D4D engine swap can I use Gen 3304 motor?

the injectors, governor and pistons could be different too. might be better to find a matching block or short motor to get what you need. depending on exactly what happened it may not be that difficult or expensive to repair the damaged engine. but that requires pulling it down and inspecting everything.

yes it might be cheaper but then your machine isnt as original. might put undue stress on other driveline parts due to higher output plus the unforeseen issues in making it fit.

One of the main differences between Industrial/stationary engines and tractors  is in the lubrication system. Industrial engines usually have a single section sump oil pump where tractors use a forward and rear scavenge system with a three section pump to accommodate inclined usage. If the oil pump is damaged it may not be transferable to the Industrial engine.

Good point on the oil pick up. Yeah finding used 3304 is in Southern California is like in the sea ‘ cause they want them all in the scrap yard. This is the first one I’ve seen in two years. But thanks guys for the input any other insight would be great.

I would open it up first and see what has failed. Maybe just need to change the crank and a connecting rod or two. Was it run with out oil or did it just slowly start knocking. if it is a con rod you should be able to see it as soon as you have removed oil pan. I have done swaps from different machines ( ag to construction / gen to construction ) and it has always been just as much or more work than if customer had just gotten a crank. Usually front and rear structures are different intake and exhaust manifolds fuel system flywheel and the list goes on.