Depends on how long you are going to keep running this machine and overall physical condition. Salvage yards are getting $3000-3500 for a running engine. It would be nice to know how many hours are on replacement engine. Reguardlees,I would put rod bolts in engine and at that time you could get a sense of what the rest of the internal parts look like (ie;rod bearing,main bearings,lower part of cylinder sleeve.). Another thing to consider is how much crop do you have left to take out. You don't want to make a hasty decision that you will regret later. Sometimes it is cheaper in the long run to rent a machine to finish harvest in a timely manner versus pushing to get a machine back running and then fight other problems. My opinion only, Hyper Harvest II