Oil breather taking in water...seized. 2010 yz450f

I was out riding today and half way thru are ride 6 miles in the bush I notice my breather spitting out milky oil. With no way in with a quad or truck was forced to ride out. Almost made it back to the truck and the motor seized. My question is what kind of damage did I do to this motor? Also how can I fix the problem so it don't happen again?

Sucks only second ride on the bike.

If your riding includes water then you should reroute the vent to the air box or somewhere else high up where it won't drip on the exhaust.

As for the damage, nobody can tell exactly what damage you have done without opening the engine up. You did put water into the engine, so you can figure all your bearings probably have at least slight rusting. You might be able to get away with running them for years without seeing a failure, but maybe not. If your investigation requires splitting the cases, you should consider replacing all the bearings.

Since it is seized, you likely need a new piston and possibly a new cylinder or a cylinder repair.

Good luck.

how did water get in it?did you ride through a lake?are u sure the breather sucked in water and u didnt have a coolant leak?

how did water get in it?did you ride through a lake?are u sure the breather sucked in water and u didnt have a coolant leak?

The white milky oil coming out sounds more like a coolant leak. I thought they usually die when they suck water up the breather.

I thought they usually die when they suck water up the breather.
Usually the other way around; they suck water when they die while submerged. While they're running, the pressure in the breather reverses too rapidly to draw water up the full length of the hose, but the last couple of revolutions as the engine quits, or if you try to start it, can do that.

Dipping the ends of the carb vents can cause a stall, though.

Usually the other way around; they suck water when they die while submerged. While they're running, the pressure in the breather reverses too rapidly to draw water up the full length of the hose, but the last couple of revolutions as the engine quits, or if you try to start it, can do that.

Oh ok that would make more since. I've seen some long threads on this in the past but is it really that common of a problem? I've known quite a few people with yz's and wr's and have never heard of this happening and we've done a lot of riding in wet and flooded conditions. I still haven't rerouted the hose on my 07' but I'm not convinced it is necesary, my 98 never had any issues with that either.

It's never been a problem for me either. I see very little water where I ride (normally), but lot's of sand, and people report slurping that up, too. If you make a habit of not shutting the bike down or trying to restart it while the end of the hose is stuck in something foul, would should be OK.

I do not live in the desert and my rides do require me to cross some creeks and muskeg sometimes. It's that or do loser laps at the track! Not really my idea of a fun sunday afternoon. We do not have the nice riding areas like some states we need to go looking for good areas.

I did stall in water and my buddy has the same bike and had the same problem. Luckly I think the bike is ok. I have flushed the oil 8 times now and it seems to be running fine. I have figured out how to fix the problem. If you tee off the beather line and run into the air box it will solve the problem. This will allow the Breather to breath when under water and still allow oil to drain out when not submerged.

Thanks to all with "usefull comments"

Great site.

I have figured out how to fix the problem. If you tee off the beather line and run into the air box it will solve the problem. This will allow the Breather to breath when under water and still allow oil to drain out when not submerged.

Thanks to all with "usefull comments"

Great site.

Hey good to hear you got her running again. Just curious why you can't simply reroute the existing stock hose into the top of the airbox under the seat without putting a T vent system on? If you have the bike sunk that bad I think you will have more problems then just sucking up the vent tube.

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