bleeding the brakes

[mtrExplorer]

have a question for ya brake guys. long story short, i ended up doing all 4 wheels, new rotors and pads. i figured while im at it i would bleed all 4 calipers, after bleeding the brakes ,they work good, but if i keep my foot on the brake pedal long enough it will go to the floor.
is this a sign of incorrect bleeding or possible master cylinder going bad??
like i said the brakes work fine, just not sure bout why the pedal goes down to the floor if i keep my foot on the brake pedal long enough.

 

[Tech By Trade]

If you bled the brakes correctly you have a bad master cylinder.

 

[mtrExplorer]

is that a hard fix?
is there any way for sure to know if the master cylinder is bad?
im sure i bleed the brakes correctly
brake pedal down -open bleeder till i saw fluid come out then close bleeder- then let foot off brake. repeat this process 3 or 4 times each caliper.
this is correct way right

 

[Tech By Trade]

Use a one man brake bleeder system, I got mine at princess auto, in the US Harbor Freight. If you don't have that it takes two people. One person pressing on the brakes and one to open the valve and close it. If you let off the brake with the valve open it sucks air back in.

fill the reservoir. Person in the car presses the brake. Crack the valve until just before the break hits the floor. tighten the valve. let your foot off the brake. Check the reservoir. Fill if required. repeat until no air comes out of the valve.

The one man kit has a little bottle that allows the air past, and sucks fluid from the bottle when the vacuum is present, so it doesn't suck air back into the line.

Master calendar is easy, just replace it and bleed the lines again.

 

[mtrExplorer]

ok. thanks for the pointers' thats how i did the bleeding on all 4 yesterday.
had a buddy press the brake pedal down then i open the bleeder and closed it,
i waited till the pedal hit the floor then closed it . should i of closed it before the pedal hit the floor?
is there anyway to tell for sure if the master cylinder is bad?
cause the brakes work fine ,its just that if i put enough pressure down on the brake pedal it will go down to the floor

 

[Tech By Trade]

It shouldn't go all the way to the floor, and if it starts creeping when its on the floor you have issues. Its not to bad to change.