Start and Ignition Problems on 71 Demon

I don't remember, 71 didn't have any seat belt interlocks, did it?

I'd get into the ign switch connector where it comes down the column. You might need to remove the 2 screws and trim under the column.

You have a shop manual, wiring diagram?

Usable diagrams here:

http://www.mymopar.com/downloads/1971/71DartA.JPG

http://www.mymopar.com/downloads/1971/71DartB.JPG

which came from here

http://www.mymopar.com/index.php?pid=31

Look at diagram "B" and find the ignition switch connector

I do not believe these are in order on the connector, probably same as the '72 connector

Yellow goes directly from the IGN sw through the bulkhead to the start relay, UNLESS the thing has a seat belt interlock and is hot ONLY in "start"

Brown goes directly from the IGN sw through the bulkhead to the coil + side of the ballast resistor, and is hot ONLY in start. The yellow and brown are isolated from each other

The dark blue goes from the IGN switch and is UN fused, and feeds the warning lights and gauges (cluster voltage limiter.) It "tees" off and goes through the bulkhead, and feeds the alternator field, the regulator "I" terminal, and the ignition system. It is hot ONLY in run NOT in start

So check those three at the ign switch connector, chase them through the bulkhead. Probably a good idea to pull the bulkhead connector sections apart and inspect them

Do the gauges/ oil warning light work?