SIMPSON Manifold Replacement Kit for OEM Technologies Pumps 7113804 — Aluminum Block, Integrated Unloader & TRV

The SIMPSON Manifold Replacement Kit (7113804) is a complete aluminum manifold assembly that replaces the manifold on OEM Technologies axial cam pumps 510028 and 510030, including valves, unloader, thermal relief, and fittings for fast pump restoration.

If your pressure washer pump is leaking, losing pressure, or the soap injection or unloader has failed, swapping in this factory-style manifold restores core functions without buying a new pump. The kit ships with preassembled valves, seals, mounting hardware, a soap hose screen, an integrated unloader, and a thermal relief valve (TRV). It uses a 3/4-inch garden-hose low-pressure inlet and an M22 high-pressure outlet, and the block is machined from aluminum for corrosion resistance and reliable service life.

How does this manifold kit get my pressure washer running again?

Installed as a direct replacement for the original manifold on specified OEM axial-cam pumps, the kit rebuilds critical fluid pathways and control components. You’ll restore pressure routing, soap injection, unloader operation, and overtemperature protection in one service step.

• Preinstalled inlet/outlet fittings: 3/4" garden hose inlet and M22 high-pressure outlet
• Integrated unloader re-establishes bypass and safe unload function
• Thermal relief valve reduces risk of heat-related damage
• Soap hose screen and valves included to restore detergent delivery

Which pump models and setups is the 7113804 manifold compatible with?

This assembly is made to match the OEM specifications for axial-cam pumps used in many SIMPSON and OEM Technologies pressure washers. Confirm your pump model number before ordering to ensure fit and performance.

• Designed for OEM Technologies pump models: 510028 and 510030
• Direct-fit replacement—no machining or adapter fittings normally required
• Mounting hardware included for straightforward installation
• Works with standard garden-hose supply and M22 high-pressure hoses

What components and materials are included and why they matter?

The kit arrives with all wear and control parts that typically fail first, so you replace the manifold and its working internals at once. The aluminum body balances weight, corrosion resistance, and heat dissipation for dependable service.

• Aluminum manifold body for durability and heat handling
• Preinstalled valves and seals to reduce installation time and leaks
• Integrated soap injection port with screen to protect valves from debris
• Thermal relief and unloader included to safeguard pump under heavy use

How difficult is installation and what tools or skills are needed?

Installation is intended to be user-serviceable for mechanically skilled homeowners or service technicians familiar with pressure washer pumps. Basic hand tools and attention to torque and sealing surfaces are required.

• Requires basic hand tools: wrenches, screwdrivers, and thread sealant
• Replaces the factory manifold using included mounting hardware
• Follow manufacturer torque specs and inspect mating surfaces for flatness
• If unsure, use a qualified service technician to avoid leaks or damage

Who is this for: The SIMPSON 7113804 manifold replacement kit is for owners and service shops maintaining pressure washers built around OEM Technologies axial cam pumps 510028 or 510030. It’s ideal for customers who want a factory-style repair solution that restores soap injection, unloader function, and thermal protection without sourcing individual parts. Choose this kit if you need a reliable, ready-to-install manifold assembly to get commercial or residential power-washing equipment back into service quickly.