DougWil
Well-known member
Picked up another air compressor, Dayton Speedaire from the late 70s.
Ran but very slow air buildup, had a 5hp Baldor single phase motor, so for $50 I couldn't go too far wrong.
Anyways, the pump is a V twin Japanese made, apparently only made for Grainger back in the day, 3Z960. No parts available from Grainger or any other air compressor parts supplier that I have tried.
Criminal, I tore it down to find out what is wrong with it. Absolutely beautiful machine work. Alum rods with inserts, perfect bores, tapered roller bearings...and not repairable.
Had a bad reed valve, probably could use a hone and new rings, instead into the scrap pile.
I went through this on a Dayton bandsaw a few years back, same story.
Ran but very slow air buildup, had a 5hp Baldor single phase motor, so for $50 I couldn't go too far wrong.
Anyways, the pump is a V twin Japanese made, apparently only made for Grainger back in the day, 3Z960. No parts available from Grainger or any other air compressor parts supplier that I have tried.
Criminal, I tore it down to find out what is wrong with it. Absolutely beautiful machine work. Alum rods with inserts, perfect bores, tapered roller bearings...and not repairable.

Had a bad reed valve, probably could use a hone and new rings, instead into the scrap pile.
I went through this on a Dayton bandsaw a few years back, same story.
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