Most times Brakes..Some times no.

1997 Mercury Mountaineer, Most times Brakes OK... some times to the floor... Here the Skinny, 98% of the time Brakes function normaly, no pulling good foot preasure, then for no reason you go to use the brakes an your foot goes nearly to the floor , one pump and your back to normal. This condition exists Hot or Cold, Wet or Dry ... I have taken the following actions, checked wear on all pads, 75% + on all 4 Blead the brakes... all 4 the fluid looked clean when I started ...looks a little cleaner now :-) no leaks, hear no Vacume leaks.. all 4 calipers actuate freely. ... I changed the Pads about a year ago... I did not remove the bleeder screw as it was suggested in some of the Posts that I searched, I would have thought tho if my problem were related to bad fluid in the ABS sstem it would have shown up long before now. any way kinda thumped on this one... Things I have concidered but have since ruled out: Air in the lines... Lost Caliper Pin Cracked or Broken Brake pad Contaminated Brake Fluid Leaking Calipers

Hoping one of the followers of this forum will have a clue as I no longer have one... :-(

Reply to
Frankenstien
Loading thread data ...

I've seen loose wheel bearings do this (though yours should be the sealed assemblies). Drive in a straight line and all is wheel.... take a couple of turn exhuberantly without touching the brakes and the pistons get knocked back in the calipers... It's a long shot but worth a look...

Is this RABS or 4WABS?

Reply to
Jim Warman
97 should have ABS on all four

----- Original Message ----- From: "Jim Warman"

Reply to
Happy Traveler

Could be an internal leak within the master cylinder. You would think that it would do it every time if this were the case, but I have seen well worn master cylinders do this intermittently. The fix would be to have the master cylinder re-built or buy a rebuilt unit or a new unit.

Reply to
sf/gf
4WABS .... Had it suggested to me the Master Cylinder, Not sure if thats it, but seeing as how I'm running out of options, this may be the way to go.
Reply to
Frankenstien

I have had this happen on a brand new '96 Explorer with less than

3,000 miles. Kinda of scary when applying the brakes and having the pedal go practically to the floor. Anyway back to the dealer, they replaced the master cylinder.

This is not a safe condtition, get it fixed ASAP

Reply to
Fred 2

Amen, Brother!

-Paul

Reply to
carbide

And to think I just bought new Sneakers..... (I have 3 other Vehics... so this one stays parked till fix time)

Reply to
Frankenstien

Thought I'd give an update...Turns out once upon a time ago the previous owner..or Ford had replaced the Brake lines... this person installed the right line on the left and the left line on the right, this would stretch the line while turning, this "stretch would increase the volume of fluid required to actuate the brakes, thus giving the "sometimes brakes.. sometimes not".

Reply to
Frankenstien

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.