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Leaking Oil

2740 Views 4 Replies 3 Participants Last post by  yfzstar410
Hi everyone, newbie here.

just wanna start off saying i've always loved yami's and started really riding the mx quads just a couple years ago and purchased my 04' yfz (used obviously) almost a year ago. I was curious if anyone could tell me what is the point of this hole in the side of the cylinder? I am leaking a little oil out of it along with what looks like more oil out of my exhaust port and header.

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thats the drain hole for where the spark plug is.make sure your spark plug is tight
If you're sure it's oil you're leaking from thee, you might ant to replace your valve cover gasket aswell. I couldn't think of another reason while oil would be coming from there.
thanks for the help fellas. Also, what are some of the signs of a leaky valve? If oil were leaking passed one of the intake valves, would it change to a gas or smoke through the combustion process or stay a liquid and leak outta the exhaust?
i pulled my valve cover off and turns out i do need a new valve cover gasket. there is a tear on the gasket right by the spark plug which would explain oil comming out of that hole. as for what i am seeing comming out of the exhaust. i just installed a new gytr pipe and heard its just the gasket melting. but i pulled the plug and it looked like this after i wiped it off a little with a rag. are one of my valves leaking?

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