[Dead Parrot]

Another cause of dieseling is an idle speed screw turned in too much to compensate for poor idle mix adjustment or not enough idle timing. Keeps the throttle plate too open.

Sometimes it is easier to lube a choke cable if you take it loose from the carb, get it as straight as possible, then work it back and forth. Might spray some carb cleaner on the choke parts on the carb, they might be gummed up.

Don't trust the timing mark to be accurate. The balancer ring might have shifted. A PO might have installed the timing tab in the wrong place.