Thanks. None of them do this until they are worked hard and engines are hot.
I was thinking timing, but I hate to mess with them. They start good and idle good and actually run good.
The tractor will scare the he** out of me. It will go off like a 12 gauge, just about the time I get off the seat.

Last edited by Old GMC Gold; 10/18/2014 9:59 PM. Reason: sp
57 GMC LCF 370
55 John Deere 40-W
59 John Deere 430-W
2000 GMC 4x4
56 John Deere 420-W
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