FINDING THE "MISSING" PLUG

Evening Star, Issue 22247, 27 January 1936, Page 13

FINDING THE "MISSING" PLUG

Although plug troubles are, exceedingly rare these days, sometimes an owmer who has never bothered to clean and adjust his plug points will, after long usage, experience a ping cutting out on the road. The operation of changing a plug is simple; the operation of finding which plug is at fault is sometimes a problem to the novice, who is forced to take out each plug to see which one is obviously at fault. The simplest method of detecting the faulty plug is by means of shorting it to the cylinder block or head, with a screwdriver. The procedure is easy. Keep the engine running at a steady speed. ' Place the end of the screwdriver on the engine close to the plug and without removing it from the engine press the shank, of the screwdriver on to the plug terminal. This will, of course, short the plug, and no shock need be feared unless the plug is touched before the cylinder block. If the engine hesitates and fires unevenly when shorting No. 1 plug, and runs more evenly when the screwdriver is removed, that plug is functioning properly. When one plug is found which ‘makes no difference to the firing of the engine whether it is shorted, or not, obviously that is the plug which is spearking at all and must be changed.