Craftsman
Water Pump

Model #3902521 Official Craftsman pump

Here are the diagrams and repair parts for Craftsman 3902521 pump, as well as links to manuals and error code tables, if available.

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Owner’s manual

Showing 10 of 34 parts

Pump Housing O-Ring#6

Pump only Diagram

Pump housing o-ring

Part #U9-399
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Pump Shaft Seal#7

Pump only Diagram

Pump shaft seal

Part #U109-6A
Replaced by #U109-6B
?
Manufacturer substitution
This part replaces U109-6A. Substitute parts can look different from the original.
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Pump Body Gasket#15

Pump only Diagram

Pump body gasket

Part #J20-18
Replaced by #J20-18C
?
Manufacturer substitution
This part replaces J20-18. Substitute parts can look different from the original.
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Pump Pressure Switch Tube#17

Pump only Diagram

Pump pressure switch tube

Part #U37-673P
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Pump Check Valve#20

Pump only Diagram

Pump check valve

Part #N166-5P
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Pump Rear Body#5

Pump only Diagram

Pump rear body

Part #L176-47P
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Pump Hose Fitting, 90-degree#18

Pump only Diagram

Pump hose fitting, 90-degree

Part #U111-212T
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Pump Shaft Seal#2

Pump only Diagram

Pump shaft seal

Part #17351-0009
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Pump Venturi#12

Pump only Diagram

Pump venturi

Part #N32P-66
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Pump Impeller Housing Clamp#10

Pump only Diagram

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