Post by Deleted on Jul 30, 2014 22:08:07 GMT 1
OK it started as an mot issue, but hold on guys before you advise this is the wrong place to post . I tested a Vauxhall Astra G 2001 1.6 SI (spark ignition) the other day and the front brake imbalance was 55%, the rate of increase and decrease clearly not about the same rate, all in all a clear fail no question about it.
I removed the road wheels and removed the sliding calipers but not disconnecting the hydraulics. I don't allow the calipers to hang on the brake hoses once removed from the wheel hubs. . I removed the brake pads which had a good 5mm thick lining material left at their lowest point. I didn't find any brake pads seized when removing, nor did I experience any problems when using the brake wind back tool to push back in the brake caliper pistons, however I did notice that the nearside front brake pads anti-damping spring was missing at the time of removal of the pads.
I measured the brake discs thicknesses at their lowest points and found them to be below the manufacturer minimum 21mm, so I ordered new brake discs and pads and cleaned everything up and re-assembled . I road tested the car for about five miles and can't say I noticed anything wrong, then I put the car in the mot bay and set the headlamp alignment, still not noticing anything wrong. I reversed the car into the rollers and then checked the front brakes, the nearside front brake was binding recording a reading of 40Kgf, the brakes imbalance was about 30%. The rate of increase and decrease at this time was within the maximum 30% range.
I took the car back home (because the job is a foreigner) and at that point I could smell the nearside front brake was operating too hot. I let the brakes cool down and then removed the road wheel to see what was wrong?
I found nothing obvious, so I removed the brake pads and a visual inspection of the outer brake disc face shows that the outer pad is overheating, and seemed to be operating misaligned. The pads and discs are brand new German manufacturer (can't remember the name without looking back at the box sent in) and so now I am really suspecting that a misalignment issue is causing this problem. Further road testing and using an infra red temperature measuring device (yes I know not the most accurate) but is able to show me that their is a good 20 to 30 degrees increase in working temperature of the nearside front brake.
The fitment of the brake pads and caliper did not present any issues during fitting and so I did not suspect a misalignment issue, but quite obviously there is as the disc is changing colour with the heat generated. When the road wheel is jacked up there is no brake bind present when the road wheel to turned by hand, which was very confusing?
Any thoughts on this guys?
I removed the road wheels and removed the sliding calipers but not disconnecting the hydraulics. I don't allow the calipers to hang on the brake hoses once removed from the wheel hubs. . I removed the brake pads which had a good 5mm thick lining material left at their lowest point. I didn't find any brake pads seized when removing, nor did I experience any problems when using the brake wind back tool to push back in the brake caliper pistons, however I did notice that the nearside front brake pads anti-damping spring was missing at the time of removal of the pads.
I measured the brake discs thicknesses at their lowest points and found them to be below the manufacturer minimum 21mm, so I ordered new brake discs and pads and cleaned everything up and re-assembled . I road tested the car for about five miles and can't say I noticed anything wrong, then I put the car in the mot bay and set the headlamp alignment, still not noticing anything wrong. I reversed the car into the rollers and then checked the front brakes, the nearside front brake was binding recording a reading of 40Kgf, the brakes imbalance was about 30%. The rate of increase and decrease at this time was within the maximum 30% range.
I took the car back home (because the job is a foreigner) and at that point I could smell the nearside front brake was operating too hot. I let the brakes cool down and then removed the road wheel to see what was wrong?
I found nothing obvious, so I removed the brake pads and a visual inspection of the outer brake disc face shows that the outer pad is overheating, and seemed to be operating misaligned. The pads and discs are brand new German manufacturer (can't remember the name without looking back at the box sent in) and so now I am really suspecting that a misalignment issue is causing this problem. Further road testing and using an infra red temperature measuring device (yes I know not the most accurate) but is able to show me that their is a good 20 to 30 degrees increase in working temperature of the nearside front brake.
The fitment of the brake pads and caliper did not present any issues during fitting and so I did not suspect a misalignment issue, but quite obviously there is as the disc is changing colour with the heat generated. When the road wheel is jacked up there is no brake bind present when the road wheel to turned by hand, which was very confusing?
Any thoughts on this guys?