'03 90hp - intermittently won't start

Hello Everyone,

I'm having intermittent starting problem with 90hp yamaha and looking for any suggestions. Intermittently, when you turn the key, the gauges move, but does not crank. Sometimes, you can move the gear shift into and out of neutral, sometimes trimming the motor up/down a little, sometimes a prayer, will make it start??? The starting relay has been replaced. I have attempted to check with a meter and I believe the starter is good and I have 12V on one side of the starting relay when it would not crank. I am sure the neutral safety switch in the remote control assy is good. I just found out there is another neutral safety switch on the engine, (that's my next guess). I have been through wiring bundles and don't see any signs of corrosion. It seems as there have been a number of things that help for a day or two, then the problem comes back. Any thoughts or suggestions are appreciated.

Fred

[jb123]

may be a loose neutral switch in throttle box....which do you have , top or side mounted ?

hmm.. not sure what you mean about top or side mounted. I'm not much of a boat mechanic. There is a micro switch in the remote control assy, and I have check for loose connectors and with an ohm meter. It seems good. There is another neutral switch mounted on the side of engine (688-82540-11-00), and I'm not sure how to check that.

[jb123]

the switch in the control may be GOOD but in the wrong position can cause your issue...as could the gear switch on motor. the throttle switches are known to come loose occasionally.

ok, I'll take another look at the position and make sure it's tight.

Thanks,
Fred

[Dennisg]

why does everyone always look for the hard to do stuff. I had a very similar problem, went for new this, new that, new batteries, Etc., it turned out to be the key switch. Sometimes it would work, other times It acted as if the battery was dead. There are so many different symptoms that a bad igniton switch imaitates. If you are not 100% sure that it is good, test it, then replace if necessary.
Hope this helps, Dennis

Hello Dennis,

I have thought about this and tried to check. My dealer told me they didn't think that would be the problem because they have not had to replace that 'style'... Although they haven't been much help in fixing this problem either.

Thanks for the info,
Fred

[boats.net]

I have had a lot of trouble with the neutral saftey switch on shift linkage on motor(the 90 does use 2 neutral switches), the metal tab on switch will get bent out of position.

Thanks for the info. I'm on vacation this week, and the last two times out it has started every time.

Fred

[Bobber]

2nd Neutral swithc in 90

I have had a lot of trouble with the neutral saftey switch on shift linkage on motor(the 90 does use 2 neutral switches), the metal tab on switch will get bent out of position.

I recentely encountered this problem. I bypassed this second switch, as it is redundant, and my control box switch works fine and it is Normally open and closed in neutral so it should keep the engine diasabled if the switch failed. Am I wrong and should I replace this poorly engineered device? The metal tab does catch and gets bent up. My switch head aslo got its tip nippled off.

[bikecntr]

I had the same problem with my 60hp. I finally figured out that the battery cables were bad, even though they didn't have no corrosion, voltage and resistance was good, and they looked new. I had all the right voltage at the solenoids and tested everything.

I had a remote stater, which it is 2wires connected to a thumb switch. I connected the one wire to the positive terminal of the battery, and then connected the other end to the positive terminal of the stater solenoid. I pressed the button, and then turned the key switch on like regular and the engine started up instantly. All that you are doing is just taking the bad cable out the loop.

I had the same problems with the trim and the stater, and I thought it was a loose wire or ground, but all it was the battery cable. Good luck!

[robert graham]

Maybe the main ground connection on motor, corrosion on inside of battery cables. You need to remove, check, clean every connection, can't tell by just looking at it. Check/clean connection on side of starter. Your problem sounds like a bad wire/cable/connection. Good Luck!