Cheez. Propane and LNG have been used in tractors forever, with zip problems. If the Dallas police had problems, it was probably due to crappy workmanship in the conversion. Cars have been running on propane for decades, with no problems (and in actual fact, due to the cleaner nature of the fuel, they last far longer).
Yes, I know. However, those tractors had larger fuel tanks than the gas or diesel variants. Look at pics of the 1960’s Deere LPG tractors - they have this tank coming up through the cowling in front of the operator’s position:
http://underwoodequipment.net/yahoo_site_admin/assets/images/100_0368.175194832_std.JPG
Or check out any Schwans’ truck:
http://cache.daylife.com/imageserve/00CJ2prbMeaLj/610x.jpg
See that big white tank on the side, rear of the cab? There’s another one just like it on the other side too. If it ran on diesel, they’d have the same range with just one of the tanks.
The problem in a cop car is likely this: they can’t sacrifice their trunk space for a larger fuel tank. They have radios/computers/emergency supplies/tactical equipment in the trunk of a cop car. So they’re likely stuck with the volume that they had in a gasoline tank. Now fill the volume of a gas tank with LPG or CNG and you have a pathetic range.
Other than that, I agree with you. There are guys running irrigation engines on LPG or NG and they run forever, need only about 1/10th of the oil changes that a diesel needs, and overhauls about 1/10th of the hourly rate of a diesel.
