Z1a help needed please

[johnboy]

Hi
I have a Z1A imported from the USA in 1997, its never been on the road in the UK until now.
I have refurbished he bike and put it on the road this year.
It has been ok, but now no4 cylinder is smoking badly on start up. The plug fouls up and wont fire at all. When warm, with clean plug the bike seems ok, but next time on start up it smokes and oil is evident in the exhaust pipe. I have taken head and barrels off and cant really see a problem. Bores and rings ok, valves in guides not sloppy.

Please help advise if im missing something or what the problem could be
Thanks
John

[Steve Cooke]

My first thought would be the valve guide oil seals on that cylinder, are you sure the valves on that cylinder are seating properly?
It might also be worth swapping 1 and 4 leads in case of any weak current issues to that plug.

[breakdown]

Hi Johnboy. If theirs oil in there, it's either coming up past the rings or down from the valves, whats the compression like !! ( does a drop of oil in the cylinder improve the compression, get a comp tester).
As steven said valves cyl 4, by what you describe it's the exhaust valve that's the problem. would be my bet, check the in port on 4, any oil in there!!, Even though these parts might look ok doesn't mean they are.

If it's oil and fuel that's causing the prob....pub.

[PAULJAC47]

Hi, Make yourself a leakdown tester, I used an old spark plug to which I drilled out and fitted an old tyre valve held in place with liquid metal or araldite.Attach to a compressor with a pressure gauge in series,you can then tell if valves etc are leaking or not sealing correctly or if pressure getting past rings,Try Googling leakdown tester and you will get write ups on how to make one might save you a lot of bother Good luck Paul J...