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Craftsman
Water Pump

Model # 3902521 Official Craftsman pump

Here are the diagrams and repair parts for Official Craftsman 3902521 pump, 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 34 parts  |
Pump Housing O-ring (replaces U9-200) U9-399
#6

Pump only diagram

Pump housing o-ring (replaces u9-200)

Part #U9-399

This item is not returnable
$28.33 | 
15% OFF Phone Price : $33.33
In Stock
Hose Clamp U19-55SS
#5

Tank only diagram

Hose clamp

Part #U19-55SS

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

Pump Body Gasket J20-18
#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.
This item is not returnable
$9.99 | 
9% OFF Phone Price : $10.99
In Stock
Captive Air Tank Inlet Flange (replaces U131-422p) U31-446P
#2

Tank only diagram

Captive air tank inlet flange (replaces u131-422p)

Part #U31-446P

$43.09 | 
10% OFF Phone Price : $48.09
In Stock
0-ring U9-226
#19

Pump only diagram

0-ring

Part #U9-226

$10.71
In Stock
Pump Shaft Seal 17351-0009
#2

Pump only diagram

Pump shaft seal

Part #17351-0009

This item is not returnable
$8.89 | 
10% OFF Phone Price : $9.89
In Stock
Switch 2782
#28

Pump only diagram

Switch

Part #2782

Replaced by #TC2153-P2

?
Manufacturer substitution
This part replaces 2782. Substitute parts can look different from the original.
$59.89 | 
8% OFF Phone Price : $64.89
In Stock
Pump Impeller Housing Clamp C19-54SS
#10

Pump only diagram

Pump impeller housing clamp

Part #C19-54SS

$231.69 | 
$10.00 OFF Phone Price : $241.69
In Stock
Pump Check Valve (replaces N12-12p) N166-5P
#20

Pump only diagram

Pump check valve (replaces n12-12p)

Part #N166-5P

$123.89 | 
7% OFF Phone Price : $133.89
In Stock
Pump Impeller J105-40PE
#8

Pump only diagram

Pump impeller

Part #J105-40PE

$139.59 | 
7% OFF Phone Price : $149.59
In Stock

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