05 yz250f

How's it going thumpers. Just joined the site and this is my first post. Any help on advance is greatly appreciated.

I have an 05 yz250f. Yes I read the faq on this particular bike (lol) before I made this post.

Here's the run down. I got the bike in a trade. Done an oil and filter change immediately on the bike with no issues. I took it to ride the next day and after about 4 hours it went down. My buddy seen oil leaking from the case, low and behold there was a hole busted in the case.

I tore everything down to find that the way pump gear had snapped in half and went through the case. Upon further inspection I found that the water pump turbine channel was full of sand.

That's my first question. What would actually make that possibly happen?

So continuing on. I replaced both the left, right cases and the clutch cover case, piston rings, transmission, gaskets, oil seals, crank bearings, and water pump.

First ever rebuild! Bike is back together and running very strong. My issue is with the oil. I can't seem to get enough oil in the bike to read at a safe level on the dip stick.

The motor was bone dry due to a drained frame and cases. I have cleaned out the in line filter running from the frame to the motor itself also. I can get a small amount of oil right at the dip of the dipstick to show. But after 1.5 quarts I'm still at the same level.

Why can't I seem to get it between the hash marks on the dip stick?

Should I keep adding and adding until it corporates?

Or should I put the recommended amount of oil per the manual and ride it?

Or do I have possibly another issue with the bike?

Sorry for all the questions, but the bike is wearing my hopes thin and I need a solution.

Thanks

Did you run the bike then check the oil ?

Because my 450 won't show oil before its started and running then I have to immediately check it or it will drop again

Yes. I added the specified amount. The bike doesn't like to idle right now. So I putt around the yard for a couple of minutes. Then let it sit for 4 to 5 minutes and checked oil level

I'm still trying to fully understand this carry the oil in the frame concept too

Check the oil immideatly after

Don't wait

I tore everything down to find that the way pump gear had snapped in half and went through the case. Upon further inspection I found that the water pump turbine channel was full of sand.

That's my first question. What would actually make that possibly happen?

 

I've seen this in two motors my whole life...

 

The first motor was a jetski motor, which doesn't have a radiator at all, but instead pulls the surrounding sea water into the engine to act as coolant and then dumps it out the back.  When I took it apart, the entire cooling system was packed with sand (you can imagine why)

 

The second time I saw this was when my brother accidentally launched his kx250f into a pond at the racetrack and we spent the rest of the day trying to fish it out... the bike obviously wasn't running after that, so we tore it down completely, inspected the entire engine, gearbox, cylinder, literally everything EXCEPT the inside of the radiators and coolant hoses.  We put fresh oil in it, fresh coolant, fresh fuel, started it up and it ran perfectly.  The next time we went out riding, after a couple hours he started leaking oil from the case (but his bike continued to run).  We took a look at it and discovered that the case was cracked.  After tearing it apart AGAIN we found the water pump had self destructed and there was sand and little pebbles all up in there.

 

I have no logical explanation for how that could have happened either, but whatever happened, it happened when he dumped it in the pond.  I wouldn't be surprised if your new bike took a swim somewhere sandy before you got it.

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