ABS for Early Subaru Part 4:

Air Bleeding Overview:

The air bleeding procedure for the ABS-2E system is similar to that used for other systems, with a few added steps. Refer to the Service Manual for general rules and step-by-step instructions. As always, pay attention to the basics. Before you begin, make certain there are no leaks in the system. Then bleed the secondary chamber of the master cylinder first and the primary chamber second. To accomplish this, work in the following order:

1. Right front brake
2. Left front brake
3. Left rear brake
4. Right rear brake

Pedal Travel Measurement:

To properly perform the following procedure, you will need a pedal effort gauge (SOA 636500). With all four brake circuits bled, check pedal travel as follows:

• Put the wheel in a convenient position.
• With the engine idling, use the pedal effort gauge to apply 110 pounds of load to the brake pedal.
• Measure the distance between the brake pedal and the rim of the steering wheel.
• Release the brake pedal and take the same measurement.

Tip: Tie one end of a length of string to the brake pedal. Press the brake pedal, and at the opposite end of the string, place a paper clip to mark the first distance. Then release the brake pedal and place a second paper clip to mark the second distance. Measure between the two paper clips with a ruler or tape measure.

• Bleed the secondary chamber first.
• Pedal effort gauge measures force.