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HELP 2007 kx250f oil leak

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I just purchased a 2007 KX250F and noticed that immediatly after starting it cold, a decent amount of oil leaks from the crankcase breather hose. I drained and refilled oil to proper level and no change. also continues to minorly seep some oil when riding it.

I have done much research and noticed this seems to be a common problem with no real remedy and may be caused by the clutch slinging oil around and pushing it out of the breather.

My question is... would it be a reasonable idea to move the crankscase breather from its current location (under the carb) to somewhere ontop of the valve cover. Im pretty sure I could remove the valve cover and find a safe spot to drill and tap a threaded bung for a hose in and I would think it could still breath properly..?

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I just purchased a 2007 KX250F and noticed that immediatly after starting it cold, a decent amount of oil leaks from the crankcase breather hose. I drained and refilled oil to proper level and no change. also continues to minorly seep some oil when riding it.

I have done much research and noticed this seems to be a common problem with no real remedy and may be caused by the clutch slinging oil around and pushing it out of the breather.

My question is... would it be a reasonable idea to move the crankscase breather from its current location (under the carb) to somewhere ontop of the valve cover. Im pretty sure I could remove the valve cover and find a safe spot to drill and tap a threaded bung for a hose in and I would think it could still breath properly..?

The breather hose is supposed to be over the intake, NOT UNDER the carb.

Here is a pic of my old 07 where I had routed the hose on the back side of the carb to give better access to the fuel screw. Stock it runs in front of the carb over the intake:

IMG_1373.jpg

I did the same thing on my 09, but in this pic it was as it came brand new:

IMG_1410.jpg

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Sorry i meant it comes out of the case under the carb and is routed over the carb intake like pictured in yours but it still seems to push alot of oil out and im not how to correct this problem

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You know I forgot to ask you.. when you drain your oil.. do you drain from both oil drain bolts?? if you do not drain the 8mm side and refill the bike.. you're around 50-100cc's over filled and that might also be the reason you're pissing oil all the time..

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yeah i did drain both sides and leaned the bike both ways to make sure the majority of the oil was out. I replaced the oil with the measured amount from the manual and let the bike sit. it spews everytime i start it, not necessarily after an oil change. Even if i dont see any oil in the window it will spews on startup. Its very frustrating and thats why im considering moving the breather to the valvecover gasket somewhere. Im thinking it should breath just as well as other bikes have their factory breathers located there.

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well, if it's doing it every time you have another problem and moving the breather hose is just a bandaid to the orriginal problem.. how much oil are you putting in? I know you said what the book called for but tell us how much you are putting in?

My bikes have dripped a little bit of oil here and there but not everytime the bike has started up.. and not a cap full immediatly..

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Why is there 2 threads on the same problem?

Also, tell us how much you have been putting in there.

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im putting in .79 quarts without changing the oil filter. Even after that, there is no oil showing in the window.

and yes i did post on 2 different sections because im not familiar with this forum.

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im putting in .79 quarts without changing the oil filter. Even after that, there is no oil showing in the window.

and yes i did post on 2 different sections because im not familiar with this forum.

That is too little oil for an 07 actually. Your bike has a total of 1.5 liter. When changing oil without filter it needs 1.3 liter, so you are 0.5 liter short. Not good.

09 and up takes less oil.

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10-40 is good for most type of riding.

You could switch to a lighter 5-40 if it is very cold outside.

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That is too little oil for an 07 actually. Your bike has a total of 1.5 liter. When changing oil without filter it needs 1.3 liter, so you are 0.5 liter short. Not good.

09 and up takes less oil.

WOOOO... NOOO 07 is 1.5ltr dry.. normal oil changes is 1.35 with an oil filter change and 1.3 if the oil filter is left in..

I run 15w40 shell rotella T

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WOOOO... NOOO 07 is 1.5ltr dry.. normal oil changes is 1.35 with an oil filter change and 1.3 if the oil filter is left in..

I run 15w40 shell rotella T

Lol isn´t that exactly what i said!?

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Im wondering if it was just the oil. The previous owner said he always ran

20w50 so thats what i replaced with. Im wondering if the fact that the oil was too heavy that it was just pushing it out. I am going to change again with 1.3 10w40 and see what happens. Thanks alot for all of your help!

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