Maybe a weak spark

[Usnguenther23]

Alright been fighting with this 1971 Plymouth Satellite for a few years but finally hit a shore duty(Navy) and want to get on the road.

I have completely rewired my car, neutral override switch bypasses/grounded. I can crank the motor right over, I rebuilt the Carb incorrectly at first but second try worked well as far as I can tell. Also new fuel pump. SO i am sitting here with fuel and crank, Last i know is spark. I did the old take out a spark plug and crank the motor over and it seemed to spark weak possibly and inconsistent. So before I buy a new distributor, spark plug wires, and coil. How can I diagnose these things? Coil and spark plugs are new.

Also does anyone have good learning information for Distributor Vacuum advance? I really don't even know what its for? Likewise with the other vacuum lines that come off the 4 barrel edlebrock carb?

 

[F4R/T]

First I would obtain a factory service manual, next check for voltage drop thru the feed to the coil . I’m not sure of the spec but low voltage is bad, just as bad as grounds. I’m not sure which ignition system you have but it’s pretty simple, you will need a good kline or fluke or very reliable multimeter. Take your time, electricity is just like water it will take the path of least resistance. If you do have electronic mopar ignition, check your voltage to the pins and make sure the box is grounded well, it’s okay to use temp jumper wires while doing this. Power and ground is the key..Don’t use Chinese parts or you will be chasing your tail or walking! Vintage USA parts are good !!! Work thru one system at a time, leave the vac advance alone till you figure out why your spark is weak, then proceed on.