Re: Gravely 812 Dies with PTO Engaged or Any Load
My first guess would be that the engine is not getting enough fuel under load. You might want to try readjusting the "high" needle outward (richer) a quarter turn, or so for starters. You might also want to double check the points to be sure that they are gapped at 0.20 in. Over the years, I have noticed that they tend to close slightly when tightened, and have had to readjust them.
Also, if you haven't already done it, you may want to take your carb. apart and clean it, including spraying all of the passages with carb cleaner using the straw. There are also tiny holes, barely visible, in the long needle that clog up. Try alternately spraying into them with the carb cleaner straw pushed against each of them. You should see carb cleaner spraying out of the others.
Finally, is it possible that the shop adjusted the governor? If so, it may have been done incorrectly, and may need to be readjusted.