I have a 1995 F150 4x4 with only 47,000 miles. A few weeks ago the left front steel brake line from the MC down to caliper rusted through. I replaced both that line and the line going across the front to the right side as it was suspect as well. Since then I have put no less than 3 quarts of brake fluid through the system trying to get rid of a soft pedal. I know at one point I may have let the reservoir go dry, but since have thoroughly bled both front and back lines using the typical RR, LR, RF. LF cycle. I bled the ABS valve and even cracked the front line at the MC while under pressure to try to bleed the MC. Am I missing something? I hear an airlike, squishing sound when I push the pedal down while the truck is running. Pedal will seem hard if no boost is applied(truck off). Thanks.

Ray

 

There is still air in the master most likely.

Start with a master bleeding kit. It will have lines that put the fluid right back into the master. You need to do this until no more air is in the return lines. Then reconnect the lines and start bleeding the system as you have been starting rr, lr, rf, lf. You shouldn't need to bleed the ABS valve. Enough fluid will pass through it.

If you can't find where the air is after that, clamp the soft line above the rear axle and clamp both soft lines on the front. While someone is depressing the pedal, release the lines one at a time. When the pedal falls, that is the one with the air in it. Bleed that one and try again. With all lines clamped it should feel like a rock. If not, it is in the hard lines or the master.


The swishing sound is normal, it is vacuum in the booster.

Good luck....I hope this helps...

 

Thanks for the quick reply.

Where would I find a master cylinder kit?

Ray

 

Anywhere that sells master cylinders. Most new cylinders come with them too. I'd try the big boys 1st, like Pep boys, Checker, Champion, Napa, Car quest, etc.....