Yamaha 90 Hp 2 Stroke Trouble? (Fixed, Thanks All)

[JohnP]

This past wednesday on Bull Shoals while running up the lake heading back to the ramp after fishing, about 3 miles from the ramp and into a strong head wind the motor starts cutting out, but not dying, at full throttle. Back it down to the 3/4 throttle and it ran fine. Go back up to full throttle and it starts cutting out again, went back down to 1/2 - 3/4 throttle. Made it back to the ramp and go to put the boat on the trailer and it won't start, no power when turning the key???? Check all connections, kill switch, make sure it's in neutral, and fuses and everything seem fine, power to all the accesories and tilt and trim works but nothing to motor when turning the key. May be the ingnition switch but would that cause the motor to cut out at full throttle? Thinking possibly power pack but would that cause there to be no power to the motor from ignition??? Also checked the fuel line connections, primer bulb, and vent on the tank and everything was in check like it should be. Motor is approximately 6 years old.

Also can anyone recommend a good and reasonable outboard motor mechanic incase this is something more than I can fix?

Thanks,

John

[fishinwrench]

Don't know if you have a voltmeter on the dash but if you do did you notice any voltage spikes (Over 14.5) or irregular tachometer readings?

Sounds like a voltage regulator failure, probably caused from a bad battery or loose/dirty connection. Peek under the flywheel and see if the stator windings and voltage regulator (and associated wiring) look like they've been hot.

[JohnP]

the boat is a 1860 g3 with a 2 stroke 90 hp tlrc yamaha. Motor is a 03 model. very basic set up, no instrument panel . side mount 703 remote control box. Pulled the ignition switch out and check all the connections to make sure nothing broke loose or pulled apart, and then put a 12 volt light tester on it to check for power. Have power to the switch with the red wire, turn the key one click and have power with thru the yellow wire and I believe the green but can't remember right off hand, checked the blue and white wires and no power with the key in any position. No power going to the throttle relay switch from the brown wires . Thinking that the switch might be bad???? But I'm not a expert by anymeans.

[fishinwrench]

Did you charge the battery, and clean and tighten your battery connections ?

And is your choke working? If not check the fuse or breaker on the motor. Then check to see if there is 12v to the starter solenoid from the ignition switch (green wire I think) when the key is turned to start. Could be a neutral safety switch bad but that isnt going to be the cause of the original problem ( 3000 rpm stall).

[laker67]

This is a really great aspect of this forum. Not only wrench, but several others are always there to offer assistance, or advice or even directions to their favorite fishing hole. Thank you forum members.

[JohnP]

Did you charge the battery, and clean and tighten your battery connections ?

And is your choke working? If not check the fuse or breaker on the motor. Then check to see if there is 12v to the starter solenoid from the ignition switch (green wire I think) when the key is turned to start. Could be a neutral safety switch bad but that isnt going to be the cause of the original problem ( 3000 rpm stall).

Checked the battery, removed and cleaned all connections, and changed the fuse that's under the cowling even tho it appeared to not be burned out. No power to the neutral switch so don't think it's that just yet. Want to say there was no power out of the green wire but if there is then are you saying I need to trace it to the solenoind? Chokes not working that I can tell, push in and nothing that I can see or hear around the carbs.

[fishinwrench]

Ahh, ok, now we are getting somewhere.

So you have 12v at the ignition switch, correct?

Now check to see if you have 12v leaving the switch on the crank and choke terminals. (Wire color for reference can be confirmed by looking at the starter solenoid and the choke/primer solenoid)

[fishinwrench]

Here's your harness color code chart...

http://www.maxrules.com/fixyamahawiring.html

[JohnP]

Thanks wrench. Hoping that will fix it at least so I can get it started and then work on the loss of power issue.

[JohnP]

Red: power (check)

Black: ground (check)

Yellow: key turned to power on (check)

Blue: choke, power on when pushed (check)

Brown: neutral switch power on when key turned to start (check)

White: ignition stop circuit ( no power????) should there be power coming from the ignition switch to the kill switch, would think so. If so would it be a bad ignition switch or kill switch. kill switch is snapped in to proper position.

Green wire comes in and is capped off. (no power to it?)

Thanks again for the help and suggestions.