As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING WALKAROUND NOTED FUEL LEAKING FROM BOTTOM OF NR 2 ENGINE COWLING. EVIDENCE OF LEAK NOTED BELOW THE NR 2 ENGINE. GROUNDED-YES. OPENED COWLING FOUND STATIC FUEL DRIPPING FROM MAIN OIL HEAT EXCHANGER PAD DRAIN 36 DPM NOTED. LEAK WITHIN LIMITS, REF B737-800 AMM 71-71-00. DEFERRED PLT FOR 25 FLIGHT CYCLES. REMOVED AND REPLACED MAIN OIL FUEL HEAT EXCHANGER, REF AMM 79-21-02.