Brake job gone wrong

[iLLuSi0nS]

I took my car to the mechanic. These guys are friends so they hooked up with all the maintenance I needed. Got new brake pads (front and back), new rotors, new struts, new shocks, new arm bushings, and a few other things that wont relate to my problem.

But anyway, car was braking like never before for the first 2 days, I loved it!!! Then I was driving on the 3rd day and hit a pot hole, and I doubt this is what caused the problem, but my brakes were never the same after that.

Now when I press the brakes, I have to press it in all the way, passed the air cushion, then it finally brakes when the pedal is all the way hitting the ground. The braking strength is still amazing, but I have to press it in ALL the way for it to brake. I took it back to the mechanic and he bled the brakes again. Drove it, it got a little better, but not that much. He told me it is the master cylinder and I need it replaced. He showed me that when I pressed the brakes, the little rubber nipple on the brake fluid tank would pop out and make noise like it was releasing air.

I complained about how it could be a master cylinder, and how all of a sudden when all this work was done on the car that the master cylinder decides to go bad, it cant be a coincidence that this happens right after they did all this work. They took it offensively and now I am stuck with no friend mechanic and don't know what to do, or who to trust. Any advice would be good. Thanks in advance

 

[notrayray]

What year, mileage, engine, tranny, etc.

 

[BTO]

It sounds to me like your mechanic is giving you the straight dope. Listen to them. Don't slam them.

 

[JeremyH]

It sounds to me like your mechanic is giving you the straight dope. Listen to them. Don't slam them.

Agreed. A MC can fail. Let them look into it...

 

[iLLuSi0nS]

Thanks for the reply guys, its a 99 sr5 6cyl 140,000 automatic.

I didnt slam him, I just dont see how a master cylinder can fail RIGHT after a brake job, I am not saying he did anything, I just have a feeling its really not the master cylinder, and even if I replace it, its not going to fix my problem, then I am going to be stuck with another huge bill.

 

[Fireball]

It sounds like he showed you the exact issue when you took it back to them. Why don't you think replacing the MC will fix things?

If you really don't believe those guys take it to a shop and get another opinion. It drove fine for a few days after they fixed it. I don't think there is a way to sabotage a master cylinder so it works perfectly for 2 days then fails. Then again, I've never tried to sabotage a master cylinder...

 

[iLLuSi0nS]

People are taking me the wrong way, including my mechanic. I would never say someone sabotaged me, but what are the chances the "master cylinder" goes out right after a break job. And why did bleeding the breaks make it better. I read around these forums and people are saying sometimes there is a lot of air stuck and you have to bleed them half a dozen times.

 

[Lignum]

but what are the chances the "master cylinder" goes out right after a break job.

Sometimes things happen by coincidence.....

I had a old dodge with a 383ci v8, put a new carb on and suddenly the car didn't have any fuel pressure....it turned out the factory had improperly hardened the fuel pump pushrod and it had been wearing down for the past 30 years.....Totally unrelated story but it goes to show that sometimes things happen by chance...

 

[Asmara]

Cookies or 6 pack as appropriate

Like everybody says, it sounds like your trusted mechanic is giving you good advice. I'd bring him a plate of cookies or 6 pack along with a mea culpa and patch things up.

I have heard of one thing happening with bleeding the brakes that could damage the master cylinder but it wouldn't be the mechanics fault but rather the fault of poor maintenance.

If you use the push the pedal to the floor method to bleed the brakes and the fluid is old, dirty and hasn't been replaced in 100 years, the push rod in the cylinder can develop corrosion/buildup on it on the parts that are not used in everyday driving. When you push the pedal to the floor the seals encounter the seldom used corroded area of the push rod and can be damaged. This site has some info on bleeding brakes and power bleeders and talks about it. I called it a push rod, this site calls it a piston. They're probably using correct terminology.