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Help with kx250f

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OK....I need some help maybe someone here has had a similar problem recently rebuild top and bottom end on a 2007 KX 250 had some issues with the timing but finally got it running,something wasn't right so I went to check the timing again and a whole bunch of oil dumped out of the stator cover I thought it might have been short-term collection but it was still in there the next morning why is it not circulating back into the crankcase but collecting in the stator?

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Ugh......bought a new cam chain, and again, bike started up rand great till I shut it down, waited 30 minutes did it again, ran great shut t down...thought problem was solved, put bike all back together today, sarted it ...ran for like ten seconds and died....started it again and HUGE clacking from top end. stopped bike immediately. open top inspection cover ( the one you check TDC with ) and oil started pouring out...WTF is going on...someone please help!...my kid is losing his mind and I'm starting to feel like a failure as a dad!

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Remove the engine from the bike and pull it apart.  Split the cases.  Too much sealant was used on the rebuild which is squished out into drain ports preventing the oil from returning to the sump.  Basically what is happening is the oil is getting pumped up to the head.  It comes out under the cam journals.  It splashes around lubricating the cams, buckets, valves, and chain.  The oil then drains down the cam chain slot to the bottom, under the flywheel cover.  In the back of the bottom of the case on the left side behind the flywheel there are ports that allow the oil to flow back into the sump, to be drawn through the screens picked up by the oil pump and sent around again.   Your case drain ports are plugged.  Your bottom end is starving for oil because it has all been pumped out and is accumulated in the flywheel and cam chain slot.   Your bottom end "may" be cooked from a low oil / no oil condition.

Pull the engine, take it apart, split the cases, cleanup that excess sealant, clear and ream the drain ports, clean the screens, inspect for damage signs of low/no oil.

Hope that helps.

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Dude!....thanks SO much, I was at the point where I just talked to a shop about taking it in and spending $$$ to have it rebuilt by someone else. I will take a look this afternoon again and keep the thread posted. Thanks for the info!

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Just for closure, I tapped out and dropped the motor off at a local engine builders, giving up and paying someone who has WAY more experience doing this....apologized in adavance for whatever they may find, and asked that if it was something completely stupid to please not tell me.

hopefully bike will be up and running by weekend.

 

Thanks everyone!

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Sorry this took so long....problem found....didnt realize there was a pin in the oil pump....it fell out on disassembly  and i never even saw it it.... $4 fix....thanks to all....on a side note...after getting bike going and running stronger than before...i let my kid change the oil after break in was done....he put filter in backwards and now im tearing down again for yet another top end job....crossing my fingers i can save the jug with some light honing....

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