can i do it?

this may be a stupid question but im curious...bike is an 03 yz250f. rather than splitting the cases just to clean out the bottom end, would i be able to pour gas/diesel in the cases and swish it out and then pour oil in there? and i mean do this process while the cases are together and everything is in there. top end is off thoguh! only botttom end. now there is no particular reason i want to do this,i just want to make the bottom end is "clean" without splitting the cases.

Don't use straight gas because of the rubber seals. I have heard of guys using diesel to flush it out because it is more oil based and easier on the seals.

You wouldn't accomplish much except a giant mess and maybe a hernia! If there was any heavy particle, it's still going to stay in there unless you wipe it out. Swishing diesel in there is just going to wash the leftover oil off of your bearings, shafts, gears, etc and dilute your new oil. If you're going to do it, do it right but wouldn't split the cases just to clean it. You're better off just keeping up on frequent oil changes

just go ahead and split em. its not hard to do at all on the yz's. as long as the tranny stays in... if not its a major pain. BTW your way behind mine is almost ready to ride and you havent had a update in weeks :smirk::smirk:

and while your in there i would replace the rod and crank bearings..... they go pretty quick

Oh yeah, how's life treatin' you? How's the job?

If there is nothing the matter, and you just want to give a good clean, then you can use diesel, kerosene or jet A (helicopter fuel)

If you're just doing this as a cleaning, then rotate the engine over a bunch of times via the crank, then completely drain, again turning over the crank to get it out of the oil pump and lines.

keeping up on your oil changes would be a more reasonable way to keep your bottom end clean, I dont do diesel flushes unless i water log the motor.

Use auto tranny fluid. Swish it around a little, spin the crank a lot.

If you find anything: Split the case and get the rest of it out.

If nothing comes up: After you rebuild it, start it, let it run a while then change your oil and you should be good.

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