Standard reconditioned engines restore the MGA's BMC B-series to factory specification. Remanufactured by Ivor Searle, who have specialised in engine reconditioning for over seventy-five years, each engine is rebuilt to tight modern tolerances with improved surface finishes. The rebuild process includes a rebored block with new pistons and rings sized to the next available oversize, a reground crankshaft with new main and big-end bearing shells, new camshaft bearings, a reconditioned cylinder head with recut valve seats, new valve guides, and new valves where required. All gaskets and seals are renewed, and every assembled engine is validated in purpose-built test cells before dispatch.
All reconditioned MGA engines are supplied with lead-free-compatible cylinder heads, allowing safe operation on either unleaded or leaded fuel.
Identifying Your Engine
Three pushrod engine types were fitted across MGA production, and the correct one must be specified. The 1489cc engine (prefixes 15GB and 15GD) was fitted to the MGA 1500 from 1955 to 1959. The change from 15GB to 15GD occurred at chassis number 61504, when the starter motor was raised to a higher position on the engine, this change also affected the gearbox mounting plate and tunnel arrangement. The 1588cc engine (prefix 16GA) was fitted to the MGA 1600 from 1959 to 1961, sharing its bore size with the Twin Cam but retaining the pushrod valve train. The 1622cc engine (prefix 16GC) was fitted to the MGA 1600 Mk II from 1961 to 1962, with two compression ratio options: 8.9:1 (suffix H, standard for home-market cars) and 8.3:1 (suffix L, for markets requiring lower-octane fuel).
What Is Included
The reconditioned engine is supplied as a complete long engine with all internal components fitted and torqued to specification. It is supplied less ancillaries: flywheel, starter motor, distributor, and manifolds are not included and are transferred from the outgoing engine, along with the carburettors, clutch, and external pipework. When transferring ancillaries, all gaskets and seals at the mating surfaces should be renewed as a matter of course.
Exchange Basis
Reconditioned engines are supplied on an exchange basis. An exchange surcharge is applied at the time of order and refunded when the returned core is received and assessed as suitable for reconditioning. Engines with cracked blocks, broken crankshafts, or damage beyond economic repair may not qualify for the full exchange refund. All engines are built to order, so lead times should be checked at the point of ordering.
Compatibility and Fitment
Because many MGAs are now over sixty years old, it is not uncommon to find a car fitted with a non-original engine, either a different MGA engine prefix or a B-series unit from another BMC vehicle such as a Riley, Wolseley, or MG Magnette. Checking the engine prefix against the car's chassis number is essential before ordering. A 15GD engine fitted to a car originally supplied with a 15GB unit will require the later gearbox tunnel, toeboard, and carpet to be present, or the earlier 15GB specification engine must be ordered instead.
Ordering Notes
When ordering, provide the full engine serial number (prefix and number), the car's chassis number, and the intended bore size if known. If the engine has been previously rebored, the current bore size should be measured before ordering to confirm the next available oversize. Standard oversize increments are +0.010", +0.020", +0.030", and +0.040", blocks bored to +0.060" or beyond may require assessment for suitability.