Brake Question

[Pirate69]

I have a weird brake question that is scratching my head.

Is the clutch master cylinder connected to the brake system in any way?

I have a 1995 Ford Ranger XL 4.0 6 cyl with manual transmission


The breaks recently went out on it and barely made it around the block, no stopping of vehicle

I changed both wheel cylinders in rear, brake boost, and couple of lines thought were leaking.

Refilled, bled all wheels till got clean fluid, and adjusted rear brakes

still leaking just under and behind booster assembly at a 90 degree fitting that goes into clutch master cylinder

I got pressure when engine is off and out of gear. Brake fluid leaks off bottom of clutch master cylinder.


But i lose brake fluid from brake master cylinder reservoir not clutch master cylinder reservoir

no brake fluid leaking inside of cab

almost seems like a blow seal or O ring some place


Any ideas


thank you



Chris

 

[RonD]

No, no connection between the brake and clutch systems

Pull brake master away from booster and see if there is any fluid in there, if so master seal is leaking
The booster just has air inside no fluid

Brake line coming out of master can have a pin hole leak, so when applying the brakes, pressure in the line squirts fluid out to firewall and clutch master
There is no pressure in brake lines until pedal is pressed down

Have some one press down on brake pedal while you move your hand around between brake lines and firewall
Stream like that is INVISIBLE so you have to feel it before you will see it


So the clutch reservoir is not losing fluid?
There is also no pressure in the clutch line when pedal is not pressed

So you kind of need a helper to press pedals while you look for leaks
But a stick on the pedal and against the seat can work, just don't poke a hole in the seat, lol

 

[Pirate69]

No, no connection between the brake and clutch systems

Pull brake master away from booster and see if there is any fluid in there, if so master seal is leaking
The booster just has air inside no fluid

Brake line coming out of master can have a pin hole leak, so when applying the brakes, pressure in the line squirts fluid out to firewall and clutch master
There is no pressure in brake lines until pedal is pressed down

Have some one press down on brake pedal while you move your hand around between brake lines and firewall
Stream like that is INVISIBLE so you have to feel it before you will see it


So the clutch reservoir is not losing fluid?
There is also no pressure in the clutch line when pedal is not pressed

So you kind of need a helper to press pedals while you look for leaks
But a stick on the pedal and against the seat can work, just don't poke a hole in the seat, lol

 

[Pirate69]

Thank you for the help and information. I did replace booster, and also master cylinder.

Eventually found the problem.

One of the lines that comes off the power brakes box for front passenger disk brake was bad.

Hard to detect where at first.

On line going down, there is piece looks like little filter screen in line, and after that fitting line rubbed through and was corroded.

Could not see at first and was a pin leak.

Everytime you turned on engine, and booster pump, step on brake pedal is when would spray and leak fluid.

Thank you

 

[RonD]

Good work

Hard problem to find, thanks for posting THE FIX

 

[Pirate69]

Good work

Hard problem to find, thanks for posting THE FIX

Yeah was not easy to find.

I dont know how it rubbed thru, there were no lines around it.

Was like a pin hole leak, right at bottom base of what looks like a strainer part - had plastic shielding around it.

Its 3 / 16 tubing, so difficult to actually pinpoint, till cut and examined further.

Top part of tubing rubbed away and lefft pinhole opening