Collection: Shop Triplex Pressure Washer Replacement Pumps

Why choose a triplex pressure washer pump?

Triplex plunger pumps are the workhorses of professional pressure washing. Compared to consumer-grade axial (wobble) pumps, a triplex pump:

• Lasts 5–10× longer — three ceramic plungers share the load, running cooler and with far less wear.
• Delivers higher pressure — 2,500 to 5,000+ PSI with rock-steady flow, no pulsing.
• Is fully rebuildable — seals, plungers, valves, and manifolds can be serviced individually instead of replacing the whole pump.
• Runs continuously — rated for commercial duty cycles instead of the 15–30 minute limits on entry-level pumps.
• Handles higher inlet temps — up to 140 °F on most models, ideal for hot-water and detergent applications.

If your current pump is losing pressure, leaking oil, cavitating, or hard to prime, upgrading to a matched triplex replacement almost always restores original performance instead of forcing a whole-machine buy.

How to choose the right triplex replacement pump

Five specs decide whether a pump will bolt on and run correctly. Match all five and you're done.

1. Mount type & shaft size — the single most important fitment spec. Common configurations:
   • Hollow shaft (3/4" or 1") — slips over the engine's crankshaft (Honda GX, Kohler, Briggs, Predator).
   • Solid shaft (3/4" SD, 1" SD, 24mm, 18mm) — couples to an electric motor or belt/pulley drive.
   • Gearbox / gear-reduction mount — used when the pump RPM must differ from the engine RPM (larger 5–13 GPM units).
2. PSI rating — match or slightly exceed your machine's original spec. Under-specing costs cleaning power; over-specing wears fittings and hoses. Common bands: 2,000–2,700 PSI (light‑duty electric), 2,800–3,600 PSI (residential/prosumer), 3,700–4,500 PSI (commercial), 4,500+ PSI (industrial).
3. GPM (gallons per minute) — determines rinse speed and heat recovery. Never exceed the engine/motor's rated horsepower for the pump's PSI×GPM combo (rule of thumb: engine HP ≥ PSI × GPM ÷ 1,460).
4. Drive type — direct drive (pump bolts to engine/motor, runs at motor RPM — typically 3,400 RPM) or belt drive (pulley-reduced to ~1,450 RPM for longer service life and cooler running). Belt-drive pumps generally outlast direct-drive by 3×.
5. Rotation direction & port location — a few pumps are handed; verify inlet/outlet port location matches your plumbing before ordering.

Not sure which pump fits your washer? Call us at (888) 714‑1410 with your machine's make, model, and serial number and we'll match the right pump for you.

Shop triplex pumps by category

By horsepower / engine size: 2 HP · 7.5 HP+

By brand: Annovi Reverberi (AR) · Mi-T-M · Comet · Simpson

Related: Complete Pressure Washers · Pressure Washer Accessories · Pressure Washer Pump Types & Features (guide)

Frequently asked questions

How do I know what triplex pump fits my pressure washer?
Check five specs on your existing pump's data plate or in your owner's manual: mount type (hollow/solid shaft), shaft diameter (3/4", 1", 24mm, etc.), PSI rating, GPM, and drive type (direct or belt). Match all five and the replacement will bolt on. If you can't find the info, take a photo of the old pump and send it to us — we'll identify it.

Can I upgrade my pressure washer to a higher-PSI triplex pump?
Sometimes — but only if your engine or motor has the horsepower to drive it. The formula is HP ≥ (target PSI × GPM) ÷ 1,460. Undersized engines will bog down, overheat, and shorten the pump's life. If you're unsure, call us before ordering.

Are AR (Annovi Reverberi) triplex pumps as good as Cat or General Pump?
Yes — AR is one of the three largest triplex pump makers in the world and is the OEM pump on many Simpson, Northstar, and Pressure Pro washers. The internals (ceramic plungers, stainless valves, brass manifold) are equivalent to Cat and General across most models. Choose based on the pump kit that matches your original spec.

What's the difference between a triplex pump and an axial pump?
An axial (wobble) pump uses a swash-plate to drive three pistons off a single wobble bearing — simpler and cheaper, but the whole plate wears together and can't be rebuilt. A triplex pump uses three separate connecting rods and crankshaft-driven plungers, so each cylinder wears independently, runs cooler, holds pressure more precisely, and can be rebuilt many times.

How long should a triplex pump last?
With clean water, regular oil changes (typically every 200–300 hours), and unloader/thermal-relief protection, a quality triplex pump commonly runs 1,500–3,000+ hours between rebuilds. Belt-drive setups typically outlast direct-drive by 2–3× because they run at lower RPM.