Model # 921166390 Official Craftsman air compressor

Here are the diagrams and repair parts for Official Craftsman 921166390 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 31 parts |

#NI08

All parts diagram

Tube kit

Part #E101429

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

#13

Air compressor diagram

Air compressor cylinder

Part #E101113

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

#36

Air compressor diagram

Air compressor check valve

Part #E100898

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

#NI05

All parts diagram

Craftsman handle ki

Part #E101492

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

Air Compressor Crankcase Cover Kit E101332

#NI06

All parts diagram

Air compressor crankcase cover kit

Part #E101332

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

Air compressor diagram

Air compressor valve plate assembly

Part #E100228

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

Task Force Air Compressor Pressure Regulator E100059

#55

Air compressor diagram

Task force air compressor pressure regulator

Part #E100059

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

#62

Air compressor diagram

Handle cap

Part #E101490

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

Air compressor diagram

Companion air compressor air filter

Part #E100435

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

#50

Air compressor diagram

Air compressor pressure switch

Part #E100957

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 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 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 does my air compressor safety valve keep popping open?

Main causes: bad safety valve, pressure switch failure…

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 tank hold air?

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

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 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 # 921166390 Official Craftsman air compressor

Model diagram and schematic

SEARCH WITHIN THIS MODEL

Most common symptoms to help you fix your air compressors

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

Why won't my air compressor build tank pressure?

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

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

Why does my air compressor safety valve keep popping open?

Why does air leak from my air compressor?

Why won't my air compressor tank hold air?

Why is my air compressor not turning on?

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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