[77newell]

The Gast compressor has check valves built into the head so no backward flow will occur unless the valves are leaky in which case the compressor is going to work awfully hard to do its job.

The idea of some leakage allowing an easier start requires a leak between the pump and the check valve; I'm thinking such a leak would hard to calibrate so that it leaks enough to allow an easy start and is small enough not to compromise the capacity of the compressor. The other hard part will be maintaining that flow rate over time.

My 93 coach never had a check valve external to the Gast. So far there have been no problems - but heck, tomorrow it will all blow up just to prove me wrong.

The other thing to consider is the pressure needed to inflate tires. Unless the compressor turns on at more than the needed pressure in the tires it is very frustrating trying to inflate tires. The Gast allows me the function of airing up the compressed air system in the coach but is essentially useless for my 115psi tires when its turn on setting is 90psi. I bought a separate small compressor for the tires and it can also back up the Gast.

The only way to combine the functions would be to install a 150psi compressor and then have a branch off it with a reliable regulator connected to the coach system, and then a connection for the tires. This approach might require a tank mounted with this compressor to stabilize the operation. If my coach didn't already have a Gast type system I probably would go this route, but since it did the extra compressor was easier.