Hole on the right side of the engine

[pba123]

On yz250f's there is that small hole on the right side of the head above the exhaust header. What is the hole for or what does it do? On my 04 there is always a little trail of oil coming out of it. The oil line reappears even after I change the oil and wash the bike. Can someone help me out? Thank you

[Turismo]

it is a drain hole for the hole where the spark plug goes into.

it is most likely water, not oil.

[joshb]

I have no idea but just a thought, maybe you're spark plug isn't tight and oil is coming out from there?

[OWENLO]

Your gasket that seals on the cam cover(the one with the 2 half circles) is out of whack and letting oil in the spark plug well from the top end.

OWENLO ?

[aedwards07]

THe hole is to let water escape or sometimes enter when you polwerwash the bike.

[pba123]

I am still not sure what it is....is it a water drainage hole or a problem from a leaking gasket, or is my spark plug too loose.....? ? It is dried on which is why I am starting to think that it is not oil, but I am still clueless

[nori41]

Not sure what purpose it serves, but in the manual, Yamaha recommend you block it up when power washing your bike.

[offthewall]

Well, it is definately a drain hole... we have established that. In my experience though, it will leak ONLY if the gasket is messed up. If water is draining out of it after washing, don't worry about it... but you said oil. Therefore, invest in a new gasket! It won't hurt (think, if this part is ruined, perhaps a whole new gasket kit would keep your baby running better and longer)!

[Slowmotion426]

If you'll read your manual, it'll tell you that hole is there so you can blow out any dirt/water that collects in the spark plug hole. You use an air gun to blow out any dirt/water in there before changing a sparkplug. ?

[nori41]

If you ride in really wet, muddy conditions it can look like it's oil seeping out of the hole but it could be just dirty gunk seeping out.

I can clean my bike sometimes and still find a dirty trickle emerging days later.

[pba123]

If you'll read your manual, it'll tell you that hole is there so you can blow out any dirt/water that collects in the spark plug hole. You use an air gun to blow out any dirt/water in there before changing a sparkplug.

I checked through my manual before I made this thread. Do you think that you can give me the general chapter or even the page number that this info is on, because I apparantly missed it ?