I suspect mine was a lash-up job from used parts as the low pressure inlet reed valve shattered early on and did a lot of damage.  I've been battling with it ever since but I'm not yet prepared to give up on it.  Also, silicon oil is on its way for regular addition after the new rings are fitted.

Well, I'm guessing that in the long run the proper oil will be cheaper than putting in new rings all the time?

This sort of thing is what drove me to the Hills (although the CS4i had given me no trouble).

The Hills uses a proprietary silicon oil too. But only needs changing after 50 hours, and I can get it from an Aussie dealer...no need to get it in from the UK.

This stuff for the pump internals...it uses a wee drop of oil each time you run it.

Might work for you too?

Pulled the top off again and yes the rings are toast.  Also, no lube visible so it looks like I have two issues.  First, the 'superior' copper infused aftermarket rings are rubbish so I've ordered more of the genuine parts.  Second, I'm using fully synthetic 20w50 motor oil in place of the ISO100 synthetic (which is crazy expensive) and it doesn't appear to be getting past the lower ring set to the high pressure section.  

I fitted a new set of the 'special' rings lubed in silicon oil and managed to fill my bottle to 240 Bar before it slipped back to 170 (one-way valve in fill line).  Turned the compressor off and the pressure held on the display, so no leaks.  Must be rings again (sigh.....)

My plan is to fit the new rings when they arrive again lubed in silicon oil and squirt a small amount into the low pressure intake each time I use it.  If that doesn't work, I'll have to take out a mortgage to pay for some more ISO100.

The Hills is going great.

I'm very happy with it.

I did add another cooling fan (they are air cooled). There was no real need right away to add more cooling but thought that maybe one day I'd also buy a tank.  

I have taken it around to the range a couple of times...not too heavy and fits OK in the boot of the wee Suzuki Fronx.

It is a bit faster at pumping than the GX CS4i I had too.

Spendy...but I'll recoup a lot of that back one day when I sell my gear.

Extra fan as per photo. Runs off a wall wart.

I'm getting a bit fed up with my Tuxing, looks like the high pressure rings have gone again.  Last time I used it to fill my bottle it managed 310 Bar, but today it wouldn't go higher than 220.  The rings were replaced only two fills ago after the coolant pump failed and cooked the last set.

If I wasn't capable of fixing the damned thing myself it would have long gone!

Well...it arrived today.

Certainly looks to be a well made unit, and more than a tad heavier than the CS4i (well...it's about twice the weight so I won't be taking it around to the range any time soon).

Looking forward to trying it tomorrow (the 9015 needs some more puff now).

Same with the GX CS4i. You have to keep the check valves clean on them too.

The Evo 310 is similar to the CS4 in that it uses silicone oil to lube the piston (the CS4 uses silicone grease and 'eats' that during use).

The Evo 'eats' the oil during use, but sparingly. It also has the same idea of silicone rubber 'rings' as the CS4 does. 

For me the slightly greater air output and less high pressure are fine. I only go to 200 bar on the 9015.

Ask me in 5 years time if I'm still happy. I'll only be 83 then, so will be still around and kicking. 

Prior to that I had a nomad 2. If I wasn't capable of taking it apart to repair it, it would have crapped out on me a long time ago, but I made the repairs and it kept running. The nomad is still running for the new owner.

It's things like check valves that cause issues.

Thought about it all overnight.

Ordered the Hill Evo 310 today.

It will outlast me for my projected future shooting life, and then I can sell it on here to one of you (maybe 8 years time!). 

It will be a lot less drama for me compared to the CS4 as no water cooling, or grease pot worries now.

Hope I made the right move?