2002 YZ, white oil dripping...

Hey guys, I searched as much as I could and I couldn't find a definitive answer on this one.

I have a 2002 YZ 426 with 5 rides, 1 race, and after every ride the oil vent hose that hangs down by the shifter is covered with white gue at the end.

I know this generally means water/coolant is mixing with the oil, but the "shop" claims there is no water in the oil, and no head gasket or water pump leak.

The engine oil wasn't white when I changed it, but it did look a little thin and slightly beige, but not white in color. The coolant level seems stable.

Anyone else out there see this?


2001 Natl Hare & Hound Champ, 4-stk Am

There have been a few threads on this and they all point to condensation. Just keep an eye on coolant level and your oil changes.


I had noticed the same problem with mine and the shop could find nothing wrong. I have a skid plate that the drain hose flows onto and I notice quite a bit of blow back from it. I have not not seen the milky color since last winter but I have not ridden in the cold either.

Condensation sounds reasonable, it's a long hose, cold when you start it, warm gases get into the hose and condensates then a little blow back and viola...

Who knows...

I do wonder how much seepage or blow back you guys normally get? Some days it seams minimal other days it seams excesive on my bike. Could lugging around in too low a gear cause this as it seams heavier when I ride third to slowly in corners...

You know, that might be it: cold weather. I've never really ridden in cold weather before and it's been a lot colder than usual these days down in California. When I say colder I mean 30-45 F... It's funny saying that because I'm up in Canada right now and have been snowmobiling in -10 F..., so 30 F is not that cold for me...

When I get back to California I'll ride on a warm day and let you guys know.

Joy Noel (Merry Christmas),


If you tried to start the bike in a waterhole, up to the drain hose, water will be sucked into the motor. You will know this immediately when you change oil. It will be very milky. If this has not happened, you have probably overfilled the oil capacity & frothing is taking place that is draining out - I have seen this on mine at times also. Also keep a eye on coolant level to see if it drops drastically - hopefully this is not the culprit.

I have an 01 426 that sits ouside in a detached garage that is exhibiting the exact same symptom and it has become more prevalent since it has cooled down in temp. However, the oil is clean after every change so I'm pretty sure it is just condensation in the overflow tube.

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