake line & one in your rear brake line ) will firm up your brake pedal.

Wilwood Residual Pressure Valves

Ideal for drag racing, street rods, and many off-road applications, inline residual pressure valves from Wilwood retain a minimum brake line pressure to help eliminate excessive pedal travel. These 2 lb. valves are used in disc brake applications where the master cylinder is mounted below the horizontal plane of the calipers--in other words, where fluid drainback occurs, causing excessive brake drag. With drum brakes, 10 lb. valves are used to compensate for return spring tension in the drums. Wilwood residual pressure valves are made from billet aluminum and color-coded for easy identification

Wilwood Disc Brakes

MasterCylinder No: 260-3279, master cylinders, aluminum tandem, combination remote, compact master cylinder, go-kart master cylinder, handle-bar master cylinder, rebuild kits, high volume, hvm master cylinder, tandem, bleeding kits

www.wilwood.com

260-1874 - Wilwood 2 lb Residual Pressure Valve - Moser Engineering

260-1874 - Wilwood 2 lb Residual Pressure Valve Master Cylinder Dimensions Wilwood Residual Pressure Valve Drawing Additional Dimensions...

www.moserengineering.com