Sorry, but I couldn't resist the pun... despite it being done to death...
Anyway, I've put this in general as it is car related, not nothing to do with my Fazers
So, I have just finished the task of replacing the discs and pads on all 4 corners. The rears were very low and almost at metal on metal and the fronts were just old and figured I'd do the whole lot anyway. Having completed the procedure, I bled all 4 corners a few times and the pedal became rock hard - much better than ever before (woohoo I thought)...
But ahah, not so fast the car says, upon starting the engine, the brake pedal falls almost to the floor and the brakes become absolutely useless...
I've never experienced this before and I've actually done the brakes on the same make and model car before as well!
So, off I trot to the internet to do some research... to which I find 101 various answers and counter-arguments, the highlights of which are;
1) Air is still in the system.
2) Calipers / Master Cylinder / Booster are busted
3) ABS system needs to be bled
4) Seals in Master Cylinder have flipped
For each of these things, there is a counter-argument that people have made and so far, in not a single thread I've read has the OP come back with the solution to their woes... fucking bastards...
Now, I could go all night attempting to bleed the brakes, but that seems to have been done by several people with no success. I can't see any bulging on any of the flexi-hoses and there are no leaks on any of the calipers as far as I can tell. I then came across a guide to test the booster, so followed its instructions;
32. Brake Booster Test
Functional Test:
1. With engine off, depress brake pedal several times; then, depress the pedal hard and hold that pressure for 15 seconds. If the pedal sinks, the master cylinder, brake line, or brake caliper is bad.
2. Start engine with pedal depressed. If the pedal sinks slightly, the vacuum booster is working. If the pedal height does not vary, the booster or check valve is faulty.
Leak Test:
1. Depress the brake pedal with the engine running, then stop the engine. If the pedal height does not vary, while depressed for 30 seconds, the vacuum booster is fine. If the pedal rises, the booster is faulty.
2. With the engine off, depress the brake pedal several times using normal pressure. When the pedal is first depressed, it should be low. On consecutive applications, pedal height should gradually rise. If the pedal position does not vary, check the booster check valve.
My car responded as expected, suggesting that the booster is in full working order.
So, minions of FOC-U, have any of you in your travels experienced said problem and actually managed to solve it? My only real next step is to test each caliper by clamping the flexi-hose (and trying not to destroy it in the process) and spend the next year bleeding the brakes with gallons of DOT4 until the problem magically fixes itself...