Voltage drop at HEI in "crank"

[eric8]

Originally Posted by Dead Parrot

I never saw a mention of it being hard to start, just an interest in voltage drop. IS the thing having starting problems?

My suggestions on order of things to replace if needed:
1. Battery cables. Old but nice looking cables can be rotted on the inside.
2. Have the battery tested. It may be good.
3. Have the alternator tested. Low battery issues can be due to lack of good charge.
4. Only if needed, replace battery. No point in spending $100+ if not needed.

Never any issues of hard starting. Just discovered this during some troubleshooting after a couple of fried HEI modules. I was getting low voltage at the distributor during cranking. Performance Distrubutors gave me their troubleshooting guide which said I needed at least 10.5 at the distrubutor wire during cranking or else it's hard on modules.

I will look at having the battery/alternator tested and check the ignition column switch. The reading of 10.2 volts was directly at the battery terminal bolts during cranking was taken after a full overnight charge.