I have to agree with Steve, the first thing to check is voltage at the batteries. If for some reason the engine would crank and start, but bats weren’t subsequently at full power and the alternator not working when you came out of storage, low chassis voltage can cause the symptoms you describe. Indeed, devices of all kinds, 120v, 12v, 3v, can behave with on/off cycling, etc., when diminished voltage pushes incomplete current. Remember that many an alternator has gone belly up trying to replenish banks that weren’t first charged via post or genset.
Joel