Well this sucks!

[Jspafford]

I called around to find someone to bleed the brakes for be. We are getting 4" of snow tomorrow and I don't have time or manpower to do it before then.

The only place I found was a Ford Dealer.

Took it in and told them what I wante done. They just called and said that there was no air in the lines?? How could they tell without bleeding them? And that I needed a new master cylinder and brake line on one side and caliper slide pins.

WTF.

What are the symptoms of a failed master cylinder?

 

[BlackBII]

For Dealer=Rip Off

Failed master cylinder=No brakes

 

[Jspafford]

The pedal has been spongy for a while now, but yesterday I had the rotors turned and put it all back together. I had to compress one of the calipers and now the pedal will go to the floor if I push real hard.

Seems to me there is just air in the lines. I asked them to bleed it, I don't think they even did that and I am still out the $62 bucks I was supposed to be paying for them to bleed my system.

I am pissed! I am going to tell them I will never bring my cars back to them.

 

[Jspafford]

They said the seals in the master cylinder were shot? Can they be rebuilt?

 

[MAKG]

Rebuilding a master cylinder is seldom worth it without a reamer and oversize piston. Replacing the seals is not a rebuild.... and by the time you buy parts, you might as well buy a master cylinder. Not very expensive, frankly.

Air in the lines is possible -- one (unreliable) way to tell the difference is to push the pedal to the floor and see if it STAYS there. Compressed air is elastic -- it will spring back.

Why do you think they didn't bleed it? That's how you tell there is or isn't air in the system.

Also, just to check, did the master ever run dry during the replacement? If it did, did you bench-bleed it? It's not possible to bleed the master with it installed, but that isn't normally necessary for a caliper or wheel cylinder replacement.

 

[Jspafford]

All I did yesterday was have the rotors turned. I had to compress the pass side caliper to get it back together. Now my pedal is more spongy... It has not been firm in quite some time, but now it is to the point where I would be leary of making a panic stop.

I just assumed there was air or moisture in the lines because the fluid has not been changed in a number of years.

I assume they didn't bleed it because he calls and says I need a master cylinder, brake line, etc... Oh and by the way did you do any rear brake work because if not we don't plan on taking the rear tires off.

Why would a dealer try and bleed the system with the tires on? When they have the lift to get it up in the air and be able to do it so much easier with the tires removed.

They also did not charge me when I picked it up, which I am VERY thankful for, but if they had spent the time to bleed the system and use brake fluid they would have billed me something.

Mike, do you mean hold it to the floor and see if it tries to push my foot back up? Or just push it down there and let it go to see if it comes back up.

The pedal definatly comes back up to normal positing as I am still driving the truck and definatly able to stop even from freeway speeds. I just don't have the pressure I should in the pedal.

 

[MAKG]

OK, if you didn't remove calipers, there is NO way for air to GET in the system without a leak. I thought you replaced a caliper.

So, SOMEthing has to be hosed. You will not get air in the system by compressing a caliper (though you might make the reservoir overflow). You might get air in the system if you tried to bleed it yourself incorrectly.

If there are no external leaks and the fluid is not low, it really has to be the master.

FYI, you can turn the bleed screws with the tires on on the lift. They are in back. But what you can't do is inspect the brakes. I'd suspect they were afraid they would find hosed rear brakes and you'd call BS, which you did anyway.

 

[Jspafford]

So how do I change the master cylinder? Suction out the fluid, undo the two brake likes and electrical connector and remove the two bolts? Do I have to disconnect anything on the pedal? I notice most do not come with a plunger. Does this stay on the booster and then I slide the new one over it?

Thanks!

 

[MAKG]

The actuator is part of the power brake booster and only sits against the end of the cylinder. Check your booster for leaks -- sometimes brake fluid leaks into them and blows them. Easiest is to idle the vehicle and squeeze the booster vacuum hose with a pliers and then release -- if it affects idle, it's blown.

I wouldn't bother sucking out the fluid. Get the right size flare nut wrench (NOT an open end wrench!) or even better, a flare nut crow's foot, cut the top off a small plastic container like an oil bottle, and crack the fitting open with the container underneath and the cap off.

BENCH BLEED THE MASTER BEFORE INSTALLATION! Instructions will probably come with the master itself, and there are some details in the tech section.

I have yet to change a master. Originals are on all three vehicles (believe it or not). That's the procedure I used for the Prizm's clutch master (aside from it being secured to the pedal with a spring clip). I have changed a number of PB boosters, but it's not necessary to separate the master from the lines for that.

 

[Jspafford]

Ok, ill bite. I bled the brakes and they seemed good until I really pushed the petal and then they went mushy again.

I got the master cylinder. How do I get the resivore off the old one? Looks like it just pushes on, but I don't want to break the old one prying it off.

 

[Jspafford]

Ooook, The saga continues.

I got both brake lines loose from my old master cylinder. For shits and giggles while the line to the front wheels was still attached I put the plastic plug that comes with the new cylinder into the port that goes to the rear wheels.

Fired it up, still spongy pedal.

Left that plug in there, got the line to the front wheels loose and put that plug in, so now both ports are plugged off..

Start truck, hit brakes. Pedal will not even move.. My master cylinder is still good.

That narrowed it down to the front brake system as being the problem. Now what all is involved in that system and what is the most likely culprit?

I am thinking calipers but how can I test them? They don't seem to be leaking. What else would cause the pedal to go to the floor if pushed, and is also only in the front brake system?

I am stumped?

 

[Jspafford]

This is my last post until some one replies but I need to give ALL the details.

So to test out my "front brakes being the culprit" theory I hooked up the rear brakes again (the farthest port to the front of the truck) and put the plug in the port for the front brakes.

STarted the truck, lo and behold the pedal was still very stiff. Then I thought well maybe it's the booster I need to know if the rear brakes are actually holding when the pedal is good and firm.

So I put it in reverse and with one foot on the nice firm brake pedal I let out the clutch slowly. Yep, the rear brakes are holding great and the pedal is SUPER firm, as in moved less than an inch when the front brake port is plugged on the master cylinder.

So that leaves me with brake lines or calipers? Am I missing anything?

 

[MAKG]

No, I agree. Nice bit of detective work.

It could be a swelling flexible line. That wouldn't leak. They live between the coil buckets and calipers. In the absence of a helper to stand on the brake pedal while you look (with goggles in case of failure!), I'd replace them if they look cracked or otherwise bad. You can get stainless ones if you want that will last forever and noticeably stiffen the brakes (BTDT).

And I know we're going in circles, but air in the lines can do that....

Perhaps you can do the same experiment further downstream? Such as, plug the line after the junction (I believe on top of the driver's frame rail near the starter), and then before the flexible lines on both sides, and then at the calipers.

 

[Jspafford]

If I was to want to plug the lines where they come into the caliper, what size pipe thread will I need.

 

[MAKG]

I believe those are straight-threaded. They seal by jamming the flare against a seat.

A dial caliper will do you better than my WAG.