AR 42118 Unloader Repair Kit RMV/RMW/SRMW - 1944

Restore Safe, Reliable Pressure to Your AR RMV & RMW Pumps in One Simple Rebuild

The AR North America 42118 unloader repair kit is a complete rebuild solution for AR RMV, RMW, and SRMW series pressure washer pumps rated between 2,500 and 3,000 PSI. If your unit has lost pressure, pulses erratically, or refuses to come out of bypass, this kit delivers every internal component you need to restore proper unloader valve function without replacing the entire pump.

The main benefit is straightforward: safe, stable pressure regulation returns to your machine. Pressure washer unloader valves manage and regulate water flow and pressure, and when they wear out, the results range from annoying pressure drops to genuine damage from overpressure. This kit eliminates those risks and gets your washer back to spec quickly.

The AR42118 unloader kit replaces models 202328GS, 315747GS, and 200348GS, covering a wide range of residential and light commercial units built around AR's proven cartridge-style unloader design. Rather than hunting for individual parts or gambling on generic seals, you get the full rebuild in a single package.

Why You'll Love the AR North America 42118 Unloader Repair Kit

Here's what this kit means in practical terms for homeowners, DIYers, and light-duty contractors running AR RMV or RMW pumps:

• Restore full pressure and a consistent spray pattern – A worn pump unloader causes weak output, pulsing, and erratic spray. Fresh internal components bring your pressure washer pump back to its rated PSI and GPM, so cleaning jobs finish faster and more evenly.

• Extend the life of your existing pump – Unloader valves are essential to prevent damage from overpressure in pressure washers. A rebuilt unloader keeps heat and excess pressure from reaching pistons, seals, and the manifold-avoiding early pump failure that would cost far more to fix.

• Prevent pressure spikes and engine stalling – When you release the trigger gun, a functioning unloader redirects water into bypass smoothly. Without it, the engine bogs, stalls, or surges. This kit restores that deadhead protection so operation stays stable.

• Reduce leaks and downtime – New O-rings and seats stop water from weeping around the unloader body, a common error symptom that signals internal seal wear. Less leaking means less wasted water and fewer interruptions.

• DIY-friendly repair – The kit is compact, organized, and designed to be installed with basic hand tools in under an hour. No special equipment, no dealer visit-just a clean workspace and a bit of care.

What Makes This 42118 Unloader Kit Different

Many generic unloader parts sold as replacements don't match AR's tolerances or materials. The result is short service life, bypass leaks, or pressure that never quite reaches spec. The AR North America 42118 kit is a different choice.

• Engineered specifically for AR RMV & RMW series pumps – The AR42118 unloader valve is compatible with multiple models, including RMV2.5G30D, RMW2.5G27, RMW2.5G25, and select SRMW units. Bore sizes, spring rates, and seat dimensions are matched to the original casting, so fitment guesswork doesn't apply.

• OEM-spec sealing components – Springs, piston, seat, and chemical-resistant rubber O-rings are manufactured to original AR specifications. That means correct bypass behavior and pressure regulation right out of the box, with no added risk of premature failure.

• Designed for modern detergents and household water conditions – Seal materials resist common cleaning chemicals, hard water minerals, and the intermittent use patterns typical of residential machines. Regular cleaning can prevent mineral scale and hard water deposits in the pump manifold, and durable seals help ensure the unloader doesn't stick or corrode between uses.

Unlike replacing the whole pump, a targeted unloader rebuild keeps your original casting and plumbing layout intact-saving time, money, and the hassle of re-routing hoses and fittings.

How It Works

The unloader valve redirects water into bypass when the trigger gun is released and controls working pressure when you're spraying. Here's how the rebuild process works:

1. Remove the old unloader assembly Depressurize the system by shutting off the engine and pulling the trigger to release trapped pressure. Disconnect the garden hose and high-pressure hose, then remove the unloader cap or plug from the pump head. Follow specific instructions for installing the unloader valve as outlined in your pump's documentation.

2. Install the new internal components from the 42118 kit Place the new spring, piston, seat, bypass jet, and O-rings in the correct order. Lightly lubricate each seal with pump-safe grease or clean oil to prevent pinching during assembly. Secure the unloader valve properly during installation-misaligned parts or dry seals can lead to leaks.

3. Reassemble, start the washer, and fine-tune pressure Reinstall the cap and retaining hardware, reconnect hoses, and start the pressure washer. Replacement unloader kits must be calibrated after installation, so adjust the unloader knob (if your model has one) until the spray pattern and engine load are stable and pressure reads within your pump's rated range.

Product Details

Quick reference for the key specs of the AR North America 42118 unloader repair kit:

• Material / Components – Hardened metal piston and seat, plated metal springs, and chemical-resistant rubber seals and O-rings. All parts are manufactured to OEM Annovi Reverberi specifications.

• Operating range – Designed for pumps rated 2,500–3,000 PSI with flow rates of approximately 2.2–2.5 GPM.

• Compatibility – AR42118 unloader kit is compatible with RMW RMV series, including RMV2.5G30D, RMV2.5G25D, RMV2.5G27D, RMW2.5G25, RMW2.5G27, RMW2.5G26D-F7, RMW2G20, RMW2G23B, RMW2G24, and select SRMW models. Verify the pump model stamped into your pump housing before you order.

• Replaces these part numbers – AR42118, 202328GS, 315747GS, 200348GS.

• Included in the package – Piston, main unloader spring, two plate springs, seat, bypass jet, piston guide, 6–8 O-rings/seals, ring, M6 nut, grub screw, and handle insert.

Frequently Asked Questions

Below are the most common questions about the AR North America 42118 unloader repair kit.

How do I know if the 42118 kit fits my pump? Check the model number stamped into your pump's cast housing (e.g., RMV2.5G30D, RMW2.5G27). Then cross-reference the old unloader part number-if it matches AR42118, 202328GS, 315747GS, or 200348GS, this kit is compatible. When in doubt, consult your pump's parts breakdown or look for a video walkthrough of your specific model.

Can I install the kit without special tools? Yes. Most installations require only basic hand tools-wrenches, a screwdriver, and a pick for removing old O-rings. A clean workspace and pump-safe lubricant are the only added requirements.

What are signs that my unloader needs to be rebuilt? Common symptoms include no pressure, inconsistent pressure, the pump staying in bypass, surging or pulsing spray, water leaking from the unloader area, or the engine lugging when you release the trigger. Any of these chapters of declining performance point to worn unloader internals.

Do I need to adjust the unloader after installation? Replacement unloader kits must be calibrated after installation. If your model has an adjustable knob, follow your pump or pressure washer manual to set pressure within safe limits. Avoid over-tightening, which can cause damage to the piston and seat.

Will this kit fix every pressure problem? While many issues are unloader-related, severely worn plungers, cracked manifolds, or clogged nozzles require additional parts or full pump replacement. If you've rebuilt the unloader and still see problems, inspect those other areas before assuming the kit is at fault.

Ready to Get Your Pressure Washer Back in Top Shape?

A failing unloader doesn't have to mean a full pump replacement. The AR North America 42118 unloader repair kit restores safe, consistent pressure and extends pump life with a targeted rebuild-replacing every wear item inside the unloader in one straightforward job.