'Look Mamma No Plugs'


| May/June 1969



Cross-Mounted Tractor

Courtesy of Francis Sevart, 111 N. Cherokee, Girard, Kansas 66743

Francis Sevart

35640 Avenue F Yucaipe, California, 92399

I had just donned my kitchen apron after having returned from church last Sunday, and was poised before the kitchen window, overlooking Hubby's 'Back Shop', when the sound of screeching nails being pulled from well seasoned boxwood crating sent shudders up my back. So I hastily put the cake in the oven, which I had just whipped up, and reaching for my shorthand notebook and pencil began a trek out back to see what was going on, and if possible abate the very un Sunday like noise.

Upon reaching the shop, I witnessed the last of the crating boards being removed to expose what appeared to be an old-fashioned coffee grinder like we had in the Country Store way back when I was in pig tails. But while our old grinder with its two large flywheels and central vertical hopper was painted bright red and trimmed in gold, this 'grinder' was in deep brewster green and looked like it was built substantial enough to grind anything up to gravel.

'What are you adding to the museum, there?' I quiered, and as Frank gave me a side glance while clearing away the packing he replied, 'This is the latest import from Germany, a real little Diesel stationary engine intended to do the chores around the shop and farm, and even since the war there has been nothing like it manufactured in this country.'

'So what?' I countered, 'What will it do that the old Fuller and Johnson cannot do?' He was quick with the comeback, 'Look, Mamma, No Plugs!' 'I can see it has no boiler, so what makes it run?' I asked. 'This is the latest stage in the development of the art in honor of Rudolph Diesel,' he began, and continued: 'Rudy's original invention consisted of an engine following that utilizing the Carnot cycle as you may remember from your high-school physics. But Rudy went on to reason that if the compression pressure was raised high enough the resulting temperature would be high enough in the cylinder to ignite the fuel charge without benefit of a spark plug, igniter, or other device to start combustion of the charge in the cylinder. But this might result in erratic timing unless only air were compressed in the cylinder, and the fuel then injected only at the time when expansion of the enclosed gases should commence. Actually, Germany had lots of coal but no oil, so Rudy's first engine was constructed on the principle of utilizing an air blast to blow a charge of coal dust into the cylinder against the high compression pressure at the moment of ignition. Whereas, the compression pressure was in the neighborhood of 450 psig, the air pressure necessary to inject this charge of coal dust into the cylinder was near 600 psig.'

'Mr. Ed' Case 25-45 cross-mounted tractor owned by Francis. It was in the homecoming parade in Girard, September of 1968 and at the Pioneer Harvest Show at Ft. Scott in October.