

Part 862-003 is a 3/8-inch flat washer used in critical valve (CV) assemblies on compatible airless sprayers. It distributes load evenly under bolt heads and nuts, preventing damage to mating surfaces and maintaining proper clamping force. This washer restores secure fastening and reliable sealing when original washers become crushed, deformed, or corroded.
| Part Number | 862-003 |
|---|---|
| Part Description | Flat Washer CV 3/8 |
| Brand | Genuine replacement |
| Fits | Hydra M / Hydra Pro series |
| Condition | New |
The 862-003 flat washer is a precision-engineered component designed for use in critical valve (CV) assemblies on Hydra M and Hydra Pro airless sprayers. While often overlooked, washers play an essential role in maintaining proper fastener tension and preventing component damage. This 3/8-inch washer features carefully controlled inner and outer diameters, as well as consistent thickness, ensuring that it seats properly under bolt heads and nuts without interfering with surrounding components. The "CV" designation indicates its use in valve assemblies where reliable clamping force is essential for maintaining seals and preventing fluid bypass.
In high-pressure hydraulic and fluid systems, vibration, thermal cycling, and pressure fluctuations can cause ordinary hardware to loosen over time. The 862-003 washer helps maintain clamp load by providing a smooth bearing surface that allows fasteners to achieve proper torque without galling or digging into softer housing materials. It also distributes the clamping force evenly across a wider area, reducing the risk of surface deformation that could lead to leaks or misalignment. Manufactured from carbon steel with appropriate corrosion resistance, this washer withstands the harsh environment of paint and coating applications, including exposure to solvents and cleaning agents.
During routine maintenance or overhaul of Hydra series sprayers, inspecting all washers for signs of deformation, crushing, or corrosion is recommended. A crushed or deformed washer loses its ability to maintain proper preload, which can allow fasteners to loosen and lead to fluid leaks or component movement. In valve assemblies, even minor loosening can disrupt the sealing surface alignment, causing internal leakage and reduced pump efficiency. Replacing worn or damaged washers with genuine 862-003 components ensures that original equipment specifications for hardness, dimensions, and finish are met. While washers may seem like minor parts, they are critical to the long-term reliability of the equipment, and using substandard replacements can lead to fastener failure or fluid leaks that cause downtime and safety hazards.
| Load distribution | Spreads clamping force under bolt heads and nuts |
|---|---|
| Surface protection | Prevents galling and damage to mating surfaces |
| Torque retention | Helps maintain proper preload under vibration |
| Sealing support | Maintains alignment of valve components for leak-free operation |
| Visible deformation | Crushed, bent, or dished shape from over-torquing |
|---|---|
| Corrosion | Rust or pitting that compromises thickness or surface |
| Fluid leakage | Leaks at bolted joints may indicate washer failure |
| Fastener loosening | Recurring loose bolts suggest washer has taken a set |
This flat washer (part 862-003) is designed for use in the following airless sprayer models. Always verify fitment with your machine's parts diagram.
| Series / Model | Component |
|---|---|
| Hydra M and Hydra Pro 2000_4000 | flat washer CV 3/8 |
| Hydr M nad Hydra Pro Super | flat washer CV 3/8 |
| 0528925N_2000_4000 | flat washer CV 3/8 |
When servicing fasteners, consider inspecting these companion parts.
Inspect threads for stretching or damage; replace if worn.
Check locking features; replace if they no longer provide resistance.
Leaks at bolted joints often require both new washers and new gaskets.