ASVAB Automotive Information Practice Test 496438

Questions 5
Topics Air-Fuel Mixture, CV Joints, Catalytic Converter, Shock Absorbers, Water Pump

Study Guide

Air-Fuel Mixture

The stoichiometric ratio defines the proper ratio of air to fuel necessary so that an engine burns all fuel with no excess air. For gasoline fuel, the stoichiometric ratio is about 14.7:1 or for every one gram of fuel, 14.7 grams of air are required. Too much air results in a lean air-fuel mixture that burns more slowly and hotter while too much fuel results in a rich mixture that burns quicker and cooler.

CV Joints

Constant velocity (CV) joints are located at both ends of a half shaft and their purpose is to transfer the torque from the transmission to the drive wheels at a constant speed while accomodating the up and down movement of the suspension. The inner CV joint connects the shaft to the transmission and the outer CV joint connects the shaft to the wheel.

Catalytic Converter

The catalytic converter converts pollutants in exhaust gas into less pollutant substances like carbon dioxide and water.

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

Water Pump

The water pump is driven by a belt connected to the crankshaft and ensures that coolant moves through the engine and radiator.