I inherited my grandad’s big old 2-cylinder, 220-volt, 35 gallon horizontal air compressor he had for many years (no rust in tank).  After a few more years, I recently decided it was time to plug it in and build a real shop air system instead of my portable Bostich.

I had to rewire the plug and supply wire (he was a scrounger), add a new guage, and replace the unloader valve.  Seemed to start fine.  I raised it into my garage attic, plumbed it all in, but just could not get it to build more than about 50 psi.  It would get hot, and slowly climb to maybe 70 psi, but took forever.  Been about a week of diddling and noodling.

Could not figure out why!  This morning I decided to go ahead take the cylinder head off and look at rebuilding the valves.  Unbolting it, I went down and disassembled all four valves, cleaned and re-lapped the discs.  Figured I’d make a new head gasket, so I went upstairs to look at the gasket still on the cylinder block to make a pattern.  Immediately, I realize the head gasket was in bad shape between the cylinders.

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What was happening, above about 20-30 psi, the cylinders simply pumped air mostly back-and-forth between themselves through the torn gasket.  Made a new gasket, and bolted it all back together.

Yee-hah – got pressure now!

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Here’s the disribution set-up I built – all Harbor Freight stuff.  Air line comes in thru the garage ceiling from the big ol’ compressor , then a dump leg, then the water separator and regulator.  A tee lets me pull off dry air to two drops in the garage, and then through the wall to a reel in my shop (through the door).  Oiled dry air goes through a lubricator to the red hose reel, for hot rod garage tools.

Wanted a good set-up for a long time – really pleased with this

Forrest