S.O.S.: i need your help, please.

No oil return is definitely a show stopper. Might trace oil tank lines to pump and back out as there is an error in some manuals on this. Swarf from past or ongoing parts chipping can plug internal passages in some models. Swarf that entered in hot swollen passages can get trapped on cooling contraction and can be difficult to impossible to dislodge by mre wire or air.

pierodn said:

Hi.
The oil line is right.
No oil return.
Pump or oil paggages plugged?
Thanks
Piero

Click to expand...

"Pump or oil passages plugged?" Yes. As Jim said in his earlier post, "It is likely a plugged passage on the inlet side of the scavenge pump or maybe a damaged scavenge pump." To determine which it is will require dis-assembly of the timing (right-hand) side to allow access to the oil pump. Looking back at your original post, I don't read where any work had been done to this bike prior to the leaking problem. Did this come on suddenly? If something was done to the bike that might have dislodged some old gasket and/or sealing material, this could have gotten lodged in the suction side.

I would start by removing the oil pump and checking it over carefully for any failed components. Unfortunately, I don't have any pictures I can post, but the pump is a pretty simple item. Keep in mind that it's the wider set of gears that make up the scavenge side of the pump, so these are the items of interest.

If the pump looks to be in good condition, then about the only other thing it could be is an obstruction in the suction side. Sadly, this could require removal of the cylinder to verify proper port cleanliness. You could try removing the sump plug while flushing a cleaning solution from the oil pump mounting boss in the hope that the swarf would be expelled out of the sump plug port, but I don't know how much faith one might have in doing this.

Good luck, and please keep us posted with your progress.
Nathan

Piero,

please do this....

remove the oil filter completely for now

hook up the oil flow lines

start motor and remove the oil tank cap and look in there and watch to see if oil is squirting out back into the tank

report back here

I still think you have the oil lines reversed based on what you are reporting.......

Dear All,
I cannot believe in my incredible mistake!!!
I had fitted the oil pump gasket on the contrary and so i had plugged the return oil hole!
I cannot believe it, i know very well this, i ever say to my friends to pay attention to the side of this gasket.
Off course the pump works well.
Now that i have a part the timing, i will mount another timing, those of 850 ES with a anti wet sumping: do you agree?
Thank you for helping me.
Best regards.
Piero

Great news.
So glad you did not have to open the crank cases.
That thin paper gasket was the problem!

Bob Z. said:

Great news.
So glad you did not have to open the crank cases.
That thin paper gasket was the problem!

Click to expand...

Hey Bob Z.
Is that oil pump from a Combat (i.e. without the sump strainer)?
Ta.

Not sure anymore where the oil pump was from but something went through it.

The photo shows the double thick scavenge gears that are supposed to keep the sump oil level low when engine is running.