1996 FLD 120 low air warning/ N14 coolant pressure

1996 FLD 120 low air warning/ N14 coolant pressure
Posted: Sun Apr 4, 2010 12:30:22 PM

I have a 1996 Freightliner FLD 120 the low air buzzer quit working but I still get a warning light on the dash. I am sure the low air switch is okay. Can anyone tell me where the buzzer is located so I can get it replaced or see if the wires came loose.

Also same truck has a cummins N14 460E. I am getting pressure in the coolant system after the truck has been shut down for days and is cool. Recent oil change and oil sample shows no coolant in the oil. I have flushed the coolant system and had no signs of oil in the coolant. Could this still be a bad head gasket or could it be a bad air compressor head pumping air in to the coolant lines? Any way to do an easy test?

RE:1996 FLD 120 low air warning/ N14 coolant pressure
Posted: Sat Apr 17, 2010 12:27:52 PM

I may be wrong on this one, but I think the buzzer is built into the vigil bar. So if the buzzer is out the vigil bar would need to be replaced. I will double check on this and make sure of this information.

It could be the headgasket, a kit can be purchase from napa that can check for combustion gasses in the coolant. It coudl be the compressor. The other item that would cause it depending on the model of your truck is an air operated heater control valve. If your rear of front heater control valves have wires going to them, this would not be the case. The water control valves that had airlines controling them would sometimes leak air into the coolant.

http://TruckMechanicTips.com

RE:1996 FLD 120 low air warning/ N14 coolant pressure
Posted: Mon May 31, 2010 7:04:01 PM

You are correct about the buzzer, most people would not know that., truckwires.com