Oil seperator 1978 KZ650 - leaking badly

Hi:
I rescued a 1978 KZ650. It was sitting for 5 years. On top of the crankcase is a round cover disk with a centre bolt and a vent for a tube. I am pretty sure there should be a tube from this vent to the airbox. The bike came without an airbox or this tube. I removed the 4 K&N air filters and fitted a used airbox.
My dealer says that the round disk covers the "oil seperator". When I ride, I am losing oil out of the vent, which is going all over the carbs and the airbox.
I removed the round cover disk and it just seems to cover an empty chamber about the size of a hockey puck. Is there supposed to be anything in the empty chamber like a screen or a filter?
I am reluctant just to add the tube to the airbox as it is likely just going to fill the airbox with oil.

The dealer suggested adding an external breather, but I do not think there is enough room to do this.
Thanks
jdornski

There isn't anything underneath the cover but what you see. That is a breather for the engine. Is the oil too full, that would cause oil to be pumped out the hole. What you can do is add a lenghth of hose on it and cable tie it to the frame rail so just the fumes make it out the end of the hose and blow out. You may be getting too much blow by also, if you hold your finger over the hole in the cover for a few seconds with the bike running and take it off you will get a little pressure release but there shouldn't be a "LOT".

Ride safe.

Post edited by: The Milkman, at: 2007/08/21 23:11

Hi:
Oil is too full I think. The sidestand is bent and the bike sits at too much of an angle and the I over filled as a result. It is pretty difficult to see through an oil level window that is 30 years old. I will try the tube trick.

I assume there is supposed to be a tube from the oil seperator to the air box?

Thanks for the quick reply.
John

with the stock air box the tube went to the bottom of it, a short hose and a filter on it to keep dirt out will work just fine

pretty sure you check the oil with the bike vertical. if you fill the window up with the bike on the side stand you are going to be way overfull.

Definitely put the bike on the centerstand when you check, change, or top off the oil. If the centerstand is missing have someone hold the bike upright. Also, I have found that after I change my oil I must check the oil level a couple times after letting the bike idle because the oil level changes (I suppose as oil is circulated through the system). Be careful not to fill to the top of the sight glass or you may end up with too much. Fill about halfway up the glass then run the engine at idle to warm it up a bit, shut off, and let sit for 10 or 20 minutes; then re-check. Ed

By the way, here's a picture of the little hose:

If not already done, would change the oil and filter.

Would also check the old oil for any gasoline odor which could indicate fuel intrusion into the crankcase via obstructed carb overflows (might explain oil level being too high).

And of course keep a close eye on the oil level.