Construction of Spark Plug Cleaner:

A push button is located on the body of the equipment is pushed to supply ignition voltage to the spark plug during gap test. Air valve control, is a wing type handle on the top of the equipment and “Air” is marked on it. This valve control has three positions “OFF”, “AIR” and “SAND”. This control is used to control the flow of air and sand during sand blast cleaning of spark plugs. One needle valve is located to increase or decrease the air pressure during spark test by rotating it anti clockwise and clockwise respectively. Pressure gauge is provided on the equipment to record the pressure applied during the spark plug gap test. Mirror, a metal mirror is mounted at an angle to the rear of the plug test opening, is used to observe the action of the spark during the gap test. Adaptor and gasket are provided to install different size spark plugs in the test opening. Gap gauge, is provided for the purpose of checking and adjusting spark plug gaps.

Working of Spark Plug Cleaner:

Connect the air line from 125-150 psi air supply to the rear of the air control valve. Ground the equipment properly otherwise the spark gap test won’t be up to the mark.

a. Sandblast Cleaning: clean the spark plug of any excess oil or water and insert in the opening. With the left hand, turn air control valve to “sand” position. Oscillate outer end of the plug with a circular motion, so that cleaner blast can penetrate all crevices, for about 5 seconds. Without removing plug from the opening, turn valve to “Air” position and again oscillate plug for a few seconds to clean out all particles of loosened carbon. Return the air valve to “off” position and remove the cleaned plug. Shake out any particle of abrasive remaining between plug porcelain and shell.

b. Gap Testing: Adjust gap of the old plug and screw old plug in the openings. Clip high tension lead to the plug to be observed. Regulate air pressure to correct amount for plug being tested. Press the test button, gradually opening needle valve until the pressure has been around 20psi above normal. While pressure is being increased, observe action of the spark in the mirror to see if the spark remains bright and steady, without flickering or missing.