Graco 100639 Washer Lock

Compatible Machines – Graco 100639 Washer, Lock

Listed below are the Graco assemblies/systems where part 100639 is specifically referenced. This lock washer is also used anywhere your Graco equipment parts diagram calls out 100639.

• Fluid Pressure Regulator – Model 217576 (hardware list specifies 100639 as an external shake-proof 3/8″ lock washer)
• ProBell Cart System (industrial finishing system; parts list references 100639 lock washers in multiple sub-assemblies)
• Any Graco unit that explicitly lists 100639 in its exploded parts diagram or service manual (verify in your model’s parts list).

About the Part

The Graco 100639 Washer, Lock is an external shake-proof lock washer in a nominal 3/8″ size, used to resist loosening from vibration and load cycling in Graco equipment assemblies. As an OEM hardware component, it helps maintain proper clamp load and safe operation in high-pressure environments.

Key Features

• External shake-proof design for enhanced anti-vibration performance
• 3/8″ nominal size for bolts/nuts of the same size where specified
• OEM Graco specification for fit, hardness, and reliability
• Suitable for regulators, spray systems, and brackets where lock retention is critical

Specifications

Installation Notes

• Replace the lock washer whenever you remove its fastener to maintain locking performance.
• Confirm the fastener is the correct 3/8″ size for this washer at the specified location.
• Tighten to the torque value specified in your model’s manual; do not over-compress the washer.
• Inspect for deformation, cracks, or flattening—replace if in doubt.
• Use only genuine OEM hardware where safety and warranty compliance matter.

Frequently Asked Questions