MG Magnette ZA and ZB (1953 to 1958)

The Z-series Magnette was the first MG built as a monocoque, using the BMC B-series engine. Designed by Gerald Palmer, who had earlier worked on the Jowett Javelin, it was developed alongside the Wolseley 4/44 as the sportier of the two, with twin carburettors and rack and pinion steering. It was shown at the 1953 Motor Show, with deliveries from early 1954, and the improved ZB followed in 1956. Production ended in late 1958, and the car was replaced by the Farina-styled Magnette.

The ZA and ZB are handsome, well-proportioned saloons with leather seats, a wood dashboard and a driving position that feels more sports car than family car. The steering is precise and the handling tidy for the period, though first gear is very low and the car is tall-geared on the open road. Today the Magnette is admired as one of the best-looking British saloons of the 1950s, with sound mechanicals and strong club support. The challenge is a body full of natural rust traps and scarce brightwork, so condition matters far more than which version you choose.

• Years: announced October 1953, first deliveries March 1954, production to late 1958 with the last cars sold in early 1959.
• Body style: four-door saloon only. Varitone two-tone versions on the ZB.
• Engine: 1489cc B-series four with twin SU carburettors. ZA about 60bhp; ZB about 68bhp at 5,400rpm after the 1956 changes (higher compression, larger SU carburettors, revised exhaust manifold).
• Gearbox: four-speed manual with synchromesh on second, third and top only. A clutchless Manumatic option was offered on ZB and Varitone models; Classics World says 497 were made.
• Suspension and steering: independent front with coil springs, a single lower arm and radius arms, no anti-roll bar originally; live axle on leaf springs at the rear; rack and pinion steering.
• Brakes: hydraulic drums all round, twin leading shoe at the front, unchanged through production. No servo originally.
• Production: about 36,600 in right and left-hand drive, per the MG Car Club and Classics World.

• 1954: ZA deliveries start. The earliest cars lack front quarterlights (added from chassis 751) and have a 4.3:1 axle ratio.
• March 1955: from car 6360 the painted metal dashboard is replaced by real wood.
• July 1956: engine uprated from 60bhp to 68bhp. Auto Express says top speed rose from 80mph to 87mph.
• September 1956: ZB introduced, with chrome side mouldings, revised dashboard, dished steering wheel and a full-width parcel shelf. Steering rack mountings changed from metal to rubber.
• ZB Varitone: two-tone paint and a larger wrap-around rear window, with flashing indicators. Early Varitones have a curved chrome flash over the front wheelarches and later ones a straight one.
• 1957: Manumatic semi-automatic option offered. It was unreliable, and dealers converted many cars back to manual.
• Axle ratios changed during production, from 4.3:1 to 4.875:1 and finally 4.55:1, which many cars now use.

Bodywork and structure

Almost every lower area of the monocoque can rot. Start with the inner and outer sills, then the lower rear wings behind the rear wheels, the rear spring hangers, the boot floor and the trailing edge of the bootlid. At the front, check the wing area behind the wheels where it meets the baffle plate, the lower front wings above the valance, the top seams of the wings, the area behind the headlamps, the bolt-on splash panels and, on the worst cars, the bulkhead and pedal box. Be suspicious of a lower front wing that has been joined to the sill and smoothed with filler, because it traps water. Doors rot from the inside along the bottoms, and water also gets in past the window weatherstrips. Rot that has spread into the floorpan is a warning sign of a major job. On a Varitone, check the larger rear window aperture for corrosion and confirm the shell is a genuine Varitone rather than a converted standard car.

Engine

The B-series is tough and usually needs attention around 100,000 miles. Look for blue smoke, listen for bottom-end noise, and ask about crankshaft and cylinder head history, since fatigue cracks and cracked heads are recorded. Twin SU carburettors can leak from dried seals or porous floats, and vapour lock is a known issue on hot days in traffic. Many cars run 1622cc or 1798cc B-series engines or an MGB head; uprated engines should come with matching brake and gearing changes.

Gearbox and drivetrain

Second-gear synchromesh is the known weak point. Listen for crunching on the change and whine from the axle. A five-speed conversion or later overdrive gearbox is a common improvement; factory overdrive was never offered. A car still on Manumatic is now very rare, and buyers should understand it may need specialist attention.

Suspension, steering and brakes

The front spring pans can rot badly enough to let the suspension collapse, so look at them closely. The rear-facing front tie rods can corrode and wear thin near the floor brackets, and broken tie rods are recorded; check their rubber bushes. Kingpins need regular grease. On the rack, check for split gaiters and column play from dry felt bushes. A car that pulls under braking usually has a seized or leaking front wheel cylinder. The system is single circuit, so fluid condition matters.

Electrics and interior

Cars were originally positive earth; many have been converted. Check the dynamo charges and lights work, and note whether trafficators or flashing indicators are fitted. Inspect the headlining for staining, which points to leaking screen rubbers that also lift the veneer on the wood dashboard. Leather seats sag, split and fade, and retrimming is one of the largest single interior costs. The original style of carpet is no longer made.

Identity and paperwork

Use the chassis number to confirm early or late ZA features and to check ZB and Varitone claims against the V5C. Record which engine, gearbox and axle are fitted. Brightwork is partly made of mazak, which pits and is hard to restore, so check every piece is present.

Most mechanical parts are available and reasonably priced, and repair panels for the common rust areas exist and are relatively straightforward to fit. Chrome and brightwork are the hard part. The Z and Farina Magnette Register of the MG Car Club (https://magnette.org) is the specialist group for these cars and publishes technical and modification guidance, alongside the MG Car Club itself (https://www.mgcc.co.uk). The MG Owners' Club (https://www.mgownersclub.co.uk) also covers the model.

• What welding has been done to the sills, floor, rear wings and front spring pans?
• Is the engine the original 1489cc unit, and if not, what else has been changed to match it?
• Have the front tie rods and their bushes been inspected or replaced recently?
• Is the car a genuine ZB or Varitone according to its chassis number and records?
• Is all the brightwork present and original, and what is missing?