General Pump K7.3 Unloader 3/8" 6.6-10.8GPM 3500PSI - 1395

The General Pump K7.3 is a flow-actuated unloader valve engineered to protect your pump, regulate system pressure, and deliver a noticeably smoother trigger gun feel on professional pressure washers running between 6.6 and 10.8 GPM at up to 3500 PSI. Designed for commercial rigs that frequently push water through 200–500 ft of hose, the K7.3 eliminates the harsh kickback and spike pressure events that plague lesser unloaders. The result is smoother operation, safer equipment, and more consistent cleaning results across every job.

Why You'll Love the General Pump K7.3 Unloader

Whether you're running a fleet wash trailer, cleaning concrete flatwork, or tackling mobile detail jobs, the K7.3 unloader is built for the demands of real-world commercial pressure washing.

• Consistent working pressure at the gun – The K7.3 keeps operating pressure steady even when you add 200–300+ feet of hose or swap between different nozzle tips and surface cleaners, so you get predictable cleaning power at the gun tip every time.

• Smoother trigger operation – Because the K7.3 offers gradual pressure buildup when the gun is opened, you experience less kickback on every pull. That soft start translates to less fatigue over a full workday.

• Better pump protection – Proper bypass and pressure control help reduce cavitation, overheating, and premature pump wear. Water is redirected through a bypass to eliminate pressure in the system during bypass mode, keeping everything within safe operating limits.

• Handles demanding commercial setups – Rated for 6.6 to 10.8 GPM and up to 3500 PSI, the K7.3 matches the flow and pressure envelope of popular 5.5–8 GPM professional machines used in fleet washing, property maintenance, and agricultural cleaning.

• Reliable bypass for long hose runs – When plumbed correctly back to a buffer tank or pump inlet, the K7.3 maintains reliability across long lines without the chatter or surge common with smaller, undersized unloaders.

What Makes the K7.3 Different From Other Unloaders

Most budget unloaders use a pressure-actuated (trapped-pressure) design that waits for downstream pressure to exceed a threshold before diverting flow. That approach can feel abrupt, cause spike pressure in your lines, and add unnecessary stress to hoses and fittings. The K7.3 takes a fundamentally different approach-and the difference is immediately noticeable at the trigger.

• Flow-actuated design for smoother bypass – Flow-actuated unloaders respond to water flow changes rather than pressure changes. When you release the trigger, the K7.3 senses the drop in flow through its internal orifice and shifts a balanced piston to route water into bypass mode, producing a far smoother transition than pressure-trapping designs.

• Optimized for higher GPM rigs – The K7.3 unloader operates at 6.6 to 10.8 GPM, matching the output of popular commercial pumps. Contractors who run 5.5–8 GPM builds won't deal with the "choked" or finicky behavior of an undersized unloader.

• Stable performance with long hose lengths – When plumbed and sized correctly, the K7.3 maintains consistent performance even at 200–500 ft hose runs, countering the common idea that flow-actuated unloaders can't handle distance.

• Fine-tunable pressure adjustment – Technicians can dial in working pressure accurately at the gun using the adjustment knob or nut and a quality pressure gauge-no need to guess at PSI settings.

• Heavy-duty construction for daily use – It is built with stainless steel and brass internal components for durability, and the K7.3 features a balanced piston design without external springs. That means fewer parts exposed to fatigue, vibration, or weather, improving long-term reliability for contract cleaners, fleet washers, and property maintenance crews.

Product Details:

• Type – Flow actuated unloader valve designed for high-pressure cleaning systems.

• Rated flow range – The K7.3 unloader operates at 6.6 to 10.8 GPM, making it ideal for many 5.5–8 GPM commercial units. Systems with flow below 6.6 GPM may need a smaller K7 variant (such as the K7.2) to avoid unstable pressure behavior.

• Maximum pressure – The K7.3 unloader supports a maximum pressure of 3500 PSI, suitable for common 2500–3500 PSI professional machines.

• Temperature capability – Rated for operating temperatures up to approximately 165°F, making it suitable for both cold water and hot water pressure washers commonly used in fleet washing and grease removal work.

• Inlet and outlet ports – Inlet: 3/8-inch female BSPP/FPT. Outlet: 3/8-inch male BSPP/MPT. Always verify fittings and thread type before installing.

• Bypass port – 3/8-inch female BSPP/FPT. The bypass connection must route water back to a buffer tank or pump inlet with minimal restriction to maintain proper operation.

• Orientation and mounting – Can be block-mounted directly to the pump head or remote-mounted on a bracket. Use secure, vibration-resistant hardware to prevent loosening during operation.

• Included components – The unloader body, adjustment knob or nut, spring assembly, internal balanced piston, and a bypass orifice. Rebuild kits are available separately.

• Weight – Approximately 4.5 lb in standard configurations.

Frequently Asked Questions

• Can I run 200–300+ feet of hose with a K7.3 unloader? Yes. When properly matched to your pump's GPM and PSI output, plumbed with an unrestricted bypass, and adjusted with a gauge, the K7.3 is widely used with 200–500 ft hose runs on professional rigs without issue.

• What size pressure washer is the K7.3 best suited for? The K7.3 unloader operates at 6.6 to 10.8 GPM and supports a maximum pressure of 3500 PSI. It pairs well with popular 5.5–8 GPM commercial pumps. Very small homeowner units or extremely high-pressure, low-flow machines need a different type of unloader.

• Is the K7.3 suitable for hot water pressure washers? Yes. With a maximum operating temperature of approximately 165°F, the K7.3 is commonly used on hot water units for fleet washing, grease removal, and sanitation work. It is not designed for steam applications.

• How often should I service or inspect the unloader? A practical starting point is to inspect the K7.3 every 200–300 operating hours or at least once per season. In harsh or high-use environments-dusty job sites, daily commercial work-check more frequently for wear, leaks, and debris buildup.

• What causes low pressure even with the K7.3 installed? Low pressure can come from worn nozzle orifices, pump wear, air leaks at the inlet, clogged water filters, or a misadjusted unloader. It reduces pressure spikes to prevent damage in the plumbing system, but it can't compensate for upstream or downstream issues. Diagnose the full system, not just the unloader.

Ready to Optimize Your Pressure Washer Setup?

• The General Pump K7.3 unloader delivers the consistency, comfort, and pump protection that professional machines demand-smoother trigger response, reliable bypass, and steady system pressure across long hose runs and tough jobs.