I've been nagging my neighbor for the past 7 years to get this compressor up ang going as it had been sitting on his garage floor tucked in the corner. This compressor came out of an old Firestone shop many years ago and was driven by a 7-1/2HP 3 phase motor installed on an 80 gallon vertical tank. Since my neighbor did not have 3 phase power, he installed a cheapy single stage Craftsman compressor and 3HP 3450 RPM motor. I told him I'd help him out and order all parts necessary to get this compressor running. A new 5HP Baldor motor, Siemens 5HP mag starter, Pumptrol pressure switch, check valve, safety valves, motor sheave/bushing, and air filter were ordered. The compressor really puts out some air at very low RPM. It just purrs along and is actually pretty quiet. The Dressor nameplate on the tank states the type 5000 compressor uses a 5HP motor and operates at 770 RPM max. I ordered a 2B80SK motor sheave to obtain 770 RPM compressor speed. The only issue I've run into is that it overloads the motor and pulls 25 amps when the tank pressure reading exceeds 130 psi. Perhaps the motors used for these compressors back in the 1960's were de-rated on horsepower. The 5HP Baldor L1430T motor has nameplate amperage rating of 20.6 amps. 23.7 amps would be amperage rating at 1.15 S.F. So, I'm not thrilled. I've ordered a 2B70SK sheave to slow the compressor speed down a bit to about 675 RPM and we'll see what happens. The CFM produced will drop a bit but I don't want the motor to have a premature life expectancy either due to constant overloading. It will still be more than enough CFM to satisfy the requirements of a home workshop. My neighbor gave it a shot of paint which really set it off. Pretty close to the original paint scheme as well. He's got a little bit of touch up paint work and we'll wire up the low oil shut-down switch and install the belt guard. He should be set for many many years of reliable service.
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