How to Convert a Vehicle to Propane

Safer for the environment and priced lower than gasoline, liquid propane offers a fuel alternative designed for long-range driving. While you can convert almost any gasoline vehicle to propane, in the United States, you'll find mostly companies and local governments using it at this time. That means you will need to work a bit harder to convert your personal car for use with propane.

Instructions

Difficulty: Moderate

Things You’ll Need:

• Conversion kit
• Qualified conversion contractor
• Propane
• Hose

1. Start with a well-maintained vehicle. The process is simpler when the car doesn't have any problems before you convert it.
2. Decide which type of conversion system you want to install. An open-loop system does not control electronics, which means you cannot gauge how well it is performing. A closed-loop system incorporates a sensor that provides continuous data on performance and adjusts the fuel/air ratio as needed. A closed-loop system is more expensive.
3. Check your warranties. While some states require conversion kit manufacturers to provide a comprehensive warranty, you may also be voiding your original warranty. Any warranty should cover the propane system and any mechanical failures caused by it.
4. Purchase a conversion kit, which includes a fuel controller (carburetor), valves, tank, actuators, electronics and software. Make sure your kit works with your engine. The engine on the same model of car can differ depending on the year. You can also buy the supplies separately.
5. Mount a liquid propane tank in your vehicle. In a passenger car, the tank fits in the trunk, while in vans and trucks it replaces the gasoline tank under the vehicle.
6. Run the liquid propane hoses so that rocks, curbs and road irregularities will not damage or crush the hoses.
7. Modify the engine according to the conversion kit manufacturer's instructions. You'll need to adjust the cam timing and compression ratio.
8. Install an electronic shut-off valve for safety. The valve isolates the propane from the engine when the car is turned off and will stop the propane flow during an accident.
9. Fuel up the car, checking for leaks. When you first start the car, you should check for leaks near the filter and then adjust the timing. Most cars will be set to idle faster than needed for propane use.
10. Maintain the car as normal, keeping a close eye on the spark plugs. Most problems with converted cars can be traced back to the spark plugs.

Tips & Warnings

• Although converting your vehicle to propane may be expensive, a portion of your cost is deductible from your federal income tax.
• Your conversion must meet EPA standards (and CARB in California), which means you must, as an individual, work with a group to attain proper certification.
• Converting your car to propane is not a do-it-yourself job. You should find a qualified contractor to do the necessary work.