by bgsengine » Mon Dec 18, 2023 5:14 pm
I always figured it was for a way to hook spark plug wire to tester when the straight-in terminal was a tight fit somewhere.. (short plug wire or some such.) I seem to recall some mention of its real purpose at one of the service schools we went to long ago, but it was so long ago I can't remember details - As you may recall the original version was a "donut" of basically High Density Fiberboard with threaded screws ground to points and locknuts to lock adjustment in place and an alligator clip on the ground side. later updates put plexiglas windows on the tester, and then they went to the current version.. I tried to look up the patent for it, but have had no luck finding an original patent, which WOULD describe and detail the true purpose (I believe it is legacy design from when ignition systems used breaker points, magnetos, etc. Possibly something to do with testing the KV strength of the spark...)
How poor are they who have not patience. What wound did ever heal, but by degrees? - Iago (Othello Act II, Scene 3)