Propane Conversion: How to Make LPG Cars

Liquid propane can be a low-emissions alternative fuel for cars. With the right vehicle and know-how, you can have a natural gas car.

The photos shown here and in the next image in the Gallery illustrate a dual-fuel conversion made to the personal car of James Couillard, Editor of LP-GAS Magazine. The automobile is a 1966 Chevrolet Impala with a 283 cu. in. V-8 engine. Bud Eggen, Northern Propane Gas Company's carburetion specialist in Alexandria, Minnesota — assisted by Harlam Dreger — performed the job in less than four hours. The feature from which this sequence is taken originally appeared in the May, 1970 issue of LP-GAS and has been taken from an IMPCO reprint at the suggestion of Walter Blouch.1. Plan location of all component parts. Use convertor and fuel filter lockoff mounting bracket ( ->) ifossible, for neatness and stability. Note that the carburetor adapter( -> ) is mounted directly on the original gasoline carburetor. Only the air cleaner assembly has been replaced. 2. When planning water line installation, use separate openings on heads and water pump to keep separate from car heater. If this is not possible, tee into heater lines close to block. Eggen used black iron tees. 3. Tighten screws on convertor, fuel filter lockoff and carburetor before installation. This procedure could well eliminate a later service call or a dissatisfied customer. 4. Always mount the convertor ( -> ) in an upright position. It should be as close as possible to the carburetor ( -> ) thereby keeping the vapor hose short. 5, 6. Push lock hose fittings are used for appearance, durability and ease of installation. 7, 8, 9, 10. When measuring and installing water lines, make sure hot water from thermostat side of engine is going to lowest convertor water opening ( -> ) and line from pump suction side of the water pump is going to the convertor's highest opening ( -> ). 11. Note neat appearance of water line installation by using push lock fittings and hose.