AUXILIARY EXHAUST


| September/October 1968



Tractor

Courtesy of Art Dickey, Shantytown, Iowa 50060

Art Dickey

1615 San Francisco St., San Antonio Texas 78201

(Herewith is one of Mr. Kruger's interesting letters that has slipped past a few issues but is worth printing anyway as I know you fellows have your books and refer to items in discussion. This letter was written last September - Anna

On top of page 26 of the July-August 1967 GEM is the question by R. H. Moore, why part of the exhaust is piped back to the piston-skirt. Well, probably I shouldn't be 'opening my mouth', since I have no original literature on the 'Domestic' engines, let alone this particular one in question by R. H. Moore. As to it's horse power, I'd say it right is at 4 Hp. At first thought, the top pipe on Moore's engine is the 'auxiliary exhaust', piped back to the discharge port of the exhaust valve. I have never imagined an auxiliary exhaust outlet at the top of the cylinder, at the point where the cylinder oil is usually placed. Maybe, this was an idea some mechanic 'cooked up' himself. Anyway, the pipe leading from the top of the cylinder to the usual exhaust piping, is quite small. But, be it as it may, the idea is good, and will allow the cylinder to operate at a lower temperature.

As some of you will recall the 'Gade', engines have been using the auxiliary exhaust. I have no literature on the 'Gade', but, here are some of the feature points I have read about through the 'Gade' advertising in early farm magazines. The same would apply to the 'Domestic' engine and Moore's question.

The auxiliary exhaust port is usually placed at the side of, or bottom of, the cylinder, (horizontal engine). This port is so placed that the piston will uncover it at the end of the power stroke; and, of course, at the end of the intake stroke also. I have never used an engine so equipped and I don't know why the feature has been discontinued. It could be, that at the end of the intake-stroke, with port uncovered, some products of combustion, or air, could enter the cylinder thru this port and interfere with the fuel air ratio of the incoming charge thru the fuel mixer.

Anyway, the 'Gade' people claimed the auxiliary exhaust was the 'berries' in cooling their engine cylinders; their air-cooled types, without a fan and the hopper-cooled types, without water, for the lighter loads; using water in the hoppers for full load work-all the while giving more power on less gasoline. Their motto for the 'gade', 'The engine that breathes.'