Working on a Yamaha Waverunner. Battery is charged, but key on stays dead. Ran the test light from pos battery terminal to the removed negative cable, nothing. Traced the negative cable to the starter bolt that holds it on, very difficult to get to. No corrosion noted. I thought I'll just cut it, put a new end on it and bolt it to the exhaust manifold. Problem is I can't get the test light to light up when I touch any bolt or the block, or the exhaust manifold. It lights when I touch the negative battery terminal. I'm confused. Can anybody shoot me straight on this. I thought it would light when I touched any metal on the motor, meaning I could use any bolt for the ground. Thanks for your input guys.