Strange electrical problems.... 48 New Yorker

[Guest chieflander]

It never rains, but pours. In the wake of the relay fiasco, I am now suffering from a rather odd clicking noise that occurs just after you start the car, (1948 Chrysler) and doesn't stop. Now, I have determined the proximate location for the noise to be around the generator. There was an errant wire dangling down there, that connected to nothing, so I taped it off. Same problem. Then, there were wires touching on the brake light switch, so I taped them up. Same problem. Then, I tightened a point on the generator itself. Same problem. I lubed the generator, same problem... As if I weren't frustrated enough, I was driving along, and I put the lights on (it was raining) and viola! The noise stopped, or lessened. So, my first thought was a fray or arc in the wires leading to the headlights. Nothing... So, a friend of mine said he felt that it may be the generator showing the first signs of failure. Any suggestions?

[Guest De Soto Frank]

When you hear this "ticking", watch the ammeter needle... if it is deflecting in synch with the "ticking", then there is either an intermittent short or a poor connection.

What I found to be a source of "noise" was the cut-out relay in the voltage regulator, which would occaisonally open & close, if the engine idle speed was "drifting" above & below the cut-out setting...

( Your mention of the problem "disappearing" when the headlights are switched-on, makes me think this does involve the VR and the cut-out opening & closing... make sure you have good grounds between the genny & block, regulator & firewall, firewall & block (you might need to make a jumper), and battery Positive and block. )

Also, sometimes the fluid-drive relay points would occasionally chatter, but I think this was when the contact hinge/spring was in the midst of failure...

I would take a systematic approach to this... check-out a given component (say the generator) and diagnose/evaluate it and either repair it & move on, or at least note what it's issues are...

The biggest problem with these pre-'55 MoPars (and many other makes) is the cloth-covered wiring that begins to shed its insulation about 25 years after the car was built... in the case of our NYer's (I have a '48 too), that process started about 30 years ago...

Another source of "ticking" in the vicinty of the generator could be loose mounting bolts that attach the genny to the block bracket... this can allow the genny to "wobble" and make noise...

Try removing the fan belt and running the engine, and see if the noise goes away...

Good luck - stick with it !