HI Group
Sorry off topic here. My lawn tractor was having trouble starting and I found the valve clearances where simply way out in fact the arm was plain loose.
I have the clearances .004 inlet and .006 outlet.
I have adjusted it and the engine now started up fine but I'm not sure I have done it correctly The nut on the top of the rocker seems to have no locking mechanism so what is to stop it coming loose again? Although there does appear to be a small star socket in the adjusting nut. Is this the way of locking it. Is this a screw within the nut?