2009 KX250F leaking oil out of weep hole

My 2009 KX250F is leaking oil out of the weep hole. Every time you crank the throttle back it bogs for a second and then revs up. I took the spark plug out it is soaked in oil. I've read something about the waterpump o-rings? Any ideas?

valve cover oring gasket and there is one under the cam mount.

Those are the ones you need. Most likely the one under the cam caps is causing the leak because it is ripped or not seated correctly.

Awesome. Thanks for the info. Do you know if you have to pull the cam(s) out? Or just the cover?

quick question, have you done any work on the head recently or did this just start on its own?

quick question, have you done any work on the head recently or did this just start on its own?

No, I haven't done any head work recently. I just got the bike a couple of months ago, so I'm still new to it. It just started doing it on it's own.

there was an issue with the 09 and the breather system.. What it did was preasurize the motor till the something blew.. I remember it was the head cover gasket but i wouldn't see why those orings by the sparkplug blowing either..

Awesome. Thanks for the info. Do you know if you have to pull the cam(s) out? Or just the cover?

Cams can stay in with the chain on them, but make sure you take out the chain tensioner before you loosen the cam caps and take them off. I made the mistake of not taking out the tensioner and the cams jumped out of their seats and I had to redo the timing :thumbsup:. Dumbest mistake I've made in awhile.

^^^^^^^^^^^ Yeah that sucks!

So we were able to get the valve cover off and the cam chain tensioner off, but noticed that the bolts holding the cam cap were not bolted down very good. We went ahead and replaced the o-rings and tightened everything down. It seemed to throw the timing off because then the bike wouldn't start. We ripped everything down again and got it timed and the bike starts, but now we hear a loud "knocking" sound. Is the timing still off or do you all think something else is wrong? We set the timing according to the manual.

if the bike was leakin auctual coolant, then the o ring under the cam saps and valve cover woudl not solve the problem cause there is not coolant in there, only oil.... thus if it was leakin oil, that is how you would go about fixing it. if u have coolant comming out of the weep hold o nthe cylinder head, u have a cacked head :excuseme: trust me i recently found out.

if the bike was leakin auctual coolant, then the o ring under the cam saps and valve cover woudl not solve the problem cause there is not coolant in there, only oil.... thus if it was leakin oil, that is how you would go about fixing it. if u have coolant comming out of the weep hold o nthe cylinder head, u have a cacked head :excuseme: trust me i recently found out.

Thanks for the reply. The bike is not actually leaking coolant out of the weep hole, just oil. Any ideas why it would be knocking?

ok oil is way better than coolant, replace the o rings under the valve cover and the cam caps. check the valve clearance as far as the knock goes. if the valves are in spec then id say ur fine. these 4 strokes have alot of weird sounds to them and are usually fine cause of their fast revolutions, (2000 rpm idle). how many hours are on the bike? i wouldnt think it would be the crank at all if its under 180 hours, my 09 has 181.1 hours on the stock cran kand its still fine but im in the process of replacing it.

Thanks for the reply. The bike is not actually leaking coolant out of the weep hole, just oil. Any ideas why it would be knocking?

Re-check the valve timing. Take your time and be very exacting.

Re-check the valve timing. Take your time and be very exacting.

Care to explain how valve timing will allow oil to seep out of the wheep hole?

The OP tried to fix a problem (I have assume it is resolved) and in doing so removes the tensioner and cams then has a new issue (now having a knocking noise) and then asks why this new problem is there. This is a much more important issue than the origianl minor oil leak out of a spark plug weep hole.

The OP also makes no mention of having throughly cleaned out the plug cavity (with the valve on, spark plug installed) so he will probably get residual oil for some time.

The OP tried to fix a problem (I have assume it is resolved) and in doing so removes the tensioner and cams then has a new issue (now having a knocking noise) and then asks why this new problem is there. This is a much more important issue than the origianl minor oil leak out of a spark plug weep hole.

The OP also makes no mention of having throughly cleaned out the plug cavity (with the valve on, spark plug installed) so he will probably get residual oil for some time.

Thanks for the help. I haven't had a chance to get out there and redo the timing. I think we have the timing just a bit off. We'll check the valves too.

Any time you have the cams or tensioner out, after you have it back together, with the spark plug out, slowly turn the engine over with a wrench on the flywheel.

It should rotate nice and smooth, only time you should feel any resistance is as the cam begines to push the valve down. To get an idea of how it should feel, do this next time BEFORE your remove the cams/tensioner. Then on reassembly, it should feel the same.

Finally, after you have together, always check the markes, Rotate the enginer two times and recheck.

Bent valves suck.

Any time you have the cams or tensioner out, after you have it back together, with the spark plug out, slowly turn the engine over with a wrench on the flywheel.

It should rotate nice and smooth, only time you should feel any resistance is as the cam begines to push the valve down. To get an idea of how it should feel, do this next time BEFORE your remove the cams/tensioner. Then on reassembly, it should feel the same.

Finally, after you have together, always check the markes, Rotate the enginer two times and recheck.

Bent valves suck.

Ok thanks for the help. I've always ran 2 strokes and this is my first 4 stroke bike, so the timing and stuff is all new to me. When we are timing it, I assume you put the piston at top dead center and then get the cam marks where you need them. Is this correct?

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