Draining the water out of the air tanks

the pull cord is probubly your airtank drain but if you dont want to pull on it to find out ask a freightliner dealer. you should drain your air tanks daily even in the summer. the schneider procedure is to drain at pretrip and every break. thats sometimes 5 times a day but better to drain them more often than have your brake lines freeze up and you cant stop.

 

Check with the shop for the locations if the manuals aren;t still in the truck, but you should have more than one drain on the truck. Usually, they will have 2-3 air tanks, and each of them will need to be drained. I don't drain at each stop, but usually hit the tanks when I am refueling, which means at worst every other day. My truck hs a tendency to be a "dry" truck, and makes very little liquid in the air system. I have driven other trucks that just liked to make moisture, and they needed to be drained daily.

 

yea, i check mine for moisture daily but rarely ever get anything but MAYBE a slight mist for the first 1/2 second. i guess it has a good drier?

 

yep mine doesn't seat properly now and will slowly loose pressure overnight. (i sprayed it with windex and saw bubbles)

 

Many older trucks will actually have an oily mist come out with the water vapor when draining the air tanks. I forgot what this signifies though. I know it aint good. Maybe 1 of the other fellas can chime in with what causes oily residue to accumulate in the air tanks.

 

Even with an air dryer you should drain the tanks daily. We would always drain the tanks during post trip but our post trips were everyday. If you do do it at post trip and have the old type screw valve don't leave the drain open and walk away.

 

If you get oil when you drain your tanks, your compressor is about to go out. Also, air dryers have a filter, if you have a dryer and get lots of moisture, you need a new air drier filter.

 

How do you drain the tanks on an older freightliner Columbia? I have looked and looked under there for some valves or levers or anything that would remotely look like would be it.. Can't find anything. pretty sure our trucks have never been drained. Winter is coming up so just thought I would ask.