Head tube - white crud

I believe the tube you are talking about is the breather hose. That is if I am reading you right. Your talking about the top of the engine right?

It is normal for oil to leak out of that tube after a ride. Not much though. As for white crud leaking out of it, I have no idea. Unless you submerged your bike under water lately and your oil turned milky white because water got in there.

It's normal for a few drops of oil to drip out of the head breather/vent tube. The whitish color might be due to frothing. Mine comes out as regular amber colored oil. With your engine idling, put your hand near the end of the tube and you can feel the crankcase venting in pulses. The oil coming out a little is because of the oil mist in the pulses. It builds up slowly over time and a drop will come out here and there. The only thing to be alarmed about would be if you drained your oil after running the engine for several minutes and the oil is milky white. That would be a sign that coolant is getting into your oil...usually a blown head gasket. Not good!

If it's cold where you are it is very normal to see a white colored oily residue coming out of the vent hose. When you are running the engine , and letting it get cold ,you build up moisture in the cases, especially in the valve cover area. I wouldn't worry about it, unless you pull your dipstick and find it milky looking too.

Wr426,after the 1st ride i found some white crud/oil? leaking out of one of the tubes. I traced the tube back up the bike and it was leaking out of the large tube that mounts directly on top of the head. Is this normal? what do you think this crud was and what is that tube for?


WR426 Power!

Thanks for the help, much appreciated!


WR426 Power!

I noticed the same thing the other day, that milky white solution.

I haven't heard about the condensation build up in the case, but it makes sense.

I've always thought that it was due to riding in deep watery conditions. The breather tube you are talking about has positve and negative pressure constantly acting in it. Thus some water will get sucked up and pushed back out. This tube is coated throughout with overflow oil from the case and when the water and oil mix it makes this milky white fluid. What you are seeing is that mixture making its way out. The hose is designed to be long enough not to suck water into the case, but just to be sure check the oil at the filler if its normal you are ok, if its white you've sucked water, change it soon...


JJ - 99 WR; WR timed, stock jetting, Scotts stabalizer, Scotts triple clamps, Pro-Tapers, Terry Cable Hot start, MSR Raptor clutch lever, Moose skid plate, Works frame guards, Acerbis Pro Rally guards, Renthal MD-soft grips, Russel speed bleeders, Factory Effect graphics, YZ rear fender

This may sound silly, (because it is) but it could be some of that white plastic that Buck had in his cylinder head cover.

Now, was that worth two cents?

nothing to do with white plastic bits making oil frothy white!

if you wash yer bike wter will find a way up & when it gets pushed back down it's frothy & white.

we've had several boys over here in britian stall in water & the engine sucked water up wrecking the engine.


I had some of that milky white froth drip out of my vent tube today right after I loaded the bike into my truck. Just another eccentricity of this machine....kinda like a woman.


[This message has been edited by Boit (edited 01-03-2001).]

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