1.8 TDCI brakes problem

Dia1988

Hi all,

I changed brake pads on tbe front and rear on a 1.8 TDCI 2008 Ford Focus, with discs front and rear about 6 weeks ago.

The front brake pads were changed first and I test drove it for a day and was fine braking, then changed rear brake pads with the help of a friend.

The passenger rear pads were difficult to remove/fit as the cylinder had to be re-wound and the bleed nipples were quite rusty but didn't seem to be leaking.

Anyway, new brake pads were fitted and system bled, but the brake pedal would only hold pressure for a while and then go to the floor.

To brake effectively, you would need to pump the brakes 2 or 3 times as the "hard" brake pedal would only hold for a few seconds.

The Focus has now done about 5 to 600 mikes and looking at all 4 discs, the only brake pad that isn't making contact with the brake pad is the rear passenger one, as it has surface rust unlike the shiny discs of tbe other three discs.

Plus, the brake fluid resevoir is now low when it was full when brakes were replaced.

Could this only be tbe bleed nipple needing a replacement or isit the cylinder that needs to be replaced? Ive not had a chance to check the bleed nipple.

Any info is appeeciated,

9935452

is there any sign of brake fluid leaking??
if not you still have air in your system.
There could be a bleed nipple or two on the master cylinder.
Worst case scenario is air may have gotten into the ABS pump which may be a main dealer job to trigger the pump on the computer.
I have been told you can trigger the pump by standing on the brakes causing the wheels to lock up and the ABS kicks in.

dr.fuzzenstein

Best thing to do is to re-check everything, just take off all the wheels one by one and check the caliper and the pads, make sure everything is back together as it should be, check for leaks, check the rubber seals and the pistons for leaks.
I once managed to dislodge a rubber seal between piston and caliper on my GF's MX5, it was immediately obvious on the test drive (turned round after 50 meters), pedal would sink to floor and had to be pumped.
If any calipers are leaking check and re-seat all seals. You may have to go as far as taking the suspect caliper off and disassemble it on a bench.
If seals and pistons are perished and corroded, get a rebuild kit.
If there are no obvious signs of anything wrong, re-bleed the system, I'd say do that in any case. How did you bleed the brakes? I tried using a vacuum pump once (CMax), but it takes a fair bit of vacuum to properly bleed those brakes, you may be better off with a mate and the "up-open-down-close-up" method.
I know it's a pain, but you can't take chances with your brakes.
But really check to make sure there are no assembly errors, those would be the most common.
Take some pics and post them here if you're not sure. We're always willing to help, especially people who know how to spell brakes!

martinr5232

Sounds like a faulty calliper. Do you have any leaks on the side that the disc is rusty ??

Did you wind back in the pistons and pump the footbrake before pulling the handbrake ??

mullingar

+1, seized caliper.

Also, brake fluid just doesn't disappear, you have a leak somewhere.

dr.fuzzenstein

I don't know about seized. 99% of the time when you take something apart and it goes wrong afterwards, its reassembly error.