Product images and videos are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
Heating and Cooling› Water Pumps
Boyesen
WATERPUMP COVER & IMPELLER KIT MAGNESIUM
SKU: WPK-31AM
Moderate — 2–4 hours
Overview
Constructed from investment cast aluminum with a heat-treated 17-4 stainless steel shaft, this kit features a patented nautilus-style impeller for improved hydrodynamic efficiency. The increased coolant flow at all RPM ranges contributes to extending engine life. This kit is designed for the Yamaha YZ 125 and Yamaha YZ 125X.
Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
Fitment
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Available on iOS & Android
Specifications
| Brand | Boyesen |
| Part Number | WPK-31AM |
| Category | Engine |
Videos
Boyesen Supercooler Water Pump Cover & Impeller Kit
Boyesen Supercooler Install & Testing! (2018 CRF450R)
How to Install a Boyesen SuperCooler
Keep Your Cool Boys, Boyesen Water Pump Super Cooler Kit (Unboxing and Install)
BOYESEN SUPERCOOLER INSTALL ON YZ 250
Installing boyesen supercooler blue Ktm sxf 450 2018.5 2019 2020 WPK-45 AL + Motohose radiator hoses
Can Am Outlander Boyesen Super Cooler Impeller Cover install fixes BRP Junk
Boyesen Supercooler: The Factory Advantage
IN DEPTH: Boyesen Supercooler featuring Kenny Venarchick (MXPTV)
Boyesen SuperCooler Intro
About MOTORMIA
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Returns & Fitment
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.
Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.
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