MGA

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Every 12,000 miles, re-lubricate the steering rack (a single nipple on the rack; apply up to 10 strokes of the grease gun, plus a single nipple on the pinion shaft; apply two strokes of the grease gun).

How easy are they to work on?

In most respects the MGA is very user-friendly when it comes to routine servicing, and there are no serious difficulties for d-i-y enthusiasts.Almost all ignition system operations, also checking/re-setting the valve clearances, and attending to transmission and running gear lubrication aspects are straightforward. It’s not all good news, though. Access to the engine from above is a little restricted because of the narrow bonnet aperture. In addition, removing and re-fitting the oil filter assembly are time-consuming operations (partly due to restricted access). The distributor is mounted low down within the engine bay, and also comparatively difficult to reach. Setting up the twin carburettors takes longer than dealing with a single instrument, but is not difficult. The parts required for routine maintenance are all readily available from a range of specialist suppliers; prices are reasonable. Despite the minor grumbles referred to above, overall the MGA is a pretty easy classic to look after at home.
Note 1: Mileage/time intervals shown here are suggested for typical use; frequency will need to be increased under harsh operating conditions.
Note 2: MGA specifications changed during production; please consult manufacturer’s literature for full details of each aspect of maintenance, specific to your version.
Note 3: The main feature covers the popular 1500 and 1600 models (but not including the Twin Cam, which has specific engine maintenance requirements; please consult dedicated box out below).

MGA Twin cam models - brief information

Far more complex than the overhead valve (pushrod) MGAs, The Twin Cam versions sold in small numbers and early examples earned a reputation for unreliability, although in truth the cars are far more dependable than hearsay indicates. The Twin Cams require attention to detail and some dedication in order to get the best from the cars. The engines are far more difficult to look after at home in terms of valve gear than the pushrod motors (with, for example valve clearances controlled by shims, and a timing chain some 13 feet or approximately four metres long).

Useful Twin Cam engine information:

Capacity/power: 1588cc, 108bhp
Engine oil capacity, including filter: 13 pints (7.38 litres)
Valve clearances: 0.014 to 0.015in cold
Spark plugs: Champion N3 or equivalent (N58R for competition work), gap 0.025in
Contact breaker gap: 0.014 to 0.016in
Ignition Timing: Top Dead Centre (TDC)
Firing order: 1-3-4-2

Ignition

Firing order: 1-3-4-2 (No. 1 cylinder at front of engine) Spark plugs: Champion NA8 (early examples) or equivalent; or N5 or equivalent. Gap 0.024in to 0.026in. Every 6000 miles or annually (whichever comes first), check and clean the plugs; renew regardless every 12,000 miles. Contact points: Gap 0.014 to 0.016in. Every 3000 miles or annually (whichever comes first): Check and clean the contact points (renew points regardless every 6000 miles). Clean and check distributor cap, rotor arm and high tension leads; ensure that all connections are sound. Distributor - mechanical aspects: Remove the rotor arm and apply a few drops of engine oil to the moving contact pivot, distributor shaft/cam bearing and mechanical advance mechanism (through apertures in the distributor’s baseplate). Apply a smear of high melting point grease to the distributor cam. Timing: Check/re-set, referring to the fixed pointers on the timing case (representing TDC, 5 degrees BTDC and 10 degrees BTDC) and the notch on the crankshaft pulley rim. Use the following settings as starting points (further fine-tuning may be required following a road test):
1500: 7 degrees BTDC
1600 Mark I: 6 degrees BTDC
1600 Mark II High Compression - to Engine No. 4003: 10 degrees BTDC
1600 Mark II High Compression - from Engine No. 4003: 5 degrees BTDC
1600 Mark II Low Compression: 10 degrees BTDC

Fuel System

Every 3000 miles or annually (whichever comes first): Examine all fuel system pipework and check/top up the carburettor dashpots with SAE 20 oil. Examine/clean the filter in the fuel pump. After the valve clearances and all ignition settings have been checked/set, and with the engine fully warmed up, check/re-set the carburettor mixture/throttle stop settings (ideally use proprietary equipment for precisely balancing the carburettors). Always check throttle synchronisation (flexible rubber or plastic tubing can be used for this as an alternative to proprietary equipment; listen through the tube to asses the degree of ‘hiss’ evident at each carburetor intake in turn). The volume of air entering each carburetor should be identical. Always assess the mixture strength for each carburettor in turn. First lift the suction piston on one carburettor by 1/2in (approx. 13mm), so that the engine is running on the other carburettor alone. Now lift the piston on the operational carburettor by 1/32in. This should cause the engine to speed up a little, while running smoothly. If the engine stops, the mixture is too weak. If it continues to speed up when the piston is lifted by 1/4in, the mixture is too rich. Corrections can be made by rotating the hexagonal adjuster at the base of the carburettor. Repeat the entire procedure for the second carburettor. Every 6000 miles, examine the air filter elements and clean/renew if visibly obstructed (clean/renew regardless every 12,000 miles). At every service, ensure that the breather pipework is unobstructed.

Engine

Overhead valve (pushrod), in-line four-cylinder BMC B-Series 1500: 1498cc, 68bhp (later examples, 72bhp) 1600: 1622cc, Mark I, 80bhp; Mark II, 93bhp.

Valve Clearances

Check every 12,000 miles. Recommended ‘hot’ clearances are: 1500: Inlet and exhaust, 0.017in; 1600: Inlet and exhaust, 0.015in. Adjustment is by screw and locknut. Use the ‘Rule of 9’; check/adjust valve No. 1 with No. 8 fully open, No. 2 with 7 open, No. 3 with 6 open, and so on (in each case sum of valve numbers is 9). Spanner sizes: Rocker cover bolts, 5/8in AF; adjuster locknuts, 1/2in AF. Fit a new rocker cover gasket on re-assembly, unless the original is in excellent condition.

Cooling System

All year round, use top quality anti-freeze mixture containing corrosion inhibitors. Every 3000 miles/annually, check the radiator plus its cap, all hoses and their connections, the water pump and the fan assembly. At least every three years, drain the system, remove the radiator, take out the thermostat and reverse-flush the entire system prior to re-filling with fresh anti freeze solution (observe the dilution recommendations of the anti-freeze manufacturer - these are printed on the container). Capacity, including heater: Approx. 10 pints (5.68 litres).

Lubrication

Engine oil: Every 3000 miles or annually (whichever comes first): Change the oil and filter (after warming the old engine oil during a long run). Use high quality, SAE15W50, 20W50 or 20W60 oil. Please dispose of the old oil in an environmentally friendly manner - local councils provide waste oil collection points.
Notes: 1. Sump plug spanner size, 3/4in AF (socket or ring). 2. To change the oil filter, on early cars it is necessary first to detach the oil feed pipe from the filter housing. On all versions, unscrew the housing through-bolt (5/8in AF spanner) and remove the filter assembly. Take out the old filter element, then clean all the housing components in fresh paraffin, wipe dry and carefully re-assemble with a new filter element. On re-assembly, partially fill the housing assembly with clean oil. Note that the filter is spring-loaded within its casing, and re-installation of the filter housing to the engine (against spring pressure) can be difficult. To prevent problems during re-assembly on early engines, push the filter element down inside the bowl (against the spring pressure) and temporarily insert a metal rod through the oil feed aperture in the housing. Install the assembly, withdraw the rod and re-connect the feed pipe on completion. Sump capacity: Approx. 8 pints (4.546 litres), including filter.
Gearbox oil: Every 3000 miles/annually (whichever comes first), check/top up the gearbox (with the car horizontal). A gearbox dipstick is provided; this is reached from inside the car, after removing a rubber plug in the transmission tunnel. Every 12,000 miles (approximately), drain the gearbox (after a long run, when the oil is fully warm), then refill with fresh lubricant, to the same specification as that used in the engine. Gearbox capacity: Approx. 4.5 pts (2.56 litres).
Rear axle oil: Every 3000 miles/annually (whichever comes first), remove the filler/level plug and ensure that the lubricant is up to the base of the threads in the plug aperture. Every 12,000 miles (approximately), drain the axle oil after a long run, and re-fill with fresh lubricant. Use SAE90EP hypoid oil. Capacity, approx. 2.25 pints (1.28 litres).
Water pump: Where a lubrication point is fitted, every 6000 miles sparingly re-lubricate the water pump using SAE 140 gear oil.
Running gear: At least every 1000 miles, re-lubricate the front suspension and propeller shaft assemblies (use lithium-based, multi-purpose grease). Attend to these grease nipples: King pins (nipple at top and bottom on each side). Ball joints (single nipple on each). Propeller shaft (originally a single nipple on each universal joint - although the joints may have been replaced with ‘sealed for life’ types at some stage); all have a greasepoint on the sliding splines at the front of the shaft. Handbrake cable (single nipple). Ensure also that all handbrake mechanism pivot points are properly lubricated, and that they move freely.
Front wheel bearings: Every 12,000 miles, check the bearings and re-lubricate with fresh lithiumbased grease specifically stated as being suitable for wheel bearing use.
Steering rack: Every 12,000 miles, re-lubricate the steering rack (a single nipple on the rack; apply up to 10 strokes of the grease gun, plus a single nipple on the pinion shaft; apply two strokes of the grease gun).
Wire wheel splines: On cars fitted with wire wheels, whenever the wheels are removed, ensure that the hub splines are coated with copper-based, anti-seize compound (alternatively, use grease), to prevent seizure of the wheels on the splines. Check specifically to ensure that the splines are not worn (indicated by sharply pointed profiles); this is potentially EXTREMELY dangerous as the brakes may be rendered inoperative if the splines are not in good condition. Renew all worn components.
Other aspects:
Every 3000 miles, re-lubricate the carburettor pivot points/controls, also the accelerator pedal pivot. Every 3000 miles, re-lubricate the hinges and lock mechanisms (wipe off excess lubricant). Every 3000 miles, re-lubricate the clutch and brake pedal pivot points. Every 12,000 miles, re-oil the dynamo rear bearing (using a few drops of engine oil).

Brakes

At least every 3000 miles or annually, whichever comes first: Remove all the brake drums and examine the shoes, cylinders and drums (remove the drums for a complete check). On 1600 versions with disc brakes (and earlier cars which may have been converted) check the front pads, discs and calipers, as well as the rear drum brakes. In all cases scrutinise also the brake pipes, flexible hoses and master cylinder. Renew any ailing components AT ONCE. AVOID INHALING DUST FROM THE PADS/SHOES - IT MAY CONTAIN ASBESTOS. With car raised and securely supported on axle stands, and with the wheels clear of the ground, adjust the brake shoe to drum clearances as required. The adjusters - two for each front wheel and one for each rear wheel – are accessed through apertures in the wheels and brake drums. Using a large screwdriver, rotate the adjusters clockwise until the brakes are locked, pump the brake pedal to centralise the shoes, then back off the adjustment until the wheel rotates without binding. After adjusting the shoes at the hubs, as described, check handbrake operation and re-adjust the cable length if necessary (the adjuster nut is located on the cable under the centre of the vehicle). Always ensure that the brakes are not binding with the lever in the ‘off’ position. At least every two years, renew the brake fluid.

Sundry Items

Every 3000 miles, or annually (whichever comes first): Check the fan belt and re-tension if necessary (3/4 in. deflection at the centre of the belt run between the crankshaft and dynamo pulleys). Examine the clutch operating system hydraulics (including, notably, the master cylinders) for deterioration/leaks. Assess the cleanliness/security of all electrical connections; inspect all wiring for damage. Scrutinise the steering rack gaiters for splits/leaks. If damaged, the gaiters should be replaced at once, to prevent dirt and moisture from entering the rack. Assess the condition/security of all running gear components, the suspension mounting bushes and the exhaust system. Inspect the entire underbody for damage, and rectify paint blemishes. Every 12,000 miles, check engine compression readings. Every 12,000 miles, assess wear in the hub bearings. Every 12,000 miles, examine the springs for damage and shock absorbers for deterioration/leaks.