93 Ranger Brake fluid loss

[rw1644h]

My 93 Ranger was running (and braking fine) until the other day. While at an uphill streetlight, when starting off with the brake pedal depressed, the brake pedal went to the floor. Now the brake pedal goes to the floor all the time. Checked the fluid level; it was low. Added some fluid to no avail. Re-inspection of the master cylinder showed the fluid level to be low again. No leaks on the pavement or showing around the area of the four wheels. Any ideas ? Thanks in advance.

[rhandwor]

This is a classic symptom of a master cylinder failure. I would purchase a rebuilt unit and install it. Caution you have to bleed the system. I assume you know how to do this otherwise go to a garage.
Watch some of the discount brake shops I had a customer who went to save $60 and come out with a $1100 more than I quoted her. This was 15 years ago.

[rw1644h]

Thanks for the reply.
I've bled many brake systems over the years but never replaced a master cylinder. Is the removal/re-install of the master cylinder itself a complex job?
Are all the fasteners,etc accessible from under the hood or will I need to get at it from underneath the dash?

[rhandwor]

If you have power brakes you have two bolts at the vacuum booster and two brake lines to hook up. If you don't have power brakes a rod from the master cylinder connects to the brake arm for the pedal.
Read instructions and bench bleed the master cylinder before installing. Put plastic hoses in the cylinder and push in the back until fluid comes out. Then bleed at the connecting brake lines to the master cylinder. This saves time before you bleed at the wheels.

[manlystanley]

Originally Posted by rw1644h

Thanks for the reply.
I've bled many brake systems over the years but never replaced a master cylinder. Is the removal/re-install of the master cylinder itself a complex job?
Are all the fasteners,etc accessible from under the hood or will I need to get at it from underneath the dash?

I'm not that mechanical and replaced my master cylinder on my 1995 Grand Voyager this past week. Follow rhandwor's procedure and it should go well. One little addition, after I finished the bleeding, I went back to the master cylinder and re-bleed that. I found that apparently the air bubbles had risen up while I was bleeding the tires and got stuck there.

Best Regards,
Stan

[rw1644h]

Thanks for the advice. I think it should be no problem to do this.
I'm wondering where is the fluid leaking to ? I don't see any evidence of a leak. Does this mean the fluid is leaking into the brake booster? If so, do I need to perform any service to the booster?

[rhandwor]

Normally you can see fluid dripping between the brake booster and the master cylinder. Clean the front of any fluid and wipe up spilliage. It is dripping as you drive and brake. I have never found any problem with the booster and have changed many over the years. The fluid in the cylinder bypasses the rubber seals so you don't have positive pressure.
When the booster goes it causes a massive vacuum leak and may shut down the engine.

[rw1644h]

Tanks for your help. I think I'm ready to do the job.