Thanks Sharkry, I'll give that a try and I'll check all other places for any air to escape like the air gauge in the SPOD

 

You need to fit an air guage to the tank to see if the tank is reaching the set-point for the maximum PSI rateing of the high pressure limit. If you can't hear a leak, this will also tell you if you have a leak.

Compressor pump cycleing OFF / ON - Could be caused by a leak. Could be cause by control power ( but this would eventually stop when the tank reached full pressure ).

 

Had this problem in the previous Jeep.
I eventually found that the pressure escaped back though the ARB itself. Adding a one-way valve solved it.
The ARB should 'read' the pressure after the one-way valve.

 

Needing a "check valve" would seem to indicate a problem with the pump.

 

No problem with the compressor, this is how the ARB is made.
It is one of the best compressors. Good flow and highly reliable.

 

Then why does it leak like a siv?

 

Sorry -- what's "siv" ?

 

Its basically a screen. Or a "Sift".

I just can't see the purpose in a compressor that will not hold air?

 

I've seen quite a few compressors and water/air pumps that relied on one way valves.
The ARB backwards leak is unnoticeable under normal use (inflating a tire). The leak is tiny, probably no leak at all when it pushes air forward.

When this happened with the first ARB, the importer gave me another one, brand new - which was the same. I had him call ARB in Australia... They said what I said before:
"It's made this way. If the client insists on leaving it on 'ON', give him a one way valve."

It's now my second ARB (sold the first one with the Jeep). This time I took the twin head, portable, in a case that stores everything.
It inflates and operates pneumatic tools "flawlessly" (pun intended )

 

I understand that "check valves" are an integral part of compressors. And are a commomn point of failure in compressors. I can not speak from experience with this type of compressor. But if this is a repetitive problem with any type of compressor. And it is not manufactured to be a serviceable part. Then I would be looking for another type / brand of compressor. I expect a compressor to hold air. If it doesn't, then it's just about as worthless as a party balloon with a hole in it.