Brakes!!!!im stumpted!!

[lowsexplorer93]

Ok. So I have a 1993 ford explorer. 4 wheel drive. 4.0 v6. My wife was driving and the brakes went out. Ya, O SH*T! We got it home and I started working. Looked for leaks. NONE. Looked and master cylinder. Went ahead and changed it. Brand new for like 35 bucks. Bleed the brakes, done. But my brake pettel still goes to the floor. Then comes back up really slow. ARRRG!! what am I missing here. Could it be the abs went bad on me? Help! I have no brakes and Im out of ideas.

 

[Jason]

ABS shouldn't affect hydraulic pressure without the ABS activated. Did you properly bench bleed the new master? If not there is a start. Master cylinders tend to leak out of the piston seal and in to the booster so it's not odd to see no fluid leaks anywhere when they go bad.

 

[lowsexplorer93]

I did bench bleed the new master. Using the vancum bleeder tool that I have.

 

[kevinsranger]

I did bench bleed the new master. Using the vancum bleeder tool that I have.

i'm having a very similar problem, replaced rotted rear brake line, bleed my brakes, nice firm pedal, and as soon as i start the engine, the pedal goes to the floor, so i replaced the brake booster, and master cylinder, and still same symptoms, i have replaced everything, rear brake line, wheel cylinders, bypassed the rabs valve, hopefully this gets resolved because i'm sick of not having back brakes lol

 

[lowsexplorer93]

Yep. Brakes are a must in all my cars. I've never had a brake issue like this before. Hopefully some one out there has had this problem and were able to fix it.

 

[kevinsranger]

Yep. Brakes are a must in all my cars. I've never had a brake issue like this before. Hopefully some one out there has had this problem and were able to fix it.

are your rear drums adjusted? thats the only thing i am wondering about with mine, but havent had time to check, i'm thinking the rear drums may be too loose, and pushing the wheel cylinder piston too far out, but doesnt explain why i get a firm pedal before starting the truck

 

[Shran]

I would check all your rubber brake lines, if they're rotted out they sometimes won't leak but will expand when pressure is applied. Not really likely but something to check anyway.

Other than that, it sounds like you still have air in the master cylinder, or it is leaking internally.

 

[larrybjr]

I would have to agree with the possibility of air being in the master cylinder. Most of the returns we get back at my store are master cylinders that havent been properly bench bled. Im not saying that is the case with yours and Im not applying you didnt bleed the master cylinder correctly but it is a possibility. The brake hoses were my problem when I had this issue on my last bronco ii. My dad and I did the whole system except the brake hoses and thats what it was. I wish you luck I know its a pain.

 

[4.0B2]

my parents owned an explorer for about 5 years and one day we started thinking, we never put back brakes on it. took the drums off, they looked new. started looking around and figured out that switch on the rear that lets the truck know when its nosediving for the abs was bad.. all we did was tie it up and the brakes work amazing.. awesome petal. i'll try to get you some more info on it if you need it. the only downfall is the fact that you really don't have abs anymore, but brakes work great

 

[birddog321]

Check all the Brake line connections. I had te same prob with my b2. I found a connection that was full of mud. Ended up disconnecting everything, cleaning it all and blowing it out w/ a air compressor. Once it was back together and bleed everything worked like a champ