Hi i have a question so i have a 1997 Ford F-250 5.4l i replaced all brake lines master cylinder and brakes and when i turn the truck on my brakes go the floor any answers for me plzz help me
Oh boy .. I had the same problem on a money kit car.
It was due to air in the master cylinder or lines .
Did you pump your brakes and bleed then?
@klob
its my bfs truck im helping him out tbh but if u want him to explain better ill have him explain
Did you bench bleed the master cylinder? That's usually necessary to get all the air out.
@chucktobias
he did
It sure sounds like there is still air in that brake system. How was it bled? Pressure bleeder? Gravity bleed? Suction bleed? Old-school pumping the pedal? A ballooning brake hose will cause a soft pedal but I wouldn't expect it to go to the floor unless the hose actually burst. Another possibility is defective master cylinder. All too many aftermarket parts these days are of low quality. Does it have ABS? Some ABS systems require a specific bleeding procedure.
@chucktobias
it does just this truck is a rare one tbh
we did the old fashion way
he did 3 times
if bleeding it he was driving home and he said all brakes to the floor he replaced everything
I would definitely check into the correct bleeding procedure, some ABS systems (especially older ones) are particular about how they're bled. If after following the factory-recommended procedure you still have a problem it may be time to start thinking about whether the replacement master cylinder or possibly some ABS components are bad. (On some of those old ABS setups the brakes do not work normally if the ABS fails.)
@chucktobias
abs doesnt work
@chucktobias
abs doesnt work
I'm not familiar with that ABS setup but it might be worth checking out what the symptoms of ABS failure are on that vehicle. Those systems can throw a real curve ball at you when analyzing brake problems. Maybe Scotty can chime in if he's worked on one of those?
@chucktobias
Ok
The brakes should be GRAVITY bled on all vehicles with an ABS system BEFORE you pump the brakes. This is to prevent you from destroying the ABS module (which is rare but can happen). Gravity bleed the brakes and report back.
@inthedetails
he did
@inthedetails
All I can think of at this point - assuming that the brakes really have been thoroughly and properly bled - is that either the new master cylinder is defective and leaking internally, or it's a side effect of the ABS system malfunctioning.
@inthedetails
we fixed abs went out but he doesnt have to have it