Mark here is what my DF 140 manual says
Break in period 10 hours
Break in procedure
1. For the initial 2 hours:
Allow sufficient idling time ( about 5 minutes) for the engine to warm up after cold engine starting. After warming up , run the engine at idling speed or the lowest in gear speed for 15 minutes. During the remaining 1 hour and 45 minutes operate the in engine in gear at 1/2 throttle (3000 rpm)
2. For the next 1 hour: operate the in engine in gear at 4000 rpm, or at three quarters throttle, avoid running the engine at full throttle.
3. Remaining 7 hours: operate the engine in gear at desired engine speed. You may occasionally use full throttle, however do not operate the engine continuously at full throttle for more than 5 minutes at any time.
then in bold it says
note for the remaining 7 hours of break-in operation, you may use full throttle, however do not operate the engine continuously at full throttle for more than 5 minutes at a time or severe engine damage such as seizure may result
Best
Eric