ASVAB Automotive Information Practice Test 102435

Questions 5
Topics Coolant, Power Stroke, Shock Absorbers, Solenoid, Transfer Case

Study Guide

Coolant

Modern car engines are cooled by liquid which circulates through the engine block and cylinder heads absorbing excess heat. This liquid is made up of half water and half antifreeze (commonly, ethylene glycol) which both keeps the water from freezing at low temperatures and raises its boiling point making heat transfer more efficient.

Power Stroke

During the power stroke, just before the piston reaches top dead center, the spark plug fires and ignites the compressed air-fuel mixture. The resulting expansion due to combustion pushes the piston back down the cylinder toward bottom dead center.

Shock Absorbers

Because a compressed spring will ex­tend violently, shock absorbers must be used to dampen the spring’s compression and extension cycles. Struts combine the spring and shock into one unit

Solenoid

The cylindrical solenoid is a relay that safely connects the high amperage battery to the starter motor when the ignition key is turned. This current then allows the engine to turn at a high enough speed to start.

Transfer Case

The transfer case splits engine power between the front and rear axles of four-wheel drive vehicles.