I think the compressor would definitely run hotter with the radiator between the pump and the check valve of the tank.
I also believe that running hot air from the radiator then over the heads of the compressor is a robbing Peter to pay Paul situation as far as heat transfer goes.
And with the radiator upstream from the check valve the whole radiator has to unload every time the compressor cycles so you lose all that work that’s been done to the air in the radiator.
I’m sure there’s a dramatic amount of water that comes out of that radiator but much of that water would have condensed anyways in the tank in the first few seconds so you’re using this radiator to do some work that would have already been done naturally.
There’s a lot of reasons why having your after cooler after the tank is better practice.
That being said it does work but it’s just inefficient on quite a few levels.
The examples being
that you lose the volume of compressed air in the radiator every time.
The added back pressure between the pump and the tank will cause the pump to run hotter.
Much of that initial moisture would have condensed in the tank anyhow making 60% of the work it does redundant.
Cooling the radiator by blowing heat across it and then over the pumps is a robbing Peter to pay Paul’s situation.
I’m not saying it doesn’t work because it obviously does but it comes at the daily cost of efficiency and overall capacity.
I have my active after cooler about 30 ft away from the compressor.
It definitely works but in my opinion it’s not ordered correctly for the components to do the jobs that they are made to properly and efficiently.
The other factor which I don’t know will make much difference or not is that the air flow between the pump and the tank will almost be like a heartbeat pulse where the air flow after the tank will be a real steady state flow.