Brake Caliper - Rattling Sound
NO.: 907GROUP: 51
SECTION: 5
DATE: February 1994
RE:
Front brake caliper (guide pins) Girling (Lucas) two-piston type
700, 1983-91
REFERENCE:
TP30838/2; 11/93, BRAKES
TP31087/2; 10/93, BRAKES 700/900 SERIES
Rattling sound from Girling (Lucas) two-piston front brake caliper
Excessive play between the caliper guide pins and their bores, due to wear, might in some cases cause a rattling sound. This does not affect normal braking function of the vehicle. A repair kit, P/N 271854-2, containing guide pins with integral bushings, rubber dust seals and mounting bolts for both front wheels, has been produced to correct this condition.
Procedure for replacing guide pins:
A1
Separate piston housing from caliper retainer (remove bolts A). Use 17 mm wrench to hold guide pins while removing bolts.
Tie up piston housing with wire to avoid damaging brake hose.
Remove original guide pins (B) and dust seals (C).
A2
With a brake cleaning solvent, clean guide pin bores (with a cylindrical wire brush) and clean the dust seal seats in caliper retainer.
A3
Grease dust seal seats and guide pin bores with silicon grease, P/N 1161325-4 (clean and use one of original pins to lubricate bores before discarding pin.)
A4
Apply thin coating of silicon grease. P/N 1161325-4, to new guide pins (and to rubber bushings).
A5
Fit dust seals to guide pins.
A6
Insert guide pins in correct position in caliper retainer (see below).
Note
guide pin positions differ on left and right-hand sides.
Left-hand side: Yellow guide pin in lower position.
Black guide pin in upper position.
Right-hand side: Yellow guide pin in upper position.
Black guide pin in lower position.
A7
Check that dust seals are correctly installed by pressing guide pins from outermost position permitted by seals to innermost (bottom) position.
Carefully press in brake pistons a couple of mm with adjustable pliers, ensuring that piston dust seals are positioned inside piston ends.
Check that brake pads are free to move in caliper retainer. Clean pad seats if pads tend to stick (if necessary).
Apply silicon grease, P/N 1161325-4 to edges of brake pad backing plates where they contact pad seats.
Reassemble brake caliper and caliper retainer. Use 17 mm wrench to hold guide pins and use new bolts (from kit) and torque to 34 N-m (25 ft.lbs.).
Operation No. Labor Description Time Allowance
511773 Guide pins, front brake caliper, 0.1 hr
both sides, replace (with brake pads removed)