I've got a 1600 xflow engine which pumps smoke out of the rocker box filler. I've tried everything (mostly as a result of suggestions from this forum). I decided that a rebore was the only course of action. When I took the rocker cover off I noticed that the valve stem seals were half way up the valve stems. Could this be the cause of the smoking - oil finding its way down the valve guide?

heavy breathing is caused by bore / ring wear,the valve guide seals stop oil being sucked into the engine on the over-run i am afraid.

+1: Rebore and new pistons I am afraid, so go for some 1300 pistons to raise the compression a bit and free-up some ponies...

Thanks for the info. I had an idea I'd end up with a rebore etc!!

the old hat-type stem seals will move up and down togehter with the valves...so nothing to be worried about.
they seal when the valve is open.


dont worry about a rebore.....most tuned x/flows smoke out of the crankcase breather / rocker cover