Narrative:

It was observed that the #1 engine oil temperature was in the yellow (caution) band. It was also discovered that the #1 engine fuel heat light was on with the switch in the off position. It was determined that the problem could not be fixed while airborne. An engine shutdown was determined to be the next step since the engine oil temperature was going to exceed the 15 mins time limit. When this determination was made, the aircraft had climbed to 29000 ft and was approximately 30 mi south of jax. A decision to land at jax was made. ATC was contacted and advised of the situation and an emergency was declared. Standard engine shutdown procedures were followed and an uneventful single engine landing was made at jax. At the gate, the crew was advised by maintenance that the cannon plug for the fuel heat had been disconnected by maintenance in mco by mistake while trying to fix an engine anti-ice valve problem. The anti-ice problem stemmed from the right anti-ice valve being stuck in the transit position. Maintenance was not able to fix the problem and the valve was put on MEL for departure. The cannon plug on the fuel heat was disconnected instead of the anti-ice valve which caused the engine oil temperature problem. From the first officer's seat, the #1 fuel heat light is almost impossible to tell if the light is on or off. Since the fuel heat was not used and was not suspected to be defective, it was not noticed immediately that the switch was in the off position and the valve was in the open position.

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Original NASA ASRS Text

Title: AN ACR B737-200 HAD TO DIVERT WITH AN ACFT EQUIP PROB HIGH #1 ENG OIL TEMP AND ENG ANTI-ICE VALVE STUCK IN TRANSIT.

Narrative: IT WAS OBSERVED THAT THE #1 ENG OIL TEMP WAS IN THE YELLOW (CAUTION) BAND. IT WAS ALSO DISCOVERED THAT THE #1 ENG FUEL HEAT LIGHT WAS ON WITH THE SWITCH IN THE OFF POS. IT WAS DETERMINED THAT THE PROB COULD NOT BE FIXED WHILE AIRBORNE. AN ENG SHUTDOWN WAS DETERMINED TO BE THE NEXT STEP SINCE THE ENG OIL TEMP WAS GOING TO EXCEED THE 15 MINS TIME LIMIT. WHEN THIS DETERMINATION WAS MADE, THE ACFT HAD CLBED TO 29000 FT AND WAS APPROX 30 MI S OF JAX. A DECISION TO LAND AT JAX WAS MADE. ATC WAS CONTACTED AND ADVISED OF THE SIT AND AN EMER WAS DECLARED. STANDARD ENG SHUTDOWN PROCS WERE FOLLOWED AND AN UNEVENTFUL SINGLE ENG LNDG WAS MADE AT JAX. AT THE GATE, THE CREW WAS ADVISED BY MAINT THAT THE CANNON PLUG FOR THE FUEL HEAT HAD BEEN DISCONNECTED BY MAINT IN MCO BY MISTAKE WHILE TRYING TO FIX AN ENG ANTI-ICE VALVE PROB. THE ANTI-ICE PROB STEMMED FROM THE R ANTI-ICE VALVE BEING STUCK IN THE TRANSIT POS. MAINT WAS NOT ABLE TO FIX THE PROB AND THE VALVE WAS PUT ON MEL FOR DEP. THE CANNON PLUG ON THE FUEL HEAT WAS DISCONNECTED INSTEAD OF THE ANTI-ICE VALVE WHICH CAUSED THE ENG OIL TEMP PROB. FROM THE FO'S SEAT, THE #1 FUEL HEAT LIGHT IS ALMOST IMPOSSIBLE TO TELL IF THE LIGHT IS ON OR OFF. SINCE THE FUEL HEAT WAS NOT USED AND WAS NOT SUSPECTED TO BE DEFECTIVE, IT WAS NOT NOTICED IMMEDIATELY THAT THE SWITCH WAS IN THE OFF POS AND THE VALVE WAS IN THE OPEN POS.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.