Okay, where is my oil going?

For as long as I can remember with my 750J, I've always had to add oil every now and again. Run it for a while, red light starts blinking and the computer says "OIL".

I had a problem a long time ago with oil leaking from around the shifter cover, but took care of that with a fresh gasket. It's kinda hard to pinpoint where else on the engine it might be; but after the last time I got the warning (I want to say it was a few weeks ago), I put the better part of a quart in to fill up the sight glass. Couple of days ago, I got the warning again. I also noticed that when I left work, something was spewing out the drainage hole on the left muffler. Couldn't tell if it was oil or water.

The last time, I ran a compression check, and got 115-120 dry across the board. I don't appear to be burning the stuff; either it's coming out of another engine seal somewhere, or another thought that crossed my mind is that bad valve seals are letting the oil seep down onto the pistons and into the exhaust pipes. Either that, or it's running so lean that it's burning the oil for fuel, like Rick has mentioned in the past.

I've consulted with Chacal and Robert, and now I'd like to ask everybody; how can one check for bad valve seals? A search of the forums says look for oil residue on the valve stems through the plug holes or exhaust ports. Yes/No/Future Cloudy Try Again Later?

 

I have the same bike with the same problem. Scratched my head bald because I did not know where the oil was going. Till I started tearing her down for a complete frame up restoration. When I went to take the boot off the swing arm to get to the universal joint bolts, the boot was full of oil. When I finally had the engine out, the frame in that area had a thick oily mud all over it from the oil and road dirt mixing. When I took the swing arm off the bottom of it was covered with the same. So when I soda blast the case, a new final drive seal will be ordered from Len. I hope this helps.

 

More than likely what razz has suggested. If you are losing that much oil in the combustion chamber your bike would easily be mistaken for a worn RD....

 

That was one of Chacal's suggestions after I emailed him late last night. I got a reply an hour later. He's either a robot or a Bering Sea fisherman, because I swear the guy never sleeps.

In any event, that one didn't pan out, I'm afraid -- the boot for the u-joint is bone dry.

I did spend some time with some of those paper shop towels, some engine cleaner and a bit of steel wool cleaning up all the gunk I could see. Saw a bunch of oil on the RH side around the brake lever, but no obvious leaks, although I did pull the RH crankcase cover just on the off chance. Thankfully, it too was dry.

Next, I started pulling the header pipes to get a better look at the valve stems. Those weren't oily either, and better yet -- what I thought was a mound of carbon at the edge of the exhaust port was nothing of the sort. There appears to be a thin layer of carbon, but nothing excessive. Ditto for the insides of the header pipes.

So, I'm no closer to solving the mystery, but I've got a better idea of what the problem isn't. As an added bonus, the final drive housing probably hasn't been this clean since it left the factory.

 

Have someone FOLLOW you in a car.
Push the Bike through the gears and do all sorts of Engine Braking and Accelerating and Shifting.

IF, you are BURNING Oil, ... the person in the Car is going to SEE it!

They will either see a Light Fog following you.
Puffs of Smoke when shift.
Worse case is you are going down the road looking like a Mosquito Truck.

If you are BURNING Oil because of a Leak; the chase car will see it.

IF, ... you are Burning Oil as Fuel ... The Bike gets HOT.
There's NO way for the Engine to dump all the Heat its making and you FEEL it and, ... If its bad ... SMELL it.

Look in your Aitbox and see if the Inner Box under the Boots is Oily.

 

I was just browsing through the forums, when there was a discussion about the middle drain plug. Perhaps that is a bit loose and is leaking a bit of oil?