Water getting into one of the spark plug holes

[roy]

I changed my plugs at 13,035 miles this past weekend. It's never been cracked open. My inboard plug on the #1 cylinder was corroded bad due to water getting in the hole I assume from the coil over cap failing to keep it out. It was damp in the hole but I washed the bike the day before plus rode in a down pour while out on a recent trip. I didn't pay close attention upon removing the coil over but recall it seemed at snug as the others. It's been leaking a while due to the extensive corrosion on the plug metal which was rusted badly. It's pure water no coolant. I can tell the difference. I am pretty sure it's coming in from the coil over cap. I probably won't go checking again until plugs are due again it's a pain in the but to just get at them.

Anyone else had this happen ? I know on suzukis they have a small hole driiled through the head for drainage no such hole on the Yamaha.

 

[Yamaguy55]

My WRR leaks as well, but it at least has a drain hole. I see no drains on the Tenere, and figured this would become a topic. Perhaps a small amount of silicone grease on the sealing portion of the COP and also in the pat where the plug inserts into the COP would help. If nothing else, it would reduce corrosion. My F150 is the same way, and whatever water gets in there has to boil out when the engine is running.

Maybe they wanted water cooled coils and plugs? >

 

[roy]

Well the water that was in there should have burned off but it all didn't for some reason or another. Granted it was not a long ride that morning after the wash job the afternoon before. Dry at plug but moist and wet on walls of the hole up near the top. Same dampness on coil over near top. You can see some corrosion in that location on coil over. I air dried the hole with compressed air then took out old plug before installing new plug. Old plug came out fine just badly corroded. So I assume the hole filled up with water on the wash job then slowly steamed off on my short ride that morning. I may just keep an eye on it and not spray direct water up over the head on washings. I drench it pretty good on bath day. The cap snapped on like the others so maybe it just wasn't on good to begin with.

 

[EJV]

Yup. Been there. Done that. Mud is better.
I had to scrape the "dried mud" and dirt, then blow it all out before removing the Spark Plug.
It took a while to clean up the Coil Stick too.

New plugs now.

 

[DcN]

Yeah, same problem with same plug when I wanted to fog cylinders for winter storeage last fall. I could only think I must have washed the bike and then left it sitting for a while (can't remember) as I would have thought engine heat would boil it off. Cap seemed tight as well. Now I start engine and warm it up after washing to try to get of excess water.

 

[roy]

Yeah, same problem with same plug when I wanted to fog cylinders for winter storeage last fall. I could only think I must have washed the bike and then left it sitting for a while (can't remember) as I would have thought engine heat would boil it off. Cap seemed tight as well. Now I start engine and warm it up after washing to try to get of excess water.

So your's was the same plug? that is odd, something must be wrong with that particular cap. I rode in a suprise down pour this morning on the ride into work so mine probably filled up again. I would think the heat would burn it off but evidently it runs cool on the head.