Repairing a Central Pneumatic 3 gallon
oilless air compressor Model 97080

Several years ago I bought a cheap air compressor when I was building a
garage. I'd never had a compressor before, and I was embarrassed to realize how much I could have used one all my life.

This air compressor is cheap and considered basically disposable, but I'm a frugal kinda guy and hate to see waste. It performed well enough through my entire project (in retrospect, I should have bought a bigger machine for this use) but eventually stopped working. The motor ran, but the pump wasn't compressing air. I took it apart, and found the problem. A sliver of the soft rubber piston ring had ripped away.

At first I assumed that the solution was to find a replacement ring. No joy. Nobody carries rings or even rebuild kits for these. So I went back and looked further. I should have realized this, but the real problem was not an adequate pump piston seal - it was that the broken strip of rubber ring (C) was jamming one of the reed valves open. I cleaned it out, reassembled - and yippie, working pump. It's not as efficient as it once was, but it works.

The steps:
1. Open air relief valve, unplug unit, remove plastic cover.
2. Unscrew four long screws holding down top of cylinder (A), and loosen nut at bottom of outlet pipe (B).
3. Carefully disassemble components, clean, and reassemble. Note that the top reed valve assembly properly goes in one orientation only, two small pins guide you.
4. Reassemble (don't overtighten long screws) and you are done.

Lincoln Cushing
Berkeley, California, Father's Day 2016

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