hokie04

I have a 64 327 300hp with Mallory unilite system in distributor. I just reinstalled my cluster and had the ignition in the on position checking lights, wipers, etc. I happen to touch the ballast resistior and it was real hot. I have read many threads saying that is normal.

My question is the resistor is suppose to be 1.8 - 2.2 ohms. When I checked mine it was 5.0 ohms is acceptable or should I replace it?

The current wiring setup is the pink wire to coil on one end and the ign on the other. The pink wire from the mallory unilite is on the coil with the other pink wire instead of going to the ballast resistor. Shouldn't be on the ignition side of the ballast reisistor?

buns

Mallory suggests you can use your original resistor, or their Part # 700, which is rated at .75 to 1.5 ohms. Standard Brands has the one you want.


I took their wiring diagram and "tinkered" with it, so it is right for midyear Corvettes:











Note: Where I have noted the wires as 'pink', they may be black with a pink tracer. '64 and '65 I believe.

62Jeff

Awesome effort Buns, as usual.

hokie04

Awesome diagram! I thought from looking at the wiring the previous owner had bypassed the resistor. I will rewire accordingly. It sounds like I should buy a new resistor since the old one is reading higher ohms then spec. You mentioned Standard Brands who sells them? Thanks!

landshark 454

A note on the Mallory Unilite system... Do not disconnect the coil wire or any plug wire while the engine is running or cranking. This will cause a failure of the sensing light in the distributor, and cost you around $100.00 to fix. I have seen this happen at least 4 times. Do not crank unless any disconnected secondary wire is grounded. Failure is usually immediate, and pretty much guaranteed.

hokie04

Thanks for the information I will remember. I think the unit I have is over 20 yrs so I don't know the life of these units.

I am going to order a new ballast resistor since I dropped it and a chunk of the bakelite that goes the the wire windings fell out. I am getting a ohm reading of 5 ohms so I think it will be ok until the new one arrives.

rgs

Did you measure the resistance with the ballast cold? As it warms up the resistance value increases.

hokie04

You are right I measured it warm and it was 5 ohms. I measured the next day and it was just a little over 3 ohms. I had dropped the resistor and the bakelite stuff inside the wire winding started crumbling I am sure that didn't help it any. I ordered a new one.