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Starter help - 77 R107 450 SL

548 Views 4 Replies 5 Participants Last post by  RaceDiagnostics
I am befuddled with my starter issue. I have a new starter that I bench tested with existing my battery. It worked fine which is expected with a new starter/solinoid. I attached the car's wires to the new starter but did not fasten to the engine/flywheel. Tested with a voltage tester, I have power to the starter and solinoid when the key is turned. Power to solinoid is off when key is turned off. I go to turn the ignition on and nothing. I first thought since the starter is not touching the engine, it wouldn't have a ground. So I connected a ground jumper from the engine frame ground to the starter. Still nothing. Relay is turning on (clicking) when I turn the key. I even replaced the ignition switch as I thought that no could have been the issue. Unscrewed that and turned the ignition switch with a flat head screwdriver and still nothing. I even used a jumper wire from battery positive wire to starter positive post and it turns on so I know the starter works but not with the car wiring. But that is completely bypassing the solinoid. Any help would be greatly appreciated.

Update : I switched the relay with another relay with the same rating. Same problem.
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The two smaller wires are different sizes, and have different size ring terminals on them, and the starter terminals they connect to use different size screws. This makes it difficult to connect them wrong...UNLESS someone at one time cut the ring terminals off and replaced them with different sizes. So look closely at those two little wires, and the terminals on them, and the colors of the wires. Take your time.
Check your neutral safety switch - ask me how I know!
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