Quoted from Joel Weiss

Ours works exactly the opposite to this; I was convinced that the green was the airbag pressure and the orange the brakes.   Now I have no idea.

Oops, sorry Joel I mistyped....it's the green that drops and he orange stays up.  Galloping senility takes it toll again.

Dick and Pat

Just to clarify, in many places the law for truckers is to purge water and oil daily when setting out and every eight hours if doing more than eight hours in a day.  The idea is that oil in the valves will gum up the brake action and water will cause rust, so leaving either in your system for any longer may cause you not to have brakes when you want or need them.

If you have a dryer, you are really checking for a failure of the dryer and filter as any water in the tank means your dryer needs immediate attention.  When purging make sure you drain all the air from the system, as the purge port is small and air flow can hold back the water and oil so that you think it's dry when it's not.

I recognize I'm being sloppy on this (should be more conscientious) and only do it once a week. In my view leaving it any longer than a week is suicidal.

Keith,
Yes you can drain any water from the tanks with the valves in the filter bay. A small amount of oil in the air tanks is not a problem, however if you have a substantial amount of oil in the tanks you should look at replacing the air compressor and servicing the air dryer if you have one.

All of the oil in you air system is coming from the compressor, so it will be a judgment call as to how much oil is to much because all compressors will use some oil. Oil will lower the efficiency of the air dryer (if equipped) as well as the oil that the air compressor is using is engine oil, so you have to keep in mind that your engine is not burning all of the oil when it is low but the compressor is using it.

Gerald

Actualy I was told to add oil to the air.  With the air drier I thought that odd.  Thanks for the answere!
Keith

Hmmm, is there a standard use of the orange and green lines, front and rear, brakes and bags, no real meaning at all...

Gil
08 Contessa

Mike, here are the pix I promised;  as noted, they advise purging at least monthly - admittedly I haven't followed that schedule, but the coach and air system hasn't been used much lately.  My set is in the streetside rear "bay", but many models may have them elsewhere, including the generator compartment up front.  As far as that accessory air port goes (next to the 4 purge valves), having it in that rear bay is a super pain if you are a tow truck driver trying to hook your truck air up to the coach.

Quoted from mykee50

So when you drain these, do you open all 4 petcocks at once and let it bleed all the way down?

Yup. You need to get all the air out of the tanks or you don't really know if there is oil and water in the tank.

Quoted from Keith Moffett

Actualy I was told to add oil to the air.  With the air drier I thought that odd.  Thanks for the answere!
Keith

Keith, you add oil if you are running air tools off the air supply. Specifically high-speed rotary stuff such as grinders and drills, If you are painting, you don't want any oil at all, at all.

Just a safety note!

When you open the valves make sure you don't have any body parts in front of the outlet. If a valve upstream decides to let go with the pressure change, the pieces will come out the end of the pipe at supersonic velocities. You wouldn't be the first guy killed that way.