SMA ON INST APCH HAS LOSS OF ARTIFICIAL HORIZON AND DIRECTIONAL GYROSCOPE. RADIOS ALSO DIED.

Narrative

AFTER BEING CLRED FOR THE APCH TO BRANDYWINE N99 THE ARTIFICIAL HORIZON SLUMPED OVER AND DIRECTIONAL GYRO ROTATED COUNTER-CLOCKWISE. WIND WAS 45 KTS E. RAIN WAS LEVEL 2. PHL APCH TOLD ME I WAS OFF COURSE AND TO RETURN TO MXE VOR AND FLY THE APCH OVER. THE FREQ WAS 128.40 AND I WAS GIVEN A NEW FREQ; 132.67; AND WHEN I ENTERED THIS FREQ THE RADIOS WENT DEAD. I WAS HEADED TO MXE VOR. I HAD PREVIOUSLY SET THE LOC FREQ FOR THE ILS INTO COATSVILLE (40N) IN THE STANDBY. 40N HAS 5200 FT WHEREAS BRANDYWINE ONLY HAD 2600 FT OF RWY. I WAS HAVING A VERY DIFFICULT TIME HOLDING PITCH. WHEN I SAW THE LOC NEEDLE COME ALIVE I FLEW THE ILS INBOUND; BROKE OUT ABOUT 1400 FT AND MADE A CIRCLING APCH INTO COATSVILLE. I WENT INTO THE FBO AND IMMEDIATELY TALKED WITH PHL APCH AND TOLD THEM I WAS ON THE GND AT COATSVILLE AND WHAT HAD HAPPENED. THE FOLLOWING DAY I PULLED THE FAILED RADIO AND DISCOVERED IT WAS WET AND WORKED FINE AFTER DRYING. THE 2 INSTS FAILED BECAUSE A NEW GYRO FILTER HAD BEEN INSTALLED 2 FLT HRS PREVIOUSLY AND WAS NOT TIGHTENED ENOUGH AND THE FILTER HAD ROTATED FROM VIBRATION A CUT OFF VACUUM TO THOSE INSTS. I DID NOT TRY TO ENTER THE NEW FREQ INTO THE #2 RADIO. I DIRECTED MY ENTIRE ATTN TO NEEDLE; BALL AND AIRSPD TO TRY TO LEVEL THE PITCH. I AM VERY SORRY I TIED UP PHL AIRSPACE FOR A SHORT TIME BUT I DON'T KNOW WHAT ELSE COULD HAVE BEEN DONE.