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Graco 17J878 Ball Knocker Kit

5/5 (1 review)
$38.72
$41.90
Save 8%
In Stock
Part #: 17J878

The Graco 17J878 Ball Knocker Kit is a genuine OEM replacement that helps maintain smooth push-prime operation and consistent fluid flow in ProX series airless sprayers.

  • Fits Graco Magnum ProX17 & ProX19 models
  • Helps clear inlet valve buildup
  • OEM Graco part for reliable performance
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Genuine OEM Part Fast Shipping (Order by 1 PM CST) Easy Returns

Compatible Machines for Graco 17J878 Ball Knocker Kit

Machine Model Machine Type
Graco Magnum ProX17 Electric TrueAirless Sprayer (Stand) Airless Paint Sprayer
Graco Magnum ProX17 Electric TrueAirless Sprayer (Cart) Airless Paint Sprayer
Graco Magnum ProX19 Electric TrueAirless Sprayer (Stand) Airless Paint Sprayer
Graco Magnum ProX19 Electric TrueAirless Sprayer (Cart) Airless Paint Sprayer

The Graco 17J878 Ball Knocker Kit is an OEM replacement designed to maintain fluid flow by helping clear build-up around the inlet valve in your sprayer’s pump. By ensuring reliable push-prime action, it supports consistent spray pressure and reduces downtime caused by clogging or resistance. This part is engineered for use in multiple ProX series electric airless sprayers for dependable performance. :contentReference[oaicite:0]{index=0}

What’s Included in the 17J878 Kit

  • Ball knocker assembly designed to dislodge buildup at the inlet valve
  • Spring mechanism to provide responsive push-prime action
  • Installation label for correct identification and alignment

Key Benefits of the 17J878 Ball Knocker Kit

  • Restores push-prime function by clearing debris and improving valve action
  • Enhances equipment uptime by reducing clog-related downtime
  • OEM quality fit engineered for ProX17 and ProX19 sprayers
  • Durable design stands up to jobsite conditions and repeated use

Installation Tips

Before installing the 17J878 kit, releive system pressure and remove fluid from the sprayer. Access the pump assembly, remove the old ball knocker and spring, and insert the new components. Ensure the label is positioned as per manufacturer guidance to maintain proper function and longevity.

Frequently Asked Questions

The Ball Knocker Kit helps dislodge debris and buildup around the inlet valve, allowing the push-prime mechanism to function smoothly and maintain consistent material flow through the pump. :contentReference[oaicite:1]{index=1}

Yes. The 17J878 Ball Knocker Kit is designed for several Graco ProX electric airless sprayers, including ProX17 and ProX19 TrueAirless models in both stand and cart configurations. :contentReference[oaicite:2]{index=2}

No. The ball knocker kit is a direct replacement and installs within the existing pump assembly with no additional parts required.
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5
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L
Picked this up to replace a worn part and this 17J878 Ball Knocker Kit and it solved the issue we were having right away. Part #17J878 matched exactly. Saved us a trip to the dealer.

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