317 john deere

My aunt gave me a 317 John Deere that would not start. i got it and It sat for about a month the put some gas in it and turned it over and fired up after a couple cranks it fired up. But did not run right it seemed to have bad spark plugs. I ran it and it started right up every day for the next month. Then I shut it off and it would not start back up again. I bought a new coil and it still will not start. And I have no spark could it be the new coil or what else should I check. It only has 80lbs of compression on both sides. Could my battery be shot or dose the motor need to be rebuilt?

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