Description

The EMAX Silent Air ESP10V120V1 is a 10 HP, 120-gallon two-stage vertical air compressor built for continuous-duty shop and industrial use. It pairs a V4 four-cylinder cast-iron pump (pump model APP4V1043TP) with a 230V single-phase motor and magnetic starter, delivering 38 CFM and a 175 PSI maximum working pressure from a vertical 120-gallon ASME tank.

Two features define this unit. First, the patented Silent Air silencer system, which targets the loudest part of any compressor — the air intake — to run measurably quieter than a comparable open compressor. Second, a true pressure-lubrication system that feeds oil to every bearing point, the same approach used on continuous-duty engines, for longer pump life under heavy load. The pump carries an estimated 70,000-hour service life and the unit is ETL, ASME, and CRN certified.

Features

Silent Air Patented Noise Suppression

Intake noise is the loudest source of compressor sound, so the Silent Air silencer is engineered to suppress it at the source. The design uses noise-reducing baffle plates and high-capacity filter media, and is built to run at or below conversational volume — a design target of up to 50% quieter to the human ear, where each 10 dBA drop equals a halving of perceived loudness. Unlike enclosed cabinet systems, the silencer keeps the pump fully accessible for routine service.

Pressure-Lubricated Pump

A rear-mounted gear-driven oil pump generates positive oil pressure and delivers a continuous flow of oil to every bearing point, keeping bearings cool and extending pump life. The crankshaft and connecting rods are rifle-drilled (gun-drilled) for direct oil flow to high-friction wear points, an automotive-style spin-on oil filter keeps the oil clean, and a liquid-filled analog gauge lets the operator monitor oil pressure directly. Unlike splash-lubricated pumps, pressure lubrication places oil precisely where it is needed — the more effective method for high-stress, continuous-duty operation.

100% Cast Iron Construction

All major pump components are cast iron rather than aluminum, for durability and rigidity under high-duty-cycle compression: the crankcase, cylinder heads, cylinders, connecting rods, crankshaft, and high-pressure piston. There are no aluminum sleeves beneath the paint. The low-pressure pistons on this two-stage pump are aluminum by design, since they operate under low stress (around 45 PSI).

Cast Iron Flywheel

The Eaton-built pump uses a heavy-duty cast-iron flywheel whose added mass stores kinetic energy to reduce amp draw and overall energy use. The 10 HP pump runs a 20-inch flywheel with two B-style groove belts for a larger belt contact area and longer belt life, and the flywheel is cast with large cooling fins to pull heat off the pump.

Piston and Connecting Rod Design

The high-pressure pistons are cast iron to withstand heavy loads and resist cylinder scoring. The connecting rods are CNC-machined solid cast iron for maximum rigidity, with replaceable bearing inserts and wrist pins that make the rod assembly fully rebuildable rather than throw-away.

Each piston uses a four-ring design instead of three: two oil-control rings clear excess oil on the downstroke and two compression rings seal under compression to prevent blow-by. The rings are engineered to overlap, which maximizes sealing, reduces oil carryover, and extends ring life. A rifle-drilled oil port carries oil through the crankshaft and up the rod to the piston pin and bearing for continuous lubrication.

Oil Pump

The automotive-style gear oil pump pressurizes the crankshaft bearings and the upper connecting-rod assembly. A bleeder valve allows quick priming, an adjustable regulator sets oil pressure across the RPM range, the liquid-filled gauge gives clear readings during operation, and the spin-on filter removes debris to extend pump service life.

Disc Valves

The pump uses CNC-machined concentric-ring (disc) valves, precision surface-ground for sealing and long service life. Disc valves are more durable than the feather or reed valves used on many pumps, and service is simple — remove the retainer, lift out the valve for inspection, and reinstall within minutes. All valves are engineered to support an automatic head-unloader system.

Cast Iron Cylinder Heads

The cylinder heads are solid cast iron, not aluminum, for durability and rigidity under demanding conditions. Tapped holes provide superior thread strength, and the disc-valve design holds a secure head-gasket seal without retorquing.

Cast Iron Cylinders

The cylinders are CNC-machined cast iron with deep cooling fins to maximize cylinder cooling under high-duty-cycle operation. The precision bore holds concentricity to reduce oil carryover, deep-bored and threaded holes allow proper head torque, and every bore is precision-honed for easier break-in and longer ring life.

Continuous-Run Head Unloaders

Head unloaders are recommended for electric units running at 40% or higher duty cycle. They relieve the intake valve during operation, holding it open so the piston keeps cycling without compressing — this circulates cool air through the cylinder, reduces wear and heat, and protects the motor and magnetic starter by minimizing repeated starting under load.

Dual-Bolt Belt Tensioner

A dual-bolt belt tensioner makes belt adjustment precise and repeatable, holding proper alignment and tension to reduce wear and extend belt life. Pry bars are no longer needed to tension the belts.

Pump Riser

A pump-mounting-plate riser lifts the pump to allow 360-degree airflow from the flywheel across the oil reservoir and underneath the pump, for maximum cooling.

Automatic Tank Drain

A dual-timer electric auto drain expels moisture and condensate from the receiver tank automatically, with an adjustable interval from 1 to 45 minutes and an adjustable open duration. An air muffler is included for quiet draining.

Specifications

Warranty

The ESP10V120V1 carries a 1-year standard warranty covering the compressor against defects in material, workmanship, and parts from the date of delivery, including one year of warranty labor from an authorized technician. Warranty parts ship with ground freight covered for the first six months.

Coverage can be extended to a full 5 years by registering the compressor and following the EMAX extended-warranty plan, which requires using EMAX SMART OIL and following the published maintenance schedule (break-in oil changed within the first 70 hours, then on the scheduled interval). The matching service kit for 5–10 HP Silent Air electric models is EFKIT008AWBS (sold separately).

FAQ

How much air does it deliver, and at what pressure?

The pump delivers 38 CFM, and 34 CFM at its 175 PSI maximum working pressure.

What electrical service does it need?

It runs on 230V single-phase power, draws 52.9 full-load amps at a 1.15 service factor, and a 60-amp breaker is recommended. A magnetic starter is included.

Can it run continuously?

Yes. The unit is rated for continuous run and supports automatic head unloaders, which are recommended for duty cycles of 40% or higher. Its rated duty cycle is 60%.

Is the pump cast iron or aluminum?

All major pump components — crankcase, cylinder heads, cylinders, connecting rods, crankshaft, and high-pressure piston — are cast iron. Only the low-pressure pistons are aluminum, by design, because they operate under low stress.

How is the pump lubricated?

It uses pressure lubrication: a gear-driven oil pump feeds oil through rifle-drilled passages in the crankshaft and connecting rods, with an automotive-style spin-on filter and a liquid-filled oil pressure gauge.

What certifications does it carry?

The compressor is ETL, ASME, and CRN certified.

This compressor ships freight on a pallet (approximately 1,116 lbs crated). To schedule delivery or ask about freight options, contact sales@mygaragesupplies.com or call 307-381-1810.

Documents

Piston Compressor Manual (PDF)
Warranty Statement (PDF)