Fresh-air motoring from the USA
Where have all the air-cooled cars gone? In this day and age, with very reliable anti-freeze and cooling systems that do not admit of boiling, no need for it perhaps. But I sometimes dream of not having to lie awake wondering whether the freeze-avoiding liquid has been changed for fresh or is of correct strength, or if my car’s radiator has a leak. Had I motored in the days of the Franklin I could have been free of such worries, because this was an air-cooled car.
The Franklin was, indeed, quite unusual, at a time when cooling cylinders only by air was restricted to small cars such as the Rover 8, GN, some Morgans, and most of the cyclecars. So the Franklin was almost unique, one might say.
It had a wooden chassis, full-elliptic springing and wood artillery wheels, and relied on rear-wheel brakes only until 1928. It would not have suited the bulk of British buyers. Even when sales of the celebrated VW Beetle had exceeded those of the Model-T Ford over a shorter production span, there were people who could not stomach its unconventionality. An avid Beetle enthusiast, although not in the pay of Germany or the efficient British agents as some MotorSport readers imagined, when a neighbour with a Hillman Minx wanted a new car I invited him to look at my VW.
Opening the well-sealed back boot to show him the flat-four engine he asked where was the radiator? I showed him that plenty of luggage would go into the front boot, but I could see that without accepting a ride he would purchase another sensible water-cooled job with its cylinders in-line surrounded by water, engine properly located ahead of the driver. I don’t think he would have bought a Franklin!
There were many Franklin models, even a straight-eight and a 1932 conventionalised V12, and many specification changes. Best remembered is the Type 12B 30/6. It had a counter-balanced crankshaft with seven main bearings, and pushrod overhead valves. The 3871cc (with bore and stroke of 82.5 x 120.7mm) engine with conrods of duralumin and alloy pistons was cooled by a frontal scirocco fan taking in air from a circular opening in the dummy radiator. It forced air at high speed into a duct over the valve gear and tops of the cylinders, before it was exhausted through a copper-flanged surrounding over the cylinders. This system provided 2267sq in of cooling surface for each cylinder, with 2700cu ft of air flowing through it at an engine speed of around 1700rpm. Copper fins were so placed that the cylinders received air front and back.
A six-branch inlet manifold drew from a single Stromberg carburettor, exhaust-heated, with electric primer. Feed was by Autovac and a three-way tap on the rear-mounted petrol tank gave a reserve supply of fuel. At 3000rpm some 67bhp was claimed. A dry-plate clutch and three-speed gearbox was used, with adjustable clutch and brake pedals. The chassis was of three-ply laminated ash. The full elliptic springs were underslung, with a tubular front axle. Eventually Lockheed hydraulic brakes replaced the original transmission and back-wheel braking. The gear ratios were 17.14, 8.27 and 4.73-to-1, and it came with 32 x 6in balloon tyres.
In Britain the sales were handled by A-M Motors at 21 Chilworth Street, Paddington, W2; the cost of a five-seater saloon on the 9ft 11in wheelbase chassis was £885.
Several American manufacturers tried air-cooling but none could equal the success of H H Franklin’s products. It was claimed that the unusual springing with its 3.5in deflection saved tyre wear, and therefore Franklins for many years did not even have detachable rims.
In 1915, a Franklin was driven from Walla Walla, Washington State, to San Francisco in bottom gear without overheating. Charles Lindbergh of solo transatlantic flight fame used a Franklin, as did the author Gilbert Frankau who in 1930 bought a used Franklin, a make of which he had scarcely heard. At first it suffered front-wheel shimmy on the Colnbrook bypass. That cured, he drove this 4.5-litre Speedster Coupé on long French tours, seeing 90mph on a slightly optimistic speedometer downhill between Avignon and Fréjus. It climbed the snow-piled Furka, the Stelvio with its 87 hairpins, and the Katchberg, the last miles of which were, he said, “as steep as Brooklands Test Hill.”
A sporting Airman model was introduced in 1933, but the firm closed down in ’34, taken over by a firm making aero-engines.