Broomwade compressor pumps.

Don`t know about the AC10,but the AC40`s have springs in both valves.Don`t look like coil springs,they are like flat plates with a maze cut out.Four of the free ends on the od curl up and hold the outside valve plate against the seat,same for the inner plate.Bit hard to describe.You will get the fright of your life when you get the price for new valves.. regards,Mark.

Thanks Mark! I get the uneasy feeling that by the end of this little episode of compressor repair, I will be the world's leading authority on the mighty AC10! What you describe on the AC40 sound like reed valves...(I knew nothing about compressor valves before yesterday). However I managed to get drawings out of Compair at the second attempt and its all become clear to me now. The AC10 had been stood idle for some time, and after consulting the drawings I prised out the encrusted valve plates and found the broken remnants of coil springs behind them. (I mistakenly thought the valve plates were the bottom of the valve guard...fool). So all I've got to do is recut the seats and get the springs and plates...maybe I should take a chair with me when I collect them. Cheers.

No,they are not reed valves,just my inability to explain it correctly.The actual valve is a flat circular ring,two off in each valve.The spring is a separate plate. regards,Mark.