Saturday Project - How to Inspect Your Brakes

Routine brake system inspection and fluid service can help extend the life of your brake system and ensure your brake system is safe and functioning as it should.

Inspect your brakes once a year, or when noticing any changes in the brake system, ie. poor stopping, soft brake pedal, or excessive noises.

Locate brake system reservoir. Check for level and clarity of brake fluid. Brake fluid should be changed when two years old or dark brown.

It is critical to protect the car's paint. Brake fluid is corrosive to paint, and it's an easy step to prevent damage.

Remove brake cap and filter, siphon out almost all brake fluid, and then refill with new fluid (if fluid is bad and needs changing).

Visually inspect the rotors for excessive or uneven wear, heavy grooves, and hairline cracks. Then, you'll need to check the thickness of the rotors. If you're a handyman, you might have a micrometer or a industry standard brake thickness gauge, which you can purchase. Compare the measurements to the recommended brake disk thickness spec range.

Disk is in average acceptable condition.

We used a micrometer to get a readout of the thickness and compared it to the other side, as well as to the manufacturer recomendations.

Second, you want to check your brake lines. Checking rubber lines is critical on older vehicles due to age and exposure. Sometimes hoses visually look good on the outside, while deteriorating on the inside. You can usually diagnose this by squeezing the lines to feel flexibility and visually expose cracks. Also make sure all hoses are dry. Any moisture could be brake fluid.

Gently flex the hose and move it around, looking for stress and cracks.

Pay special attention near the fittings. This is where separations and wear can build up.

Don't forget that the rear wheels have hoses, sometimes more inboard.

Inspect the brake pads for consistent wear and pad depth. Some pads have a line. As a general rule, if it looks thin, it probably is thin. While the pads are out, inspect brake caliper dust covers, looking for tears, cracks, and or fluid leaking.

There are different caliper brakes for different cars. Yours may not look like this.

Some break pads have wear indicator lines or grooves. If wear passes these marks, you'll need new pads.

Brake caliper dust boot. These are good and dry for as old and original as the car is.

On some older cars with drum brakes, inspect dust boots at the brake cylinder. Look for leaks and excessive damage or rust. Check brake pad thickness and excessive wear on the drum. Always refer to manufacturer specs.

After removing the brake drum, visually inspect.

Visually inspecting boots at the cylinder.

Checking brake pad thickness. use rivets to check depth.

Next, to flush the brake fluid out of the system, we have a couple of recommendations. For older cars, we recommend gravity bleeding, seen in the photo below. Hover over images for more detailed instruction.

Attach a line from the bleeder nipple to a container of your choice. Open bleeder valve enough to drain fluid.

Vacuums are another possible way to bleed the system, but can stress older master cylinder parts.

Gravity bleeding is a slow process. When looks clear, tighten the bleeder valve on the caliper.

How To, SortMike ButlerDIY Brake Inspection, How To, Brake Inspection, Brakes, BMW 320i, TwoComment