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Starter cranking when key is in run position

waterboy

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"Hi, new to site and new to in

"Hi, new to site and new to inboard motors. Have a 1978 Century with an 898 - 305 mercruiser with an alpha1 drive. When I turn the key, before I turn it to start, I hear the starter click and after about a 5 second delay the starter starts to crank. It's not engaging the flywheel on the motor either - justs cranks and grinds until I turn the key off. Any thoughts?"
 
"If you just got the boat, you

"If you just got the boat, you'll need to check the wiring to the starter solenoid and ignition switch. You should have a yellow wire with red tracer going to the solenoid for cranking. On the ignition switch, you may have two terminals that are loose and/or touching.

However, if the starter spins and doesn't engage, you need to replace it or have it rebuilt. Coast Guard regs don't allow car/truck starters or alternators in boats so make sure that the replacement is built to CG spec. While you're at it, check the battery posts/clamps, the point on the motor where the battery negative os attached, and if you look on/near the motor, there is a main wiring harness- separate the motor side form the boat side and make sure there's not a bunch of stuff between the pins that can conduct current or cause corrosion. Also, make sure it's plugged together correctly- there should be a way to index the two ends."
 
"Thanks Jim. Followed your in

"Thanks Jim. Followed your instructs, everything seems to be fine - no major corrosion, wires match up. How about the relay? My manual doesn't really show how the wires should be sent to the relay. Also, now that I disconnected and reconnected the battery, I can turn the key and the starter doesn't crank - niether in the run position nor the start position. Recommend a new ignition switch?"
 
"If you have a test light or m

"If you have a test light or multi-meter, check the voltage to the wires at the starter and also at the switch. One thing that's never mentioned in the manuals (I've never seen it, anyway) is that the starter is grounded through the bolts that holt it on and the mating surface to the block. Remove the starter (after removing the cables from the battery) and clean these surfaces and the bolts. If there are two small posts on the solenoid and you used one of them with no crank, move the yellow wire to the other small post. You may have a break on one of the wires in that circuit. Wiggle the ends and if they come off (not unlikely), replace it with the same kind. Crimp AND solder the terminals for durability and reliability. If you strip the insulation back and the wire is corroded (dark, not copper colored), clean it or find clean copper. You can't solder dirty wire.

The solenoid has definite input and output posts. The metal tabs also need to be grounded if it's not mounted on the starter. The battery cable needs to go on the right post- if the crank wire (yellow/red or yellow/black) doesn't work and you have a spare post that the ring terminal fits on, try that one. If one of the large posts spun when you tightened the cable on that post, the solenoid needs to be replaced."
 
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