I'm a little late, but I hope everyone had a great 4th of July. I spent the holiday back home in southwest Iowa with family and friends I hadn't seen in a while. Like everywhere else, there were plenty of fireworks, in addition to another small rural town summer tradition – antique tractor shows, and even antique tractor pulls. Driving home from Missouri, I definitely saw my fair share of them getting ready. What I've seen more of lately is LPG, or liquefied propane gas tractors, which are considered somewhat rare.
When I first saw one – usually identifiable by the propane tank on top of the hood just in front of the steering wheel – I thought, "What is the point?" I apologize to my favorite fictional television character, Hank Hill, but until I did some digging, I still wondered just what the point was of using propane as a tractor fuel.
It turns out I’m not the only one who has asked this question – this is a hot discussion topic on antique tractor forums. Hank Hill would argue that propane is a cleaner burning fuel, leaving the engine cleaner after years of use and reducing emissions. Another point is that liquid propane was first introduced as a low-cost alternative to high-octane gasoline, according to Randy Leffingwell, author of books like Farm Tractors: A Living History, The American Farm Tractor, and Vintage Farm Tractors: History of the Farm Tractor.
Leffingwell writes that initially, liquid propane was a byproduct that didn't have a use until the 1920s. In 1930 kits were sold to allow farm tractors to run on propane. In 1941, Minneapolis-Moline introduced the first factory made liquefied propane gas tractor, and other companies followed, according to Leffingwell.
However, these tractors weren't without drawbacks. Propane has less BTUs, or less energy per gallon. With propane prices changing with the seasons, it can be more costly nowadays. Many have argued it can also be inconvenient to refill a propane tractor. However, there are others who argue with rising gas prices, liquefied propane gas is due for a comeback. In fact, there are some antique tractor owners who have converted to LPG.