Problem after needle circlip change

I did not experience any rough running issues with my 912 UL after completing the SB but I did find the same circular scarring you mentioned. It was contained in the three faint grooves that are scored into the jet needle below the circIip. I polished it away with 2000 grit sandpaper. Engine ran fine so not sure why yours is misbehaving 

I have been thinking this through and my latest theory is that a flake of the Torque Seal on the connection to the fuel pressure regulator may have fallen into the fuel tube when dissembling it. I will be sure from now on to remove all Torque Seal type material before removing any connection of this nature.

Still open to any other comments.

Thanks!

Hi Keith,

Just a thought..

I found the left carb circlip in the #2 position. Later when i completed the right carb I found the circlip in the #3 position. That surprised me and I wondered if I had messed up on the left carb. I found one post here that said the engine may have come that way so I didn’t make any changes and all was welll. Just wondering how yours was set up?

Mine was set up in number 2 and 3 also. Surprised me at first, but replaced them in the 2 and 3 positions respectively. I then did some research and saw your post. It makes sense because of less resistance to air flow at the turbo entrance.