Z1OwnersClub GB

Is it possible for a valve guide to leek even after fitting a new seal?
I appreciate a worn guid may wear out seal quickly,but would have thought it would not leek straight away

yes. it can also leak if the valve is a loose fit in the head + will get worse when the engine gets hot

did you just replace the seal or put a new valve guide in as well ?

was the valve a snug fit in the guide or did it wobble ?

I didn't replace the guid.the valve was a bit sloppy.but didnt seem more than the others
i have used a endoscope to see inside the engine.There seems to be oil in the inlet port.but not sure if its running down the valve,or there may be a crack in the head somewhere

Couple of years ago i split a valve guide lengthways from over-revving when i missed a gear.
It bent the valve and when replacing the valve i found the vertical crack in the guide.
It was immediately after the event so no way to say if oil would have got into the port but i guess it would have been possible.

AL

Did you use genuine seals? some of the copies are very poor and leak after a very short time! been there got T shirt!a also there should be very little lateral
movement between the valve stem and guide..Is it blowing smoke on the overun? if so suspect seals/guides or combo!

Zman, it's probably a valve seal that was incorrectly inserted and it has not effected a seal. Circlip slipped off or not quite down.
The trouble is you have to pull the head off to remove the spring keepers to check. There is a way of pressurising the cylinder and remove the keeper and spring, however, that is hardly worthwhile if there is a possibility of a cracked valve guide or crack in head.

May as well do it now before the head is re-torqued.

RegardZ