Model # EC12 Official Hitachi air compressor

Here are the diagrams and repair parts for Official Hitachi EC12 air compressor, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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Showing 10 of 71 parts |

#33

Air compressor diagram

Hitachi crankshaft

Part #881-562

The manufacturer no longer makes this part, and there's no substitute part

Air compressor diagram

Hitachi joint fittng

Part #881-552

The manufacturer no longer makes this part, and there's no substitute part

#14

Air compressor diagram

Hitachi valve plate

Part #881-556

The manufacturer no longer makes this part, and there's no substitute part

#22

Air compressor diagram

Hitachi dipstick

Part #881-469

The manufacturer no longer makes this part, and there's no substitute part

Air compressor diagram

Hitachi screw

Part #881-412

The manufacturer no longer makes this part, and there's no substitute part

#19

Air compressor diagram

Hitachi housing

Part #881-568

The manufacturer no longer makes this part, and there's no substitute part

#61

Air compressor diagram

Hitachi joint

Part #881-576

The manufacturer no longer makes this part, and there's no substitute part

#37

Air compressor diagram

Hitachi rotor

Part #881-563

The manufacturer no longer makes this part, and there's no substitute part

#12

Air compressor diagram

Hitachi screw

Part #881-551

The manufacturer no longer makes this part, and there's no substitute part

#15

Air compressor diagram

Hitachi valve set

Part #881-557

The manufacturer no longer makes this part, and there's no substitute part

Most common symptoms to help you fix your air compressors

Choose a symptom to see related air compressor repairs.

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Why does air leak from my air compressor?

Main causes: loose air tube fitting connections, bad check valve, faulty safety valve, damaged or corroded air tank, bad…

Why won't my air compressor start with a full air tank?

Main cause: bad check valve…

Why won't my air compressor build tank pressure?

Main causes: tank drain valve open or leaking air, leaky air tank, bad safety valve, worn pump seals, bad pump valve pla…

Why won't my air compressor tank hold air?

Main causes: rusted air tank, loose air tube fitting connections, bad check valve, leaky safety valve, bad tank drain va…

Why does my air compressor safety valve keep popping open?

Main causes: bad safety valve, pressure switch failure…

Why can't I adjust the output air pressure on my air compressor?

Main cause: faulty output air pressure regulator…

Why doesn't my air compressor's pressure gauge work?

Main cause: bad air tank pressure gauge…

Why is my air compressor not turning on?

Main causes: lack of electrical power, check valve failure, bad pressure switch…

Most common repair guides to help fix your air compressors

These step-by-step repair guides will help you safely fix what’s broken on your air compressor.

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How to replace an air compressor pressure switch

You can replace a broken air compressor pressure switch in about 45 minutes. …

Repair difficulty

Time required

45 minutes or less

How to rebuild an air compressor pump

If the air compressor won't fill the tank with compressed air, rebuild the pump using these steps in about 45 minutes. …

Repair difficulty

Time required

45 minutes or less

How to replace an air compressor check valve

You can replace a defective air compressor check valve in about 10 minutes.…

Repair difficulty

Time required

15 minutes or less

Effective articles & videos to help repair your air compressors

Use the advice and tips in these articles and videos to get the most out of your air compressor.

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Model # EC12 Official Hitachi air compressor

Model diagram and schematic

SEARCH WITHIN THIS MODEL

Most common symptoms to help you fix your air compressors

Why does air leak from my air compressor?

Why won't my air compressor start with a full air tank?

Why won't my air compressor build tank pressure?

Why won't my air compressor tank hold air?

Why does my air compressor safety valve keep popping open?

Why can't I adjust the output air pressure on my air compressor?

Why doesn't my air compressor's pressure gauge work?

Why is my air compressor not turning on?

Most common repair guides to help fix your air compressors

How to replace an air compressor pressure switch

How to rebuild an air compressor pump

How to replace an air compressor check valve

Effective articles & videos to help repair your air compressors

How to tell if a fuse is blown

How to reduce air compressor noise

How to maintain an oil-lubricated air compressor

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