2012 Yamaha F40 dead...won't start power trim dead too.

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SquiggyFreud

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Hey all,

Went fishing yesterday boat ran great all day. Returned home, attached ear muffs to motor to flush it out. Would not start, no power, nothing but an occasional clicking sound. Power trim not working on remote or side of engine either. Digital tach would come on but dim and go off when turning key to start. Accessories worked but are on separate connection to same battery.

Connected trolling battery to engine, same thing, no power. Trolling battery had been used for about 4 hours so I thought it might just be too low to crank.

Ran battery to auto-zone this morning...bad battery, purchased a new one, took it home and connected to engine.

Trim worked, engine started to crank but since I had not reconnected water I turned it off. Trimmed up and down once or twice. Put everything back where it belonged and went inside to eat breakfast.

Pulled out boat to flush engine...holy crap same issue! Occasional clicking sound, no power no start, no power trim. Digital tach would come on but dim and go off when turning key to start.

Grabbed multimeter. 12.36 volts at battery. turn on key 12.34v at battery turn key to start 12.33v at battery.

Voltage at engine where battery cables connect to engine 12.36v. Turn on key, voltage drops to 8.4 volts, turn key to start drops to 4.? volts.

I did check fuses by the way.

Any thoughts on the issue?
 
Ooops my bad......I do see your title now. (sorry)

2012 Yamaha F40.

Low voltage is pointing to a bad alternator draining your battery. Or possibly a ground.

Have you added any electrical equipment lately like a radio or depth finder? Could be something so simple as a wire in the back on newly added equipment is grounding.

Newer motors don't like low voltage (neither does my Harley). They flat will not run on low voltage.
 
SquiggyFreud said:
Grabbed multimeter. 12.36 volts at battery. turn on key 12.34v at battery turn key to start 12.33v at battery.

Voltage at engine where battery cables connect to engine 12.36v. Turn on key, voltage drops to 8.4 volts, turn key to start drops to 4.? volts.

connection issue either at the battery or perhaps at the engine somewhere. Dead giveaway "turn key to start drops to 4.? volts."

Or....less likely....engine locked somehow. Remove the flywheel cover and see if it will turn by hand. That will eliminate that. Can't remember the last time I had an issue with an F40-other than fuel related (old fuel). The thought crossed my mind about a dead brand new battery but measuring voltage AT the battery and very little voltage drop kind of eliminated that thought.

Also possible that the factory battery cable may have some corrosion inside of the insulation. I would look at the battery side of the wires-expecially if it's been near or in salt water.
 
I plugged the battery into the charger last night... it did charge for a couple of hours before showing fully charged. I guess I assumed a new battery would be ready to go...will try it out when I get home...thanks for the responses so far.
 
turbotodd said:
SquiggyFreud said:
Grabbed multimeter. 12.36 volts at battery. turn on key 12.34v at battery turn key to start 12.33v at battery.

Voltage at engine where battery cables connect to engine 12.36v. Turn on key, voltage drops to 8.4 volts, turn key to start drops to 4.? volts.

connection issue either at the battery or perhaps at the engine somewhere. Dead giveaway "turn key to start drops to 4.? volts."

Or....less likely....engine locked somehow. Remove the flywheel cover and see if it will turn by hand. That will eliminate that. Can't remember the last time I had an issue with an F40-other than fuel related (old fuel). The thought crossed my mind about a dead brand new battery but measuring voltage AT the battery and very little voltage drop kind of eliminated that thought.

Also possible that the factory battery cable may have some corrosion inside of the insulation. I would look at the battery side of the wires-expecially if it's been near or in salt water.


Not locked...I can attach cord to engine and pull, and it did turn over initially each time I reconnected battery.Yes it has been around salt, but kept in a battery box and also stored under carport. connections look nice and clean.

To answer Lone star above...no new accessories, same equipment connected for 2 years.



Tried it out this afternoon. I had it disconnected to charge...trim worked engine turned over. Waited a few minutes dead again. Voltage today reads 12.8v as opposed to 12.36v from yesterday. Otherwise like a broken record.
 
Issue resolved...loose battery cable on starter. should have checked it sooner, but it is what it is...I am thrilled it was something simple.

Thanks for your input all.
 
IOW, when the motor was rigged-probably at the dealership-the battery cables were not torqued. Or the wrong hardware used. Not surprising considering the assembly instructions are written in japanenglish. That's the only complaint I have with Yamaha.
 
turbotodd said:
IOW, when the motor was rigged-probably at the dealership-the battery cables were not torqued. Or the wrong hardware used. Not surprising considering the assembly instructions are written in japanenglish. That's the only complaint I have with Yamaha.

Again I am glad it was simple...as many times as I put the multimeter on the screw, surprised I did not notice it was loose.
 

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