Z1OwnersClub GB

Anybody got any (helpful stevew) suggestions on a small problem on my gpz1100 turbo. Shutting the throttle after running boost it creates a vacuum between the turbo and carb (not the plenum chamber) and draws the oil out of the turbo seal make a cloud of smoke out the exhaust. I was thinking of some sort of electronic one way valve to relieve the vacuum, but any ideas would be appreciated. (over to you "hop a long" )

Steve, drop a mail to Dave Dunlop (fastbyme.co.uk). He'll know the fix if there is one. Tell him I told you to have a chat. He's one of the good guys.

All the areas between the carb butterfly/slide and exhaust valves (including the plenum) are subject to negative pressure when the throttle is closed.
If oil is being drawn from the behind the turbo impeller I would start by replacing the seal and also look for wear of the shaft and bearing/bush.

What he says
Seal will have to be changed and Dave will be able to do that for you while you wait.
I take it you have at least a dash-12 oil return hose from the turbo? The bigger the better really.
I run a pretty big oil return hose as can be seen in the pic below. I also have 2 big crankcase breathers, one goes to atmosphere via a Land Rover V8 flame trap, the other goes to an ally catch tank.

Will