E39 - K&N Filter

What I would advise is to check to see if you can unscrew the torque or Allen key screw in the hub before disassembling the brake calliper. I didn't, thinking it would be straight forward, (usually is) in this instant it wouldn't budge. One can use WD40 penetrating oil or a Bunsen heat or hot flame. As time was ticking I decided to cut the old plastic lock ties from when I addressed the problem before as a quick resolve and use a fresh plastic lock tie.
On inspection of one of the control arms I noticed the rubber boot was a little flaky to my slight annoyance, as this control arm was replaced a few weeks after I gotthe car. The tie had obviously rubbed onto it after a period of time and damaged it. I don't think the rubber had split and I am hoping the BM will get through its MOT, we shall see. The problem with the brake dust plate is that the lower hole on the left of the plate was oversized, (Aluminium, erosion) and required an oversized washer to reform the bolt hole and overlap the eroded metal. The bolt was also missing so also required a bolt. I hadn’t got a bolt of the correct size. So it just left a conspicuous repair using another tie threaded through the plate and away from the rubber boot on the control arm. This was completed successfully and was much better than the first attempt but only as a short term temporary repair. Check for rotor clearance, (no scraping noises), calliper, wheel, refitted, brake pedal depressed a number of times and job done, for now. It feels like two paces forward and two paces backwards on today’s exercise. However, one is aware of what needs to be done and mentally register it; the problem is in the remembering. Be warned probe, and those with experience, you will have days like this.

                        The size of the washer depend
                        on the amount of metal missing
                      from the plate through erosion and
                     how flat the surface is. Not all
                 plates have indentations as illustrated. The washer needs to be just larger than the eroded area, this will be the new bolt hole. This is an acceptable repair as long as the plate does not deteriorate further.

Note: The vehicle does not need brake pad dust shields to operate and a good ventilation can help with braking, Some owners have removed them, however they are advisable for preventing debris like dust and small stones from damaging rotors and brake pads.
By using a locktie, for a short term repair is acceptable, be careful not to allow ties to come into contact with rubber boots etc.