Re: Complete '73 Johnson 50hp...$50
I've got a few minutes to kill...
Please verify your battery. Pull the one out of your car if you need to, but the battery must have 12.6 volts and not drop below 11.0 volts while cranking. You can't diagnose without a known good starting point. Ask me about the $5,000 Escape repair due to a bad battery.
1) Verify the starter motor; Using jumper cables hooked directly on the starter positive terminal & engine block. Connect negative cable to the known-good battery. Firmly press your positive jumper cable end to the positive terminal to complete the circuit. There'll be a little spark of course, so protect yourself as you see fit with glasses and gloves.
Does the engine crank properly? Yes; proceed below. No; you're likely looking at a starter problem. Remove it and find a rebuilder who can test it for you.
2) Verify the short lead cable by hooking the jumper cables to the power "out" side of the solenoid, and the engine block. Connect ground lead to battery, then firmly press the positive lead to the positive terminal of the battery.
Does the engine crank properly? Yes; proceed below. No; the short cable between the starter solenoid and the starter motor is suspect. You can hook your jumper cable from the starter positive over to the solenoid "out", effectively giving the electricity a second path, and try to crank with key. If proper cranking is restored, replace the short cable.
3) Verify the solenoid function. Move your positive jumper cable to the "in" side of the solenoid. Attach ground jumper cable to the engine block Attach the ground and positive cables to the battery. Crank engine using the key.
Does the engine crank properly? Yes; proceed below. No; Your starter solenoid is suspect. Use your cables to bypass the solenoid by going from the "in" and "out" posts directly. This will spark, and the motor will jump, so be ready for this. If the engine turns over properly with the solenoid bypassed, replace your solenoid.
4) Reconnect the battery to the original wiring for the engine. Verify the engine still turns over slowly when cranked with the key. Use your jumper cables to connect battery ground to engine block, and crank it again.
Does the engine crank properly? Yes; The ground cable from the battery to the engine is faulty. Replace the cable. No; proceed below
5) With the original wiring still connected, use the jumper cables to connect battery positive to the starter "in" post. Crank with key.
Does the engine crank properly? Yes; The positive cable from the battery to the engine is faulty. Replace the cable. No; Gremlins.
