Model # 921166420 Official Craftsman air compressor

Here are the diagrams and repair parts for Official Craftsman 921166420 air compressor, as well as links to manuals and error code tables, if available.

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Owner’s manual

Model diagram and schematic

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ALL PARTS

Showing 10 of 24 parts |

#KIT4

Air compressor diagram

Air compressor wheel kit

Part #E102369

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

Air compressor diagram

Companion air compressor cooling fan

Part #E100297

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

#33

Air compressor diagram

Air compressor shroud, rear

Part #E100300

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

#74

Air compressor diagram

Air compressor air hose

Part #E103623

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

#52

Air compressor diagram

Air compressor drain valve

Part #E101717

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

Companion Air Compressor Quick-connect Hose Coupler E100307

#36

Air compressor diagram

Companion air compressor quick-connect hose coupler

Part #E100307

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

#49

Air compressor diagram

Air compressor check valve

Part #E101362

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

Companion Air Compressor Intake Filter Kit E100794

#KIT3

Air compressor diagram

Companion air compressor intake filter kit

Part #E100794

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

#79

Air compressor diagram

Air compressor safety valve

Part #E102612

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

Air Compressor Vibration Isolator Pad E101037

#55

Air compressor diagram

Air compressor vibration isolator pad

Part #E101037

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 my air compressor safety valve keep popping open?

Main causes: bad safety valve, pressure switch failure…

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

Main cause: bad check valve…

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

Main cause: faulty output air pressure regulator…

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 is my air compressor not turning on?

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

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

Main cause: bad air tank pressure gauge…

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 check valve

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

Repair difficulty

Time required

15 minutes or less

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

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 # 921166420 Official Craftsman air compressor

Model diagram and schematic

SEARCH WITHIN THIS MODEL

Most common symptoms to help you fix your air compressors

Why does my air compressor safety valve keep popping open?

Why won't my air compressor tank hold air?

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

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

Why does air leak from my air compressor?

Why is my air compressor not turning on?

Why won't my air compressor build tank pressure?

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

Most common repair guides to help fix your air compressors

How to replace an air compressor check valve

How to replace an air compressor pressure switch

How to rebuild an air compressor pump

Effective articles & videos to help repair your air compressors

How to reduce air compressor noise

The unseen dangers of air compressors

How to maintain an oil-free air compressor

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