ALLPARTS BASIC Chemical Injector Kit 7104228 — OEM-style replacement for Simpson pumps, stainless ball & O-ring

The ALLPARTS BASIC 7104228 Chemical Injector Kit is a direct OEM-style replacement injector assembly for many Simpson, AAA and compatible pressure washer pumps.

This compact repair kit restores the soap/chemical pickup function on a wide range of portable cold- and hot-water pressure washer pumps. Designed to match the original equipment thread and internal parts, the kit includes the barbed nipple with O-ring, stainless steel ball, and spring you need to replace a worn or damaged injector quickly. It fits dozens of common pump models used by Simpson, Delco, DeWalt, Stanley, AAA, OEM Technologies and several others, and it is built for straightforward installation without modifying your pump.

Which pumps will this injector kit work with?

The 7104228 kit is compatible with a large list of 5100-, 5200-, and 5300-series pumps and all BRD and ALD series units from AAA. Confirm your pump model against the list in your owner’s manual to ensure a correct match before buying.

• Fits models: 510001, 510003, 510011, 510014, 510015, 510020
• Also fits: 520001, 520002, 520004, 520006
• Included 5300-series coverage: 530001, 530008, 530009, 530010, 530011, 530016, 530017
• Covers AAA BRD & ALD series pumps and many OEM-compatible portable washers

How do I install the 7104228 chemical injector kit?

Installation is typically quick for someone comfortable with basic pump maintenance. Remove the old injector components, seat the new stainless ball and spring, then thread the barbed nipple in with its O-ring to seal the pickup port. Use only moderate torque—overtightening can damage threads.

• Hand-tighten, then snug with a wrench if needed
• Verify the 0.90 mm (1/8"-28 BSPP/G) thread pitch before starting
• Replace O-ring if damaged to prevent leaks
• If the old injector breaks, an EZ-out extractor may be required

What parts are included and why they matter?

The kit contains the three wear items that control chemical pickup: a barbed nipple with O-ring to connect supply tubing, a corrosion-resistant stainless steel check ball, and a return spring. Replacing those together restores the injector’s sealing and one-way flow performance without hunting for individual components.

• Barbed nipple with O-ring: secures tubing and prevents leaks
• Stainless steel ball: resists corrosion, ensures reliable check action
• Spring: provides correct seating pressure for the ball
• Packaged and tested to match OEM fit and function

What if the injector breaks off in the pump body?

If an injector fragment remains lodged in the pump, normal removal may fail and additional tools are needed. An EZ-out or similar extractor can remove broken threaded pieces; these tools are commonly available at hardware stores and help avoid replacing the entire pump housing.

• EZ-out extractors remove stuck threaded parts
• Work carefully to avoid scoring the pump housing
• When in doubt, seek professional service to prevent further damage
• Replacing the injector kit alone won’t fix a fused or broken-in-place threaded insert

Who is this for? The ALLPARTS BASIC 7104228 kit is aimed at homeowners, contractors and service technicians who maintain Simpson and OEM-equivalent portable pressure washers and need a reliable, OEM-spec chemical injector replacement. It’s ideal when the original injector is worn, leaking, or missing—providing the three critical components necessary to reestablish safe, controllable chemical pickup without replacing the entire pump assembly. Verify compatibility with your pump model before purchase to ensure a smooth, trouble-free repair.