Yamaha 90HP won't turn over.

[stevenconley]

My engine is a 2002 Yamaha 90HP O.B. I had the water impeller replaced and they said they ran the motor to make sure it was pumping water. I brought the boat home and a month later took it out for a ride. I put the boat in the water and tried to start it, but it didn't even turn over. Stop lanyard was attached, battery fresh/strong charge (checked with multimeter), cleaned battery leads, checked fuses all the way into the engine. Multimeter reads power aft of the engine fuse with the key on. The starter has jumped to engage on 5 occasions out of 100 when moving the shifter lever from forward/reverse to neutral. Other than that, nothing. Now, I'm thinking it is something to do with the neutral switch. I checked all connections (secured), no corrosion on any connections. Everything looks like new. If they disconnected the battery wrong (red lead first), can it short out something? What am I looking at here? Thanks.

 

[rodbolt]

Re: Yamaha 90HP won't turn over.

hello<br /> sounds like a nutral start switch has failed. all engines/controls must have a safty switch to prevent start in gear.if the engine does not have it the controls do. most larger yammis have it in the cdontrols. look low on the stbd side of the motor. the solinoid that the battery positive cable goes to and the brown wire is the start solinoid. unplug the brown wire. test for 12 volts from the brown wire on the harbess not solinoid side to ground with the key in the start position. if you dont have the 12 volts I would suspect the start switch in the controls. do all testing with the emergency stop lanyard disconnected. you can use a jumper wire from the brown wire on the solinoid to 12+ and see if the solinoid engages.<br /> good luck and keep posting.<br /> PS<br /> if you hook up the battery backwards the engine 20 amp fuse pops.

 

[stevenconley]

Re: Yamaha 90HP won't turn over.

I did as instructed. The starter engaged when 12+ was applied to the silenoid side brown wire. After close inspection of the neutral switch in the engine, I found the control arm that depresses the switch was broken. Some crappy cast metal part. I found out the Yamaha 90 has a redundant neutral switch (one at the engine and one in the throttle box). The redundancy was due to demands from clients oversees. I just disconnected the brown wires from the neutral switch (at the engine) and plugged there mates in together at the silenoid. Whalla! Engine runs. I checked to see if the motor would start in gear and it doesn't. Thanks for all your help in diagnosing this problem. Your a great asset to the online boating community.

 

[31900]

Re: Yamaha 90HP won't turn over.

Rodbolt certainly is an asset but he did send me on a wild goose chase looking for a monkey that could fix Yammies and clean fish....

 

[rodbolt]

Re: Yamaha 90HP won't turn over.

wow<br /> and I thought you could find one.<br /> oh well there is always a cool frothy refresing beverage