Starter Issue

[Jtgator]

I have a 25 ft. CC with a 2002 Merc 250hp XL EFI O/B.
Turned key and just heard whining noise. Charged up both batteries . The starter was spinning but not engaging/ Had an xtra starter so I switched them out and still just spins but not engaging.
If the solenoid is bad would the starter spin at all? Also checked all wires and connections. Any advice is appreciated.

 

[JB]

Re: Starter Issue

You probably have some corrosion in the high current circuit for the starter, JT. Take both battery cables and the heavy cable from the solenoid to the starter off at both ends. Scrub all connectors shiny, check for weak or swollen spots, then reconnect.

Let us know the outcome, and good luck.

 

[Jtgator]

Re: Starter Issue

Thanks JB, I did clean all the connections from starter to battery. Could a bad solenoid not allow high enough voltage to pass through to the starter? Like instead of passing through 12 volts it only allows 10? I'm no means an electrical engineer.

 

[riptorn]

Re: Starter Issue

Mercruser(GM) should be same with O/B
It's not the solenoid or it would just click or not work at all. It's the starter drive, the gear in the front won't come forward or up to engage with the flywheel. Take the one you took out and spray the drive with WD40 or a few drops of oil and let sit for a while. (Don't get any spay into the starter windings) Apply power to see if the gear comes forward, if not just tap the gear lightly like your opening a jar of pickles. The part is pretty cheap but the labor, ouch.

 

[JB]

Re: Starter Issue

Thanks JB, I did clean all the connections from starter to battery. Could a bad solenoid not allow high enough voltage to pass through to the starter? Like instead of passing through 12 volts it only allows 10? I'm no means an electrical engineer.

Yes, it could be a corroded solenoid. Go to the Engine FAQs forum and do the starter circuit troubleshooting in "Outboard won't start".

Back to the cables. Did you take the ground cable off, too? Where it bolts to the engine block is the most common site for corrosion. You have a tinned copper terminal bolted to an alloy block with a steel bolt. That is a guaranteed site for corrosion and should be overhauled annually.

 

[CharlieB]

Re: Starter Issue

Simple test of the starter solenoid, grab your trust battery jumper cables, jump directly from the battery to the starter, if it turns faster than it does when the solenoid engages, replace the solenoid.

NOTE: This is assuming you have already follow all previous advise and have made SURE that ALL cable ends are clean bright and tight.

 

[Jtgator]

Re: Starter Issue

Problem solved. Both of the batteries were bad. I did not expect both batteries to go bad at the same time but anything is possble on a boat.