Reply To: Delco coil # 2178 needed for 33 roadster

[Gregory Long]

Chris, beware that these old coils are subject to breaking down electrically. The insulation around the windings of the transformer inside the coil will start to leak electric current and the coil’s output will decrease or completely fail.

So check the coils on good running cars, to test that they work correctly. Often the coil will work when color cool, but as the coil gets warm and the engine bay get HOT, then the coil will start to fail

I’ve had one of these coils act just like a lean carburetor, as the engine warmed up, the car ran weaker and weaker, like a lean mixture, but no missing, or backfiring. and the coil always had a hot blue spark at idle, and the engine idles smoothly. but would have very low power.

Just don’t get lead astray by assuming that a nice clean or even NOS coil is a good unit, it can have hidden issues.

Greg Long