Vehicle Conversion and Installation Flashcards
7 cards from real CNG practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Vehicle Conversion and Installation flashcards as text
What is the typical service life of a Type 3 (aluminum liner, full composite overwrap) CNG cylinder used in light-duty vehicle conversions?
Answer: 20 years from the date of manufacture
Type 3 cylinders are typically certified for 20 years from manufacture date, after which they must be removed from service.
A CNG vehicle conversion shop discovers that a customer's vehicle has a cracked engine mount. What is the correct course of action?
Answer: Repair the engine mount before proceeding with the CNG installation
Pre-existing structural defects must be repaired before a CNG conversion to ensure safe cylinder mounting and overall vehicle integrity.
Which of the following is an approved method for supporting a CNG fuel line that runs along the vehicle frame?
Answer: Clamps or brackets spaced no more than 24 inches apart
CNG fuel lines must be supported with rigid clamps or brackets at regular intervals (typically ≤24 inches) to prevent vibration damage.
In a bi-fuel CNG/gasoline conversion, what prevents the vehicle from running both fuels simultaneously?
Answer: The fuel selector switch and ECM logic that disables one fuel injector bank while the other is active
The fuel selector switch combined with ECM logic ensures only one fuel system is active at a time, preventing dangerous simultaneous fuel delivery.
What is the correct procedure when a CNG cylinder shows visible damage such as dents or abrasions deeper than the composite overwrap?
Answer: Remove the cylinder from service immediately and have it inspected by a certified cylinder inspector
Any damage that penetrates the composite overwrap compromises structural integrity and requires immediate removal from service pending expert inspection.
Which electrical connection is required between the CNG cylinder valve and vehicle chassis on many conversion kits?
Answer: Bonding wire to prevent static electricity buildup
A bonding wire equalizes electrical potential between the cylinder and chassis, preventing static spark ignition near the CNG fuel system.
When installing a CNG cylinder in a pickup truck bed, the cylinder must be protected from cargo impact by:
Answer: A protective cage or barrier rated to prevent contact with the cylinder
A rigid protective cage or barrier is required to prevent cargo from striking and damaging the high-pressure cylinder.