As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE ACCOMPLISHING #1 ENG HMU AND FUEL SERVO HEATER LEAK CHECK FOUND SERVO FUEL HEATER CAP LEAKING. GROUNDED - YES. REMOVED AND REPLACED #1 ENG SERVO FUEL HEATER IAW B737-900 AMM 73-11-07 THROUGH STEP 3. E. 6. L. #1 ENG SERVO FUEL HEATER INSTALLATION TEST PASSED. NO LEAK. REF AMM 73-11-07.