Valve clearance on a 155z engine

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Coop88

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Ive got the t on the magneto at the rope and the line on the cam sprocket is lined up but when I do a full turn the t is back at the top and there's a second mark on the cam sprocket that is lined up. So I can't tell which turn is tdc. Can sprocket has a dash then FL then another dash. Which is the right one? Cheers guys
 
As long as the flywheel T lines up to the notch at 12oclock and the cam sprocket lines up with the dash at 9 oclock then you are basically nearly there, all you need to do is pull your plug out and stick a screwdriver in the plug hole carefully and it will come to a stop if the piston is at Top Dead Centre. If the piston is not at TDC then turn the flywheel around again to the T and check the plug hole again. Leave the plug out because when you do get it at TDC the flywheel will usually fall back or forth of the T mark as its on the compression stroke.
 
dont scratch the bore or damage any threads with that screw driver !
 
Sweet thanks mick I'll give it another go. Annoying how they have 2 marks ay seems a bit stupid
 
Screw driver didn't help because the piston is at the top on the first mark then if I do a full turn to the secon mark the piston is at the top again. How am I supposed to know when it's tdc on the firing stroke? And what does FL stand for?
 
you want the power stroke, where the intake valve closes, and the exhaust valve starts to open.
the cam marking will line up with the mark at 9 o'clock on the head.
 

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