Graco 166512 Washer Backup – Detailed Information
Compatible Machines
This Graco 166512 Washer Backup is used in specific Graco pump assemblies. The sprayers listed below are the common models that use pump series where this washer appears in the parts breakdown.
- Graco Pump Model 307430 (used in select contractor-grade airless sprayers)
- Airless sprayers using the same pump series that call out part number 166512 in their breakdown
Product Description
The Graco 166512 Washer Backup is a precision-made support washer used inside the fluid section of Graco airless paint sprayers. It stabilizes the packing stack, prevents seal extrusion under high pressure, and helps maintain long-term pump reliability.
Key Features
- Provides stable backing support for packings and seals
- Designed for high-pressure fluid sections
- Prevents packing extrusion and premature wear
- OEM-grade replacement for consistent performance
Technical Details
| Part Number | 166512 |
| Part Type | Washer Backup |
| Function | Supports packings and maintains alignment in pump assembly |
| Location | Fluid Section / Pump Assembly |
Frequently Asked Questions
It provides structural support behind the packings, ensures compression stability, and prevents seal extrusion during high-pressure operation.
The best method is to check your sprayer’s parts breakdown. If the pump section diagram includes part number 166512, the washer fits your unit.
Yes, it is recommended to replace the backup washer during any full packing or fluid section rebuild to maintain proper pump performance.
