A couple of brake installation questions.

[liquidtiger720]

As many of you know, im not the most mechanically inclined person on earth...so I have a few questions about replacing + bleeding the brakes.


1. When putting "anti-squeal" lube onto the brake pad...where exactly do I put it? The bentley refers to it as the contact points, but does any body have a visual picture they can refer to, to show me?

2. When bleeding the brakes...two people style. Can somebody outline the procedure for me?

TIA

[liquidtiger720]

anybody?

[Kalevera]

Josh, I would use copper paste versus whatever came packaged with the pads. Much better heat resistance over time. Some people use RTV (!). Whatever you use, the stuff goes on the back of the pads, on the points where the backing meets the caliper or piston. So the outside pad should pretty much be swathed up, the piston side pad should have it around the piston. Some pads have antisqueal shims, in which case the shim goes on the pad backing, then any antisqueal compound goes on the shim. Don't let any gunk get on the friction material itself. Brake cleaner will get it off if any gets on.

First step is to remove as much fluid as possible from the reservoir. I syphoned it off before I got access to a mityvac, but a baster will also do the trick. If the reservoir has a lot of gunk in it, might as well pull it off of the grommets and clean it out -- be careful about flying brake fluid, though. Neutralize anything that gets on paint/bodywork as quickly as possible by spraying it with water.

Fill the reservoir with fresh fluid. I usually crack all of the bleeder screws free before actually bleeding the system, because they can get stuck. Yours should be 7mm all the way around, but you may have 11mm on the fronts (I forget -- some M3s use the same calipers, and they're 11mm FWIR). Also, get a length of rubber, preferably clear, tubing to route the fluid from the bleed screw and into a container.

Go to the rear pass side caliper and have the brake pumper (BP) pump up the brakes, open the bleed screw and have the BP continue pumping until new fluid comes out. Be mindful of the fluid level in the reservoir, it can drain quickly. Once new fluid is coming out with no bubbles in it (this is why you need clear tubing), I close the bleed screw mid downward pump (ie - the BP is ~ 1/2 way through a downward stroke). Some say to hold the pedal down and close it, but I've only seen that work for clutch bleeding.

Repeat the bleed procedure for the rear driver, front passenger, and front driver calipers. Be mindful of the fluid level, watch it and top it off as frequently as possible. If the reservoir runs out of fluid, things can get tricky.

best, whit