Had the same problem. Wouldn't start when hot like the battery had gone flat. My ground cable went from the battery to the frame and then to the block. This cable was a bit on the light side. I ran a new and much heavier cable from the battery direct to the block, problem solved.
Regards,
Bryan
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COB-66 Young at heart old fart.
Don't drive faster than your guardian angel can fly.
If it doesn't matter what gear your in you have enough torque.
VK3KDN
