Compressor struggling

[fizzy]

My mate's big twin compressor is struggling to build pressure and running most of the time. Mind you it is 16 years old and in daily use! Can't remember the make but it is a quality one - 3 phase with a huge tank.
Rings gone or something easy?

Is it as simple as changing rings or do the bores wear out as well?

 

[Alan Reynolds]

It's worth just lifting the head and checking the valves. Sometimes they crack or break off.

I've made new reed valves from shim of the same thickness or used carbon fibre reed material from motorbikes. All still working after years. I did use a bit of plastic coke bottle when I had one go out on site. Worked a treat for so long I forgot to do it properly.

 

[Afterimage]

It might be as simple as a failed gasket.