twintracks

I've got a weird one, and could use some guidance, especially if someone has had this happen.
'64 Olds 98 394. Engine was replaced by the previous owner.
The car seems to have no spark when the key is turned to the starting position. If I release the key at the right moment, the car will roar to life.
It's like there is some grounding fault when the key is in the start position, that goes away when the key is released to the run position.
Obviously, this is not right, and makes it very hard to start the car.
Any ideas??

MDchanic

Easy: In general, either the connection between the starter solenoid R terminal and the coil (+) terminal is not complete, or you have a problem with the Ignition switch contacts in the Start position.

Exact starting and running circuit wiring changed a few times in the early sixties, but in the case of the '64 fullsize, there should be no solenoid-to-coil connection, the ignition switch has two separate wires to the starter, Yellow for Run (through the ballast resistor), and Black for Start.

IF the car is wired as original, you have either a problem with your ignition switch or a break in the black wire.

IF the wiring was changed over the years, with engine changes, etc., then the other possibilities apply.

- Eric

twintracks

Thanks Eric.
I think I can get this, but I'm not there yet. I think I have option B from your posting.
It will be all stock when I shut the hood. I'm going to blame the ignition switch last. It's a California car, with everything under the dash looking good.
The ballast resistor is there, but it is not connected, not wired. I know what it looks like, but not how it should be wired.
Can you give the basics there?
Also, the R Terminal you mentioned; is that on the starter or the ignition switch?
Many thanks,
Jerry

oldcutlass

There should have been 2 wires on the load side of the ballast resister, a black to coil +, and a black that runs from terminal 2 off the ignition switch (the bypass wire for start). On the power side of the ballast resister, there should be a yellow wire from terminal 1 off the ignition switch (run wire).

If you don't have a ballast resistor then there is a yellow resistance wire from the terminal 1 on the ignition switch (run wire) to the coil+ and black bypass wire from terminal 2 off the ignition switch (bypass wire for start)

MDchanic

There should be a yellow wire that goes from the ignition switch to one side if the ballast resistor, and then another yellow wire from the other side of the ballast resistor to the coil (+) terminal.

There should be a black wire that goes right from the ignition switch to the coil (+) terminal.

In cars from a year or so later, the starter solenoid has two terminals, an R and an S, but your car should have only one, an S. I only mentioned that because sometimes changes are made over 50 years, and someone might have put in a later setup.
If it's original, it won't have that.

- Eric

twintracks

OK, I just took another look.
What I have is a brown wire connected to the (+) on the coil, and a black wire not connected to anything, just cut off. Both coming out of the wiring loom in the right place.
The ballast resistor is there, and seems in good condition, but also not connected.
I cannot find a yellow wire.
(-) on the coil is connected to the distributor.

oldcutlass

Check to see if the black wire has 12v with the key in the start and run position. Check to see if the wire connected to the coil + has 12v in the start and run position. Are you still running points or an electronic conversion?

twintracks

Thanks other Eric,
I've got 4 volts from the brown wire, and nothing from the black wire in the run position. I tested the black wire, and it is not grounded, at least not in the run position. I cannot test the start position until my son gets home from school.
It's a points ignition. 12.94 volts at the battery, which is a new battery.
What is the purpose of the ballast resistor?

MDchanic

The black wire should show +12V with the ignition switch in the Start position, but not in the Run position.

The ballast resistor serves two purposes:
1. It serves to help tune the resistive / inductive / capacitive (RLC) circuit of the points, coil, and condenser, by varying its resistance with the load applied, which also corresponds to the frequency of impulses through the coil - the ballast resistor's resistance changes with its temperature, so as the load (and the frequency) increase, the resistor gets hotter, and its resistance increases.
2. By making the coil run ideally on about 9 volts, you assure that the engine will start while cranking, even if the battery is low, by providing a non-resistive path to the coil while cranking.

- Eric

oldcutlass

I was under the impression that your car has a resistance wire not a ballast resistor. Maybe others with knowledge of your vintage can help. In order for your points ignition system to function properly you need one or the other. So I'm hesitant to tell you to hook it back up.

rocketraider

Based on personal experience with numerous 63-66 big Oldsmobiles- ignition switch. I'd be willing to bet you'll also find some melting on your ignition switch connector.

twintracks

Thanks folks!! I think I got it by rereading everyone's posts. I wired the black wire to the coil (+), and ran the brown wire to the ballast resistor. Then ran a new wire from the other side of the BR to the coil (+). It started properly after that.
As soon as I got it started however, I had a flooding carb, and then had to quit for the day.
Back at it tomorrow...
Thanks!!

oldcutlass

Make sure when the engine is running that you have around 9v at coil+.

twintracks

Voltage at the coil is fluctuating between 5 and 8 volts at idle.
Running and starting very well.
Thanks!