Compatible Machines
A definitive model-by-model list is not published for Graco 166073 Packing O-Ring. Compatibility depends on the pump/fluid section used in your sprayer. Please confirm by checking your machine’s parts manual for part number 166073 (also written as 166-073).
- Open your sprayer’s parts manual and search the packing/O-ring section for 166073.
- Match the O-ring location in your pump or valve assembly before ordering.
- If unsure, share your sprayer’s model and serial with support to verify fit.
Product Overview
Genuine OEM seal used in Graco fluid sections to prevent leaks and maintain pressure integrity. Ideal for restoring sealing performance when overhauling pumps or servicing valve groups.
| Specification | Detail |
| Part Number | 166073 (aka 166-073) |
| Item Type | Packing O-Ring / fluid seal |
| Role | Seals fluid passage to prevent bypass and pressure loss |
| Material | High-performance polymer (commonly PTFE/Teflon in equivalent listings) |
| Position | Within pump/fluid section or valve stack (refer to your model diagram) |
| Package Contents | 1 × O-ring |
Key Benefits
- Restores sealing performance to reduce leaks and pulsation.
- Helps maintain correct operating pressure and spray pattern.
- OEM-grade fit and reliability when used in the correct assembly.
Fit & Verification Tips
- Always depressurize and flush equipment before service.
- Inspect gland surfaces and grooves; clean out debris or old seal fragments.
- Lightly lubricate with a compatible fluid to avoid nicks/twisting during install.
- Reassemble to the torque values in your service manual and leak-test at low pressure first.
Frequently Asked Questions
Check your model’s illustrated parts list. If 166073 (or 166-073) appears for the pump/valve location you’re servicing, it’s the correct seal. If it doesn’t appear, do not substitute—contact support with your model and serial for confirmation.
Aftermarket options exist, but sealing performance varies by material and tolerance. For high-pressure applications and consistent results, use the OEM part specified in your manual.
Persistent fluid leaks, difficulty holding pressure, excessive pulsation, or inconsistent spray pattern usually point to worn or damaged packings/O-rings in the fluid section.
