1961 Chevy Bel Air hard starting

JAY MORRISSEY

MEMBER
1961 CHEVROLET BEL AIR

Electrical problem
1961 Chevy Bel Air V8 Two Wheel Drive Automatic

1957 chevy- 350 CI 400 hp- MSD 6AL ignition- mallory distributor and coil

My problem is when starting. When sitting and not running I have 12.2-12.5 volts from battery. As starter is engaged, voltage drops to aprox 9.5 volts and if I turn key to run real fast the engine will catch and run but only after several tries. I have tried a larger amp (725) battery. I have run all new oversized (2/0) battery cables and made sure all points of contact are clean and tight. I was told by MSD that if voltage on the small red wire (from ignition switch) drops below 10 volts, it will not start. I am prepared to do whatever is necessary (including a new ignition) but don't want to keep wasting time and money on the fix. Please help me as I'm going nuts. By the way. This is something that happened after a few years of weekend driving with no problems.

1 Reply

PIKAPART

MEMBER
12 POSTS

Had some one just 2 days ago with same basic problem. The switch its self gives right much trouble, you would think that because it is showing 12volts in run that it is not the problem but they get dead spots in them. Not sure if you have tried running a direct 12volt wire to the msd, bypassing the switch, be sure to put a fuse in line just to be safe, if it runs then replace switch, get a good one there are cheep ones but they are the ones that give the most trouble.
The only thing else that I can think of is that if it is run through a ballast resister that will drop the voltage as you described but if it had been running and nothing was changed then best guess is switch.