NHC-250 CUMMINS FAN CONTROL AIR VALVE FOR M939 AND M939A1. WILL NOT FIT CUMMINS 8.3 TURBO ENGINES FOUND IN M939A2 SERIES TRUCKS.

FACTORY SET TO OPERATE WHEN THE COOLANT TEMPERATURE IS AT 190 DEGREES. IF YOUR FAN IS NOT WORKING IN YOUR TRUCK, THIS IS THE FIRST ITEM i WOULD TAKE A LOOK AT AND TEST.

PART # CA200046 NSN 4820-01-149-1317 ALT #s CAS190, 11669644, 4820011491317