950 not sounding good, oil lamp flickering

Last time I started the engine (after 3 days of parking) it did not sound good, seemed to run on one cylinder only, after a while it seemed to be ok. Today (after 3 days again- walking city-tourist : ) ) the sound seems to be worse, it sounds as if the valves did not get any oil. In addition the oil lamp is flickering, even in gear.
I cannot see any obvious failure, oil level is good, screws to the exhaust were pretty tight.
Later I started the engine again to show a mechanic. This time the oil lamp first did not work at all, then just in neutral, then it went off again.
The last oil change is 2000 km ago. I did not have a new oil filter though (means the filter is 8000km old). There were no signs of malfunction until some days ago, The valves have been adjusted 8000 km ago.
Any ideas?
Thanks a lot!

Leaking water pump seal and or failed oil filter.

compression check is easy to do and can give a quick idea of what internal conditions might be.
Pull oil filter, screen and magnetic plug and look for debris.

Sounds like water pump seal failure and water in the oil.

Take off the clutch cover and see if there is milky oil. If there is you need to change the seal and change oil and filters.

See here how to do it http://www.ktm950.info/how/Orange Garage/Cooling System/waterpump/Rebuild/ktm_water_pump.html

Thanks for the quick and helpful answers. It makes perfect sense and even explains why I have to refill coolant without seeing a leak, And in 3 days the water had much more time to intrude than with every-day-riding. Maybe that is also a reason why the clutch slips when the engine is cold and why the oil level differs (had to add quite a bit. Plus that I noticed some weeks ago that there was pressure in the oil tank (when unsrewing the dipstick...pffff!). Allright, good to know who the enemy is...so long, time to eat and have a beer.
Ciao : )

If you have a paper element oil filter odds are it will be wavy from absorbing water. That causes it to stop passing oil through. Pleats should be straight.

Today we stripped the girl and opened the engine. The machanic (KTM, but no experience with a bike like this) says the timing chain is that lose that the tensioner cannot tighten it enough (front cylinder) and that there was no leakage from the water pump (oil looked normal, but I could not communicate with him why he was so sure about excluding this probable failure just by opening the pump to the rotor).When turning over the engine there is a clic-sound at one point (seems to come from the valves (front cylinder). i hope tomorrow will bring more clarity and an inexpensive and fast solution...(they have already talked about three weeks for parts..., guess there must be a faster way from the States)

I would be very cautious at this point - everything else you have posted points to a leaking water pump seal. The tensioner is hydraulic (this why it clatters on start up and when the oil light flickers). You have said that the coolant is disappearing, where is it going? Also what has a loose cam chain got to do with low oil pressure.

Have a look at the oil filter and maybe post a pic-up. It is pretty apparent if there is water in the oil.

Take a good look on our thread and see what you are looking for, specifically the oil filter photo showing wrinkles

http://advrider.com/forums/showpost.php?p=20374923&postcount=719

Don't worry about the "click" noise as you turn the motor over- that's normal. As far as the noise at start up, it could be a loose cam chain tensioner but it could also be coolant in the oil. Like someone else said, the coolant has to be going somewhere! First thing I would do is pull the filter and check the condition of it and the oil. My 950 will flicker here and there and I'll get some clatter from the cam chain, especially when the oil is about due to be changed. Low RPM's at idle can also be a culprit. RPM's should be around 1400 as I recall.

Check the easy , obvious first,, OIL, FILTER, CLUTCH cover, etc.. Also the seal rings on the coolant pipe that goes into the pump are suspect for leaking and not showing any obvious clues ( loss of coolant). As for the cam chain, I would not touch anything there until you can truly access the oil / coolant. No point in diving into extra cost . Yet.

Thanks once more to all of you! I really appreciate your help!
So, today I pulled the clutch cover and confirmed what we all think. There is white greasy stuff. The oil screen looks good. The oil does look more or less normal (I would say).
The guys in the "KTM"(?)-shop know less than me (in that case) and look at me as if I was an alien when I show and explain what i think. I even showed them your posts, in spanish. They do not reaaly seem to be interested. Not sure if I hurt their pride by showing them that most of what we did yesterday was not neccessary (I told them from the start that we should check the coolant issue and they said it was fine)
I said: order all the parts we most probably need. But no, he first wants to be sure what exactly we need and says in the same time that it might take 3 weeks (from Austria). Do you think he would make an effort to find out WHAT EXACTLY we need?! It is ME who is wrenching...not sure if I want to lay my trust in their hands but now I have 10000 parts everywhere and hope that the guy knows where they all belong...

And that..............is why, I hesitate to buy another.

forgot one detail: the oil filter looks as expected, wavy.

It is your waterpump seal that failed btw.
No doubt.

All you need to order is a water pump seal kit (comes with a new shaft and 2 x seals), an oil filter and oil.

Replace these and tell the shop to leave everything else alone.

The only other thing you might need to replace is very possibly the spring for the bypass valve. But unlikely, do the filter and water pump seals first and then see.

I would tell the mechanics to leave everything else alone. If they don't listen take it off them.

Many people here have had the same symtoms, with the same fix.

Cool, hopefully that photo was of help then.

Good advice from ciedema, having just gone through all this it is that simple-ish

had to use a flame to get the seal out. What about the bearings. Looks like they have some signs of wear towards the space in between... What about the seals of the cylinder-head that they have already taken off? look good...the part number of the waterpump-cover-gasket seems to be wrong. In the data-base it shows a slight difference.

Yes, thanks! Sorry to read about your problems. Seems like we have more in common than we wished for...: ) But my screen and oil look good actually.
Good luck!

Yep, replace those bearings and shaft. Youll need to be careful not to nick the new seal going back onto the new shaft.