Veteran Edwardian Vintage


Ford Crankshafts

A MINOR item of motoring history concerns the evolution of crankshafts for Ford motor cars. When reading J.W.'s article in the March issue about the Rally Fiestas I noted that he referred to the "iron crankshaft" of the Kent cross-flow engine used for some of these cars. This occasioned no surprise, because for a long time Ford has used cast-iron crankshafts. The question posed is, when did they achieve this breakthrough?

I had thought the change from steel to iron for this essential engine component had been made at the time of that other great Ford breakthrough, the advent of their low-cost vee-eight-cylinder power unit, in 1932. At a time when multi-cylinder engines were popular for quite ordinary cars - I covered some of the aspects of the once-coveted straight-eight type of engine last month - Henry Ford was determined to have a V8 for his new model that was to follow the then-current four-cylinder Model-B and its derivatives. At this crucial time Chevrolet was again winning the American sales-race, with an overhead-valve six-cylinder offering, and the Chrysler-built Plymouth PB, with its fourcylinder engine on "Floating-Power" mountings and with hydraulic brakes, was a tough competitor, with a new six-cylinder Plymouth PC in the offing for 1933.

Statistics are sometimes tricky things to wield, but it is generally accepted, I think, that Chevrolet made 63,464 more vehicles in the 1932 calendar-year than Ford, and that Henry Ford's 1932 production target of 1,500,000 fell sadly short. Ford had never liked the six-cylinder engine since his not-very-successful 6-litre Model-K of 1904 and was now determined to bring out his low-cost V8, inspite of the disruption this caused to production schedules. It is interesting to remember that his arch-rival, Chevrolet, had dabbled with a vee-eight many years earlier, This did not bother Henry Ford, for at that time he was outselling Chevrolet with his Model-T in the ratio of 12-to-1 and making that automobile at a fifth of the cost of the 288 cu. in. 8-pot Chevvy. Ford had his own vee-eight at that time, too, in the form of the prestigious Lincoln V8, introduced in 1922. But the problem was to employ an inexpensive power-pack of this type. It was not possible to scale-down the Lincoln or any of the other vee-eight engines, which were expensive to manufacture, with their separate crankcase and cylinder blocks, and complex inlet and exhaust manifolding, etc. Packard had set high standards of smooth-running, refinement and dependability with their in-line-eight by 1931 but this type of eight was too long for installation in a people's high-performance car.

These factors were what made Ford experiment with new foundry techniques until it was possible to cast, in iron, the crankcase and the two cylinder blocks in one piece, for his new V8, and not only that, but to core the exhaust ports within the cylinder blocks. The story of the problems that had to be solved by the unfortunate Charles Sorensen, who had been given the task of producing this new concept of a vee-eight, the ignition and carburation problems then encountered with the prototype Ford V8 engines, and the chronic overheating troubles, frame weakness, etc. of the first production examples, has been well told elsewhere in "Ford In The Thirties" by Paul Woudenberg, Ph.D (Peterson Publishing Co., Los Angeles, 1974) and in "Forty Years with Ford" by Charles E. Sorensen himself (Jonathan Cape, 1957), for instance.

The Ford Motor Company had intended to commence production of the new V8 cylinder block moulds at the rate of 100 per hour in a continuous operation and it is a fact that, in spite of all the complex new tooling and foundry operations involved, the V8 block was machinef-inished at a new low, in terms of unit cost. Thus this brilliant new power unit was persuaded into production, in spite of the fact that ten months prior to the intended announcement date, in the fall of 1931, the engine had scarcely been run, serious dynamometer testing not beginning until June of that year. All manner of changes had to be made to the exhaust porting, to the carburetter and fuel pump, and to the ignition distributor, etc. (Experts have it that the carburation problems were not properly overcome until late in 1933, and that the overheating wasn't cured until the water pumps were repositioned in 1937.)

However, spurred on by the knowledge that Chevrolet had sold 74,848 more vehicles than Ford in 1931 and was out-selling him again at the beginning of 1932, Henry Ford was determined to get his brilliant new project on the market, and when the first Model-18 V8 was released to the public on March 30th, 1932 it is said that more than 5,500,000 people visited Ford showrooms in America on that day, the numbers increasing in the next few days, in spite of the prevailing financial depression; alas, deliveries could not be met immediately, because only 1,000 V8s existed. There may not have been the World-wide excitement that the Model-A's debut, as replacement for the long-lived Model-T Ford, had provoked in 1927 but there must have been much speculation about the new multi-cylinder Ford, for as late as December 1931 Business Week, in their Christmas issue, apparently wasn't sure whether Henry was going for a straight-eight or a vee-eight.

When it was released, the new V8 looked outwardly like a four-pot Model-B, except for the V8 badge on its tie-bar between the headlamps, until restyled for 1934, by Eugene Gregorie, as the Model-40. Ford had to face critics who predicted heavy gas-consumption from an eight, rapid wear occasioned by the admittedly scintillating performance, and also uninformed opinion that thought the pistons would wear rapidly on one side because they did not reciprocate vertically. It all proved unfounded, and if, as has been shown, Chevrolet sales outstripped Ford's in 1932, after the V8 had got to the customers, from June of that year onwards, the position changed, with the Model18s and Model-Bs selling a total of 195,988 by the end of December, whereas Chevrolet had sold 57,839 fewer cars in that period. Moreover, once the Ford engineers had got to grips with the early problems the new V8 was decently reliable, if perhaps under-braked and too casually steered, for its effortless acceleration and top speed. This wasn't so with its rivals. The new Chevrolet Six had back-axle troubles, necessitating four redesigns between 1930 and 1933, it ran bearings, with its splash-lubrication, which persisted even after the engine had been converted to pressure lubrication in 1935, and it is said that it wasn't until that year that its inherent problems with the overhead-valve-gear were solved. Whereas the pressure-fed, side-valve Ford V8, soon restyled, went on to unquestionable success, and the mechanical concept was carried on to the low-cost V12 Lincoln Zephyr, announced in 1936. With all this clever concentration on vee-engine layouts, I find it stimulating that Ford of Britain's present top models in the private-car and commercialvehicle fields use excellent V6 power-packs.

All this has taken me some way from the topic I opened with, namely the composition of Ford crankshafts. Originally, Ford used forged steel crankshafts, as did almost all other manufacturers, with specialist cars like Bugatti, Sunbeam, Hispano Suiza and Roesch Talbot having their crankshafts machined out of solid steel billets, wasteful of material for ordinary engines. Both the aforementioned books indicate that Ford was using forged crankshafts for the first Model-18 V8. Steel is not actually specified in Woudenberg's book, and Sorensen, after describing how the revolutionary one-piece rigid V8 block was able to be cast in iron, after research which was under his control and that of Joe Galamb and Hanson in the formative stages, goes on to say that the V8 crankshaft started as a forging but that he and H. McCarroll then searched for a steel that could be cast and would still meet the physical requirements of a crankshaft. After much experimentation they found a steel that was better crankshaft material than any other suitable forging bar. The finished cast crank cost a dollar less than a forged crank, and the method was covered by patents. So we can conclude that the first, or perhaps the early production, Ford V8s had cast-steel crankshafts. But when did Ford make the next breakthrough and use cast-iron crankshafts? (I am aware that a careful definition is called for here, the cast-iron used by Ford sometimes being referred to as chrome silicon cast-steel; as it has only about 5 1/2% of alloys, the rest being iron, the steel designation is incorrect.)

The changes in engine materials to some extent mark the distinction between the vintage and the post-vintage engines. Whereas at one time the cylinder block would be separate from the crankcase, and the crankcase closed by an aluminium sump, the one-piece cast-iron or steel block and crankcase took over and the sump soon became a tin pressing. The Austin Seven was one of the last utility engines to retain a separate block and alloy crankcase, even though the latter was closed by a tin oil-tray. Mostly this remains true today, except for a few aluminium engines, as in the Rover 3500 V8, etc. Pistons changed along the years from cast-iron to steel and then to aluminium, although early steel pistons were apt to wear quickly and sometimes a change back to cast-iron was made. Cylinder blocks have been made of iron, steel and aluminium but I think the mention of cast-iron con.-rods in the Lagonda Book referred to recently was a misprint, these being mild steel or duralumin stampings, but sometimes steel forgings. Cylinder heads have been of iron, steel, bronze and aluminium and the late Laurence Pomeroy left his brilliant designing at Vauxhall's soon after WW1 to try to promote an all-aluminium car in the USA. Any comments?