2012 Kx250f rusty plugs

Hey guys , I currently own a 2012 KX250f and am doing my annual after ride maintenance. While unscrewing the sparkplug and such I found it to be quite rusty on the middle bit ( im not too versed mechanical grammar) and in the area surrounding the plug, like right at the bottom in its seat. Question 1. How do I go about cleaning the seat in the engine for the plug?

2. What NGK plugs do you recommend for a racing 2012 KX250F

3. How bad have I f%$&ed up?


Cheers, Conor :D

You haven't messed up at all. Someone will get you the stock plug. I don't have it in front of me. Try to keep dirt from getting into the cylinder. Shop vac before pulling the plug works. Unless its really bad in there now leave it alone. Or you could grease the threads of your old plug screw it down a few turns enough to seal the hole and hit it with WD40 and shop vac the gunk out.

Stay away from the plug with the power washer from now on. Lol.

Yeah I try to keep away from the general sparkplug area, but due to the little air vent hole in the side of the engine that leads to the plug cant really avoid it.

True that. Actually, that's another thing to do. Plug the hole like I said and make sure your weep hole is draining. Any oil coming out of it yet? That's pretty common. If it happens remember to replace the orings with 2013 parts. Good luck bud. Ride safe.

Bring the plug to any shop or read the number of the side and get a new plug... you likely got a little water down there and over time it got rusty


How many hours on the bike? how many times have you changed the plug?



online owners/service manual: FREE! read it!



Main & adjust page 39 down you will see everything on spark plug, page 25 says to check the plug after each race... says to replace every 7.5 in the manual... 10 hours isn't saying to much, they are cheap and if it has rust on it you waited to long.

Edited by nickbaldwin86

Stock plug. Dont get an aftermarket cheap brand plug they run like crap. I tried the auto parts store plug in a pinch before and its junk even though it was a direct replacement. You probably just got some moisture in the intake tract (air filter area) and it rusted up on the plug. This is why I start the bike after washing every time and always use a air filter box cover when washing. The hole on the side of the head is there for a reason, water easily gets past the coil stick and would just build up around the plug and drain into the cylinder when you remove the plug. The hole is there to allow that water/moisture to run out.

I think he is talking about the base of the plug inside the head.

those boots leak a bit and take on water when you use water blasters. I usually put a little rtv around the spark plug wire boot that meets the valve cover. It stops most of that.

Water in there will cause a sputter in your engine if the spark is shorting to case.

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