Oil coming out of vent tube?

[2000drz400e]

Guys I need some help. I have been working on a 2000 drz 400e that I just got. I runs great but when you run it hard (anything over half throttle for 30 second or so) it start to pump oil out of the vent tube coming out of the black box. I have checked all the lines going in to the black box and they are clear. The bike is all stock except of a manual timing chain adjuster from thumper talk. It seems to be filling the box full of oil and pumping it out the vent. I have no idea what's going on. Oil is filled to the full mark on the dip stick and the bike does not smoke and start right up, just pumps oil out when ran hard. Any help would be great!

[Craigo]

So is the oil coming out the hose from the breather box that is routed under the seat??

Are you measuring the oil level when the engine is cold or after it's been running??

[Qqqqqqqqqqqq]

How many miles on this motor ?

[2000drz400e]

Yes its the hose that routes under the seat and goes by the air box but does not go into the airbox. The hose connects to the top left of the little black box on the right side of the bike. The box has two other hoses, one going to the valve cover and the other going to the bottom of the cylinder. I pulled the box and the hoses and blew them all out and they where clear, also blew out the valve cover and cylinder port. I check the oil cold with the bike on the side stand. I have no idea how many miles the motor has on it. The manual timing chain adjuster is in pretty far, a couple two or three full turns from being bottomed out. But the bike runs great, it starts easy, doesn't smoke out the exhaust and the one time I rode it, it felt strong.

When it is idling I can fell air coming out of the same vent hose almost like an exhaust pipe (has the same rhythem as the exhaust), but no oil comes out. Then when you hold the revs up it fills the black box full of oil and it starts coming out of the vent tube. Its not draining back into the motor some how or the motor is building up to much internal pressures and holding the oil out.

Is there any other vents that might be stopped up?

[drrick]

its over flowing because you have to much oil in the bike.

drain the oil from the engine and the frame plug.

add 2 qts. of oil and you should be good.

to check oil level, check with bike hot.

start the bike, let it run for 3-5 mins.(i usually ride it a bit)

shut off engine let it sit for a few mins. stand bike up level

and check oil.

good luck

[Craigo]

I Agree...Oil is overfull..To get an accurate reading check the oil level mid ride or after returning from a ride....That way you know it should be good to go for the next....

When you drain the oil make sure you undo the 2 drain bolts...it would be interesting to measure how much actually was in it....

[Noble]

I agree, probably too much oil. If drain and refill with 2 qt does not fix it, then the motor is simply tired and has a lot of blow by. Needs new piston and rings.

[Qqqqqqqqqqqq]

New piston rings , cam chain and head work should do the job

[xxdabroxx]

Big bore while you're at it.

[Craigo]

Big bore while you're at it.

So why stop there..... ?

[Qqqqqqqqqqqq]

Yah ... Next stop ... Stroker town

[2000drz400e]

Thanks of the thoughts guys. As soon as I get back home to work on it, I will let you know what I find.

[2000drz400e]

Thanks for the help guys you where right to much oil in the bike. Drained the frame and motor and there was maybe 4qts in there, so I feel smart.

[Craigo]

Thanks for the help guys you where right to much oil in the bike. Drained the frame and motor and there was maybe 4qts in there, so I feel smart.

Don't feel too silly....the dry sump engine has made lots of new owners look retarded....

I made the same error way back in 1976 when I purchased my first dry sump Yamaha TT500...Didn't read up in the manual and overfilled it big time...

Live and learn I say...... ?

Edited September 16, 2012 by CraigoDRZ485sm