Trouble starting up after the rain - 2009 Yamaha C3

[mrsamsonite]

Hello all,

I've got a very consistent problem that I'm trying to troubleshoot, as it's happened four times now. I have a 2009 Yamaha C3 that normally starts up no problem (electric or kickstart). I run into trouble when I try to start it after rains.

First, the electric start won't work - the engine will turn over but that's it. The kickstart (which normally works on the first try) typically takes about 3 or 4 tries to start up. I'll then be able to ride the scooter for about 2 or 3 minutes, but the engine typically cuts off once I come to my first stop. One time, it cut off while I was in motion. Each time this happens, it takes another 3-4 tries to kickstart it and get it running again. After that, it runs with no problems until the next rain. 

Any thoughts on what would cause this specific behavior? I assume rain water is getting somewhere it shouldn't, and I do live in a pretty windy area which could aid that (I've had this happen even when I had the scooter covered in the rain once). 

[spaz12]

Welcome to the forum

Possibly you are getting moisture in the CDI? I was thinking maybe in the kill switch as well?

[Senna1Rossi]

seems electrical in nature...

Dang. can't believe you have a Cube... Lucky.

you need to post up pics, mate

[FrankenMech]

It may be dirt or salt on the outside of the plug shorting it out when wet. The same thing can happen to the coil HV connection. Cracks in the coil wire can cause the same problem. Most of the time once a component has been compromised by an arc of this type there are little tracks from the arcing left behind. Those arc tracks are permanently burned into the surface. Replacement is required.


EDIT- Moisture helps the tracks to become conductive. Once the part warms up and drives off the moisture, or the arcs heat up the surface to dry it up, then the component may 'work' for a while. Every time it arcs the voltage it takes to jump the burned area goes down usually due to carbon tracking.

When a new plug or coil is installed make sure the surfaces are clean then apply silicone dielectric grease to keep water out.

[greggkinney]

I'm an avid mud slinging, rock crawling, water over the hood up in the seat with you kind of off roader. Trucks, jeeps and 4 wheelers. I always spray ALL my electronic components with camp-dri brand silicone spray. Its been safe on all my switches, ecu/ecm's, sensors, keyswitches, ballast, wires, solenoids, coil, caps, i mean literally everything electrical. Even down into where the wiring goes inside of the plug ins. I pack the wiring plugs with Vaseline sometimes and the plugs that go into the ecu's too, to seal water out. Permatex works too or the vaseline on the seams of ecu. Anyways what I'm getting at is its safe and works on my trucks so I've sealed my scooter in the same manner and its seemed to work, Its at least not hurt anything and if nothing else all your stuff will be shiny. So spray that cdi, coil, and switches

[larrball]

Frist off Welcome to the form.


4T that's fuel-injected/Water cooled. (i hope this doesn't go ECM)

Not that this matters but i had a few scooters that did the same. to find out the dam spark plug wire was lose.
Nope, it looked good to go tell i played with it and .. darn. i pushed it back on--

Replace the spark plug. <-- never hurts (the pocket book to replace one) and is about time,yes?

Then put on a new CDI (order now or it wont get hear tell X-mas)




Alsome scooter