The MGB handbrake operates the rear drums via a cable mechanism, and a poor handbrake is one of the most common complaints on the car. The cause is almost always a stretched or corroded cable, a seized handbrake lever pivot, or incorrectly adjusted rear brakes, rather than any inherent fault in the mechanism itself. The rear brakes on the MGB are manually adjusted and do not self-adjust, so shoes that are not correctly set will leave the handbrake unable to hold the car regardless of cable condition. Before replacing the cable, always check the rear brake adjustment first, this is the most frequently overlooked step.
Apart from minor improvements to the thumb-button release, the handbrake assembly remained unchanged until 1971. On 1972 and later cars, the handbrake lever was cranked over to the right to clear the new centre console. The same handbrake grip was used throughout the production run.
Handbrake Cables
Eight different cable specifications are used across the production run, spanning changes relating to axle type, wheel type, the 4-synchromesh changeover, and rubber bumper models. The most significant mechanical distinction is between early and late cars, from 1977, at car numbers GHD5-412301 (GT) and GHN5-415001 (roadster), the handbrake activating mechanism was redesigned with rod-type plastic-coated cables with greaseless inner cables and no compensating lever, the purpose being to improve clearance to the fuel tank.
Earlier cars used an entirely flexible cable secured to the rear of the differential cover. In the early years, different cables were used depending on whether the car had a banjo or tubed rear axle, and further differences persisted depending on whether disc or wire wheels were fitted. Handbrake cables are available for banjo axle cars in steel wheel and wire wheel specifications, for tube axle chrome bumper cars in both wheel types, for rubber bumper cars to 1976 in both wheel types, and for September 1977-onwards cars in both wheel types, covering the complete production run. The cable clamp, cable sleeve, locating strap, and handbrake strap are all available for correct routing and retention.
Lever Assembly & Adjustment
The handbrake lever assembly comprises the top lever, bottom lever, and pivot bush, all available individually. A seized pivot bush is a common cause of a handbrake that does not release fully, applying the brake pulls the cable, but corrosion in the pivot prevents the lever from returning under spring tension, leaving the rear shoes partially applied. This produces a dragging sensation at the rear, premature shoe wear, and heat build-up in the drums. The pivot bush should be inspected and lubricated during any rear brake service.
The handbrake adjuster barrel and nut allow cable tension to be correctly set after replacement. The cable should be adjusted with the rear brakes properly set first, tighten the adjuster until the handbrake holds the car securely within three to four clicks of lever travel, then verify that both rear wheels spin freely with the handbrake fully released. The handbrake spring, fulcrum pin, anti-rattle washers, clevis pin, and all associated fixings are available throughout.