Master Cylinder Push Rod

WARNING: This page is about a different car, the 2002 Mazda 626. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Push rod has an adjustment screw to maintain correct distance between booster push rod and master cylinder piston. If push rod is adjusted too long, it prevents master cylinder piston from completely releasing hydraulic pressure, causing brakes to drag. If push rod is adjusted too short, it causes excessive pedal travel and an undesirable clunk in booster area. To determine which of the following adjustment procedures to use see MASTER CYLINDER INSTALLATION NOTE under MASTER CYLINDER under REMOVAL & INSTALLATION.

Adjustment Clearance At "C"

Measure and record height "D1" of the Adjustment Gauge (49-B043-001). See Fig 1 .
Turn the adjusting nut until the adjustment gauge body sets squarely on the master cylinder. Turn only enough for the body to touch.
Measure and record height "D2" of the adjustment gauge rod. See Fig 2 .
Subtract "D1" from "D2". Turn the nut to shorten the power booster push rod an amount equal to the difference. See Fig 3 .

Clearance At "B"

Push lightly on the end of the Adjustment Gauge (49-B043-001), and measure the clearance between the adjusting nut and the adjustment gauge body, clearance "B". See Fig 4 .
Turn the nut to lengthen the power booster push rod an amount equal to the sum of the clearance measured at "B". See Fig 3 .

Fig 1: Adjusting Push Rod Clearance "C" (1 Of 2)

Courtesy of MAZDA MOTORS CORP.

Fig 2: Adjusting Push Rod Clearance "C" (2 Of 2)

Courtesy of MAZDA MOTORS CORP.

Fig 3: Adjusting Master Cylinder Push Rod

Courtesy of MAZDA MOTORS CORP.

Fig 4: Adjusting Push Rod Clearance "B"

Courtesy of MAZDA MOTORS CORP.