ON AN INSTRUCTIONAL FLT, THE STUDENT PLT & INSTRUCTOR (CFI) MADE AN ILS LOW APCH TO RWY 30R. DRG A GO-ARND (MISSED APCH)A TWR CTLR OBSVD A 'LIGHT TRACE OF SMOKE' EMANATING FM THE ENG EXHAUST. SHORTLY THEREAFTER, THE ACFT 'BANKED HARD TO THE LEFT AND APPEARED TO STALL.' SUBSEQUENTLY, IT IMPACTED THE GND IN APRX A 20 DEG NOSE DWN, SLIGHTLY LEFT WING LOW, ATTITUDE. IMPACT OCCURRED APRX 1000' SE FM THE DEP END OF RWY 30R. THE FUSELAGE & INBRD WING SECTIONS WERE BADLY BURNED.MINIMAL ROTATIONAL DMG WAS FND ON THE PROP/PROP SPINNER. NO PREIMPACT PART FAILURE OR MALFUNCTION WAS FND DRG AN EXAM OFTHE WRECKAGE. HOWEVER, THE 3 PSN, AUX FUEL BOOST PUMP SW (INSTALLED IAW AD 87-08-05 & BEECH SB 2033) WAS FND IN THE HI BOOST PSN. THE RESPECTIVE FUEL TRUCK HAD BEEN DRAINED FOR MAINT BFR SAMPLES COULD BE OBTAINED. MAINT PSNL NOTED PARTICU-LATE IN THE FUEL, BUT NONE WAS FND IN THE ACFT FUEL SCREENS. AFTER MINOR REPAIRS, THE ENG STARTED & OPERD NORMALLY. THE FLT MANUAL PROHIBITS USE OF HI BOOST, EXCEPT WHEN THE ENG DRIVEN PUMP FAILS AS EVIDENCED BY ZERO FUEL FLOW.