: intermittent ignition problem...yamaha 90 hp
07-22-2008, 05:53 PM
Been having an issue with my motor starting with the key. It is an intermittent problem in which at times, the motor will start by the key, then at other times I get nothing...not even a click. Battery is new, and all connections that I know of seem to be fine. All bolts, etc are tight for starter etc and clean contacts too..
I am able to start the motor with a cord and it will fire right up...so I am wondering if I may have a starter switch issue...but how would I check it?
Anyone run into this before or have any suggestions to check?
07-23-2008, 07:29 AM
One thing you might try is locate the starter solenoid on the engine,,,,it will have two smaller wires going to the solenoid coil and two larger wires which provide 12v to the starter when the coil engergizes. Clip voltmenter leads to the small wires (+to+, -to-) then try to start the engine. If you are getting 12v on the meter your switch and switch wiring is ok and you most likely have a problem with either the solenoid or starter. If you don't have 12v to the solenoid when trying to start the engine you have a problem with the switch, switch wiring or a bad connection. Try to do this when the starter switch appears to not be working. Let us know what you find out.
I wonder if you are having issues with your kill switch on the control box.
Sometimes, folks don't have the kill switch completely in the correct position and this results in an intermittent start condition.
As the other fellow suggested. Use a voltmeter for voltage on the solenoid. If, when turning the key, you have voltage at the ignition switch connection on the solenoid - the ignition switch and kill switch is all right. The problem is either the solenoid or starter. If you have voltage on the solenoid when you turn the key, but don't have any thing at the starter, use a jumper to jump directly to the starter. If the starter then starts the engine, the solenoid is bad.
If, when the starter is jumped directly from the battery, the starter doesn't spin - the starter itself is bad.
07-23-2008, 07:46 PM
An intermittent or loose Neutral/Start cutout switch could cause this.
On Yamaha,it is a plunger type switch that is activated by the gearshift linkage when the gearshift is in
NEUTRAL,allowing the electric start to operate. It is DEACTIVATED when the shifter is in Forward or Reverse,cutting out the starter circuit. If this switch either fails,or just loosens up from its mounting bracket and falls out of position so it cannot be operated by the shift linkage,it will cut out the starter circuit. Won't even get a click. If yours loosened up just a little, could be causing your intermittent failure.
Not sure where it is located on yours,but on the 40HP it is in the bellypan,buried under a wiring harness.
Take a look closely at your shift linkages,and trace the motion,you should be able to find and inspect it.
07-25-2008, 05:35 PM
That plunger has been one item I have considered too. Pretty easy to get at and with only two leads, easy to check. I am wondering if that is considered the starter relay that shows in the service diagram. I have not found any solenoid as of yet in the service manual, but I will be starting my checks at the starter and working backwards from there.
Thanks for some heads up on this!! Now...I just need the volt meter to get going on it and get the boat back in the water...next week!! I will report what I find, given the situation happens again (the one and ONLY time I would actually LIKE it to happen again)
07-27-2008, 12:33 AM
I had a very similar issue with my Yamaha F-115. After changing batteries and even the starter ( selenoid and starter motor), it continued to have the same intermittent problem. I noticed the problem was more pronounced when it was colder ( air temp). I finally solved the problem when I torqued down the wire terminals on the Battery. There was just enough resistance ( poor connection) that the starting motor selenoid would not engage. I'm still amazed at how voltage sensitive the yamaha starter selenoid is.
A procedure that works well for batteries and wiring is as follows:
1. Removed all wires from batteries terminals.
2. Use a mixture of baking soda etc. and wire brush to clean the terminals as well as the wiring connectors themselves.
3. Rinse and dry all of the connections.
4. Take common wheel bearing grease and completely coat the ends of the wires - up a bit on the wiring as well as a liberal coating on the battery terminals.
5. Put the wires on the battery terminals, use a wrench to securely tighten the wiring connections.
6. Apply some more grease over the tops of the nuts and wires.
The idea of the grease is to provide an air tight, watertight coating on the wiring and battery terminals. Once the connections are clean and tight, the grease will keep them free of corrosion and bad connections. When you tighten down the connections; you will displace any grease between the metal of the battery post and the wire ring. The added grease will enhance the moisture resistance.
A bit messy, but inexpensive and very reliable.
If you like, you can use silicone grease, which is clear and just as effective - if you happen to have a can or tube of silicone grease.
Remeber - use a wrench to tighten all battery connections. Do not rely on finger pressure to get the nuts tight.
07-29-2008, 08:57 AM
[QUOTE=VMS Steve;1045194]That plunger has been one item I have considered too. Pretty easy to get at and with only two leads, easy to check. I am wondering if that is considered the starter relay that shows in the service diagram. I have not found any solenoid as of yet in the service manual, but I will be starting my checks at the starter and working backwards from there.
NO,that is not the starter relay. The relay would probably be in close proximity to the starter motor itself,with leads going into the wiring harness as well as rather large leads to the starter motor itself.
Go to this Yamaha parts lookup site, find your year and model, look in "Electrical" to help you ID the relay:
A quick check of the starter motor can be done by just jumpering across the relay and see if the motor spins. WARNING: !!! Make sure your safety lanyard switch is pulled OFF so the motor does not start up. The safety lanyard off will disable the spark,but will not effect the starter motor, enabling you to run tests on it.
Good luck..because " intermittent" problems can sometimes be a bear to find ! Let us know how it turns out.