OLD-SCHOOL GLOW PLUG RENEWAL

Glow plugs aren’t cheap, and I see guys at the flying field discard dirty ones, replacing them with new ones when they start having trouble with their glow engines. Often castor-oil residue can collect inside the plug and cause it to stop working properly. As long as the element coil isn’t damaged, most old glow plugs can be cleaned to restore their performance. Fill a glass jar with some Varsol solvent; using a holding board with holes in it to support the glow plugs, submerge the glow plugs and let them soak for a few hours. Swishing them around every once in a while helps dislodge the burnt castor-oil residue. This works well, and I have some cleaned glow plugs that are many years old. They still work great!