Filling Your Tires with the
On-Board Air Compressor
If your coach is a diesel pusher it came with an on-board air compressor to power the air brakes and air-ride suspension. In addition, an
auxiliary tap is provided that can supply air to run air tools or fill your tires. The following information will help provide some useful operating
tips from one of our members to assist you with this process.
Keeping Maximum Air Pressure Output from the On-Board Compressor:
This works exceptionally well for me...I use the on board compressor to fill to or more than 120 PSI for the front tires of the RV. The
cutoff for the compressor when it cycles off is close to 145-150Lbs. So the key is to fill as the compressor cycles on and to fill even a bit beyond
what you want to reach. The problem everyone has in using the compressor is that they wait until the unit reaches max pressure and cuts off before they
start to fill. When you do this as soon as you start to fill the tank pressure immediately drops to lets say 100 lbs, but does not trigger the
compressor back on. Thus you sit there, it fills no more and you build no more pressure. So, the correct way is you get the unit to cycle on, THEN you
start filling before it reaches the cutoff. You will continue to build pressure in the tire as well as the tank until you hit the 145 cutoff point of
Now the key here is you have to have someone sitting in the driver seat tapping the break pedal to lower tank pressure to get the unit
to come on, and then radio to you to start the fill on the upswing at about 110LBS. BUT, there is an easier one person way to do this....you add a
pressure gauge to your air hose and chuck with a T fitting. Now you can let pressure go via the chuck to get the compressor to kick on. You will also
know when to start filling, lets say at the upswing starting at 110lbs or so on your gauge. The gauge will also give you some idea of the tire pressure
but will not suffice for the regular tire gauge.
Hope this helps you. As I have said, it is silly to carry a compressor when what you have will do a very nice job.
Submitted by Alan Winger (Dynamo1181) - 10/26/09
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