Manager Forum

I have a customer with a 1989 Probe GT (aka Mazda MX6). After doing a complete brake job I bled the system. The next day the pedal went to the floor. I repeated the Bleed procedure several times with the same result. I had the system bled with a pressure bleeder and they were fine for a week, then the same old problem, pedal went to floor. I was present when the other shop bled the system and we all checked for a possible leak. We all determined there was no hydraulic leak anywhere in the brake system.

Does anyone know if there is some specific way to bleed these brakes that will get all the air out and not cause the pedal to soften after sitting overnight?

We have put two new master cylinders on it!

Thanks ahead for any help,
Joe Gallagher
joetngallagher@aol.com
Nashville, TN

I would say the master cylinder is bad. I guess you would have to plug the ports at the cylinder and see if it still loses pressure.

We have put two NEW master cylinders on it

Confirmation that I hate Ford Probes. Nothing but trouble!!! Good Luck! Remember to post fix.

I would drive till the peddle goes low and then block off all 4 brake hoses and have a helper press on brakes while removing clamps one at a time and see which one causes trhe most drop in peddle. I have had calipers that would get air in them and not leak fluid. Hope you figure this one out and let us all know.

I would block off the lines and check. I have never had any issues bleeding these. Just because a part is new doesnt make it good.

Does it have anti-lock? I remember having to use a tool that pluged into the controller and it would activate the pump. Next step was cycle each valve while bleeding each wheel. It was a Rotunda tool that I had to use 3 or 4 times and did not like it but it worked.

I think it was on a T-bird or Crown Vic, no direct experience with Probes.

The bleeding seq. is RR, LF, LR, RF

I have had rear calipers on those cause me this type of problem. What I do to isolate the problem area is have someone sit in the car and pump up the pedal and then using needle nose vise grips......this is important..adjust them so they don't crush the hose.....pinch the hose shut at each wheel. then the person in the car can release the pressure. now if he hits the pedal agian and it has a good pedal then the problem is at the wheels if it is bad it is higher up (Master cylinder or prop valve or ABS). If it is at the wheel have him hold pressure and release the vise grips one at a time till the pedal drops and you will find the culprit. Just be careful not to damage the brake hoses.

does it have abs?. if air got into abs driver that may be your problem. the only way that i know of for getting the air out is using a ford scanner to activate abs system while bleeding. in rare occasions i've had air getting into the system through the the seals beng installed improperly on the caliper piston. i've also seen brake fluid bil in the caliper and even after t cooled down a little amount of air remained. if this were the case you'de see the rotors turning a blue color. where is the air appearing? when it's pressure bled is it only coming out of the rear? one caliper?. never assume that the parts originally replaced are functioning properly. good luck.

SO Whats Going on Is it Fixed?

SHIPPED CAR TO DEALER. CUSTOMER RETURNED TO ME AND SHOWED ME AN INVOICE FOR $1355. STILL NOT FIXED. HE'S GETTING A LAWYER