Fix the 188D. Relatively common engine with a very common injector pump. It is possible to remove and reinstall the injector pump yourself.
Those old Case engines run forever. I am around 2 of the 188Ds that are well past 5000 hours and showing no sign of slowing down, and also a 148G (gasoline burner) with over 14,500 hours.
It will cost you far more to repower than it will to pull the injector pump and get it rebuilt. Also the 188D is a very fuel efficient engine.
The 1835s being repowered are the 1835Cs that had the Continental/Teledyne engines. They were trouble in those loaders.
