it is spring loaded and does not require looseing the differential . minor cutting of the metal shield is involved . it is worth the expense to replace it as a one piece.
there is a product called blue devil available at the parts house. it cost about $40. add it to the radiator and it should fix your problem. I have seen it work when someone can,t afford to repair a head gasket or cracked head. not exactly a proper fix but it might work.
dennis- what judy suggested is correct . There shouldn't be any damage to the old pump by letting it run dry for a while. make sure you get a low pressure electric pump and your test should work. let us know how it works out.
Bill
fuel pump is an easy repair. cost about $100.00 from kubota. I hopr that fixes it. Also check for a restricted muffler. It could have a loose baffle that could be coming and going.
Bill