Centurion P8 Belt Drive Triplex 4000PSI 4.0GPM Pressure Washer Pump - 85.129.106B

Heavy duty precision, quiet operation and a ton of power - the kind of pump that pros who work long hours need.

Built for the Job

The Centurion P8 Belt Drive Triplex Pump (85.129.106B) is what you want when you're doing heavy-duty jobs that require a pump that's going to keep going all day long. Built by CP, a top company in pump engineering, this thing delivers a serious 4,000 PSI of water pressure at 4.0 GPM without getting loud or overheating. And whether you're running a gas or electric motor, its 24 mm shaft, 1,450 RPM operation, and nickel-plated brass manifold make it a rock solid pump.

It's especially great for contractors, car washes and heavy industrial cleaning - anyone who's running their pump for hours at a time. The belt drive configuration reduces wear and tear and keeps it running smoothly for a long time. This pump's built for pros who don't just clean - they get the job done.

Technical Overview

• Part Number: 85.129.106B

• Bare Pump Part Number: 85.120.106B

• Pump Manufacturer: CP

• Pump Model: CTB1S

• Drive Type: Belt Drive (Gas / Electric Compatible)

• Shaft Size: 24 mm

• Pump Style: Triplex

• Max PSI: 4,000

• Max GPM: 4.0

• Unloader Type: External

• Plunger (Piston): Ceramic

• Inlet Size: 3/4" GHF

• Discharge Size: 3/8" Brass QC

• Soap Injector: Adjustable

• Manifold Type: Nickel-Plated Brass

• RPM: 1,450 - a nice, steady speed

• Max Inlet Temp: 60°C / 140°F

• Thermal Relief Valve: 85.300.024

• Oil Capacity: 32 fl oz

• Oil Type: 30W Non-Detergent

• Weight: 27.5 lbs

• Warranty: 7 Years

Designed to Keep Going

The Centurion P8 does more than just deliver massive power - it's built to run cool, quiet and all day long without breaking a sweat. The belt drive system keeps the pump decoupled from the engine or motor, cutting down on vibration and letting it run at a nice 1,450 RPM. Less vibration and less heat buildup mean less maintenance down the line.

It's perfect for:

• Big commercial cleaning ops

• Fleets and equipment washing

• Ag and food processing facilities

• Construction and concrete cleaning

• Manufacturing and facility maintenance

• Car washes and mobile detailing systems

This pump's built to take a beating and keep going - day in and day out.

What You Get

Triplex Ceramic Plunger System

The P8 has a triplex plunger design that makes sure you get a smooth, steady water flow. The plungers are made from ceramic, which is great at resisting corrosion and wear - it means your seals and valves will last longer.

Nickel-Plated Brass Manifold

Unlike regular brass or aluminum manifolds, the nickel-plated brass manifold is super resistant to corrosion - even when you're using detergents or slightly caustic solutions. It's durable and precise - perfect for the job.

External Unloader System

The external unloader lets you adjust water pressure and bypass flow - so you can fine tune the pump for any job. And when it's time to service or replace it, the external design makes it a piece of cake.

Adjustable Soap Injector

The built-in adjustable soap injector lets you fine tune your detergent application - perfect for cleaning cars, buildings or heavy machinery. Switch between high-pressure rinse and soap easily.

Thermal Relief Valve Protection

The P8's got thermal relief valve protection - so you don't have to worry about overheating. To protect internal seals from heat damage.

The P8 comes equipped with a thermal relief valve (85.300.024) that instantly kicks in to release overheated water when the system goes into bypass mode. This clever system self-regulates water temperatures to keep them safely within operating limits - even during prolonged periods of inactivity.

Giving you Long Service Intervals

That's thanks to an impressive 32 fl oz oil capacity in the P8's oil-bath crankcase. This ensures continuous lubrication and efficient cooling, with 30W non-detergent oil providing clean, consistent lubrication that doesn't foam. This all adds up to oil changes that are significantly less frequent and maintenance intervals that are a whole lot longer.

Smoother, Quieter, Low-RPM Operation

One of the big advantages of the P8's belt drive system is its ability to run smoothly at just 1,450 RPM. As opposed to those direct drive pumps that spin at over double that speed, this low RPM design means the P8 is:

• Easier on bearings, seals and plungers - reducing wear and tear.

• Cooler running, even after long periods of hard work.

• Less prone to vibration - which reduces stress on the engine or frame.

• Quieter still, making it perfect for indoor or urban cleaning jobs.

All this together means the P8 performs well out of the box and goes on to perform consistently over the years - making it one of the lowest maintenance costs in its class.

Precision Craftsmanship & High-Grade Materials

Every Centurion pump is the result of meticulous engineering and decades of pump manufacturing expertise. The P8 (CTB1S) model takes this expertise to the next level:

• The crankshaft is precision-machined for perfectly balanced rotation.

• The connecting rods are hardened for long-term durability.

• The seals and valves are high quality and made from heat resistant materials.

• The manifold is nickel plated brass for extra corrosion protection.

• The plungers are ceramic and designed to withstand high temperatures and abrasion.

All these features come together to give the P8 years of consistent, professional-grade performance - with minimal downtime and low maintenance costs.

Built to Work with Belt Drive Power Systems

The Centurion P8's 24 mm solid shaft is compatible with a wide range of pulleys and couplers for belt-driven configurations. This gives you the flexibility to use it with gas engines or electric motors - making it perfect for mobile pressure washer trailers or stationary industrial cleaning systems.

Benefits of Using a Belt Drive Configuration:

• It isolates engine and pump vibration - reducing stress on both.

• It reduces heat buildup - extending seal and bearing life.

• It allows for lower pump RPM - extending service intervals.

• It makes alignment adjustments and serviceability a breeze.

Whether you're running a high-torque electric motor or a 13-20 HP gas engine, the P8 delivers smooth, consistent performance under continuous operation.

Where it's Used

The Centurion P8 is built for professionals who demand performance, reliability and durability. Its 4,000 PSI and 4.0 GPM output makes it suitable for a wide range of demanding cleaning applications across various industries:

• Fleet Washing: it efficiently removes dirt, oil and grime from trucks and trailers.

• Agricultural Cleaning: keeps tractors and heavy machinery running cleanly.

• Industrial and Manufacturing: perfect for cleaning machinery and equipment.

• Property Maintenance: it handles concrete, brick, siding and walkway cleaning with ease.

• Construction Sites: removes cement, paint and debris from tools and surfaces.

• Car Wash Systems: operates quietly and efficiently for self-serve and automatic bays.

Its durability and low-RPM design make it a workhorse that can run daily without failure - making it one of the most trusted belt drive pumps on the market.

Easy Maintenance & Servicing

While the P8 is engineered for long service life, easy maintenance is at the core of its design. This makes it easy to perform fast, straightforward service when needed:

• Check the oil level before each use and replace it after the first 50 hours, then every 500 hours or quarterly.

• Inspect the drive belts for proper tension and wear.

• Make sure the thermal relief valve is working properly to prevent overheating.

• Replace seals and valves at regular intervals depending on operating hours and water quality.

• Flush the adjustable soap injector after each use to prevent clogging.

These simple steps will keep your pump running at peak performance - extending its lifespan far beyond standard commercial expectations.

Performance that Endures

The Centurion P8 represents the perfect balance of power, precision and endurance that professionals demand. Its low-RPM belt drive design offers extended run time and efficiency, while the triplex ceramic plunger system guarantees steady and reliable water flow.When put up against direct drive systems, belt drive pumps like the P8 regularly outlast them by 2–3 times, making them a go-to choice for daily-use equipment and stationary systems.

The Lowdown on the P8:

• 4,000 PSI of pressure - plenty of grunt for heavy-duty cleaning jobs.

• 4.0 GPM flow - steady, reliable performance from this pump.

• Belt drive design reduces RPM, noise and wear and tear on the pump.

• A nickel-plated brass manifold keeps corrosion at bay.

• Adjustable unloader and soap injector give you the precision control you need.

• Thermal relief protection looks after the seals - and they'll last a lot longer because of it.

• And to top it all off, there's a 7-year warranty that's backed by CP's engineering know-how.

Getting the P8 Up and Running

For pros, installing the Centurion P8 is a relatively straightforward process. This is a belt drive pump and it can be set up with a variety of pulley ratios to get the perfect balance of flow and pressure for both gas and electric motors.

Here's what you need to do:

1. Mount the pump to a solid base or frame.

2. Line the 24 mm shaft up with the pulley and tighten securely.

3. Get the belt tension just right - not too loose, but not too tight either.

4. Connect the 3/4" GHF inlet and 3/8" QC discharge fittings.

5. Fill with 32 fl oz of 30W non-detergent oil.

6. Test for pressure stability and unloader adjustment before you start using the pump.

The fact that this pump is so easy to install and set up makes it perfect for OEMs, service pros and system integrators looking for a reliable pump for custom builds or replacements.

You can trust the P8 - it's got a 7-Year Warranty

Like all Centurion pumps, the P8 is backed by a 7-year manufacturer’s warranty that demonstrates CP's commitment to building quality, reliable pumps. Every pump is put through its paces - pressure-tested, flow-tested, and inspected for precision - before it even leaves the factory.

This isn't just a promise - it's proof that CP builds pumps that are designed to last. The P8 will keep delivering power and performance long after other pumps have given up the ghost.

What you need to know about the P8

• Model: CTB1S (Centurion P8) - that's the model number you'll need.

• PMR Part #: 85.129.106B - this is the part number for the P8.

• Drive Type: It's a belt drive pump - and it works with both gas and electric motors.

• Pump Style: It's a triplex ceramic plunger pump.

• Pressure / Flow: The P8 can produce 4,000 PSI at 4.0 GPM.

• RPM: It runs at a low 1,450 RPM.

• Manifold: The manifold is made from nickel-plated brass.

• Unloader: The unloader is external and adjustable.

• Soap Injector: It's also adjustable.

• Thermal Relief Valve: You get a thermal relief valve to protect the seals.

• Oil Capacity: The oil capacity is 32 fl oz of 30W non-detergent oil.

• Weight: The P8 weighs in at 27.5 lbs.

• Warranty: And to top it all off, there's a 7-Year Warranty.

The Centurion P8 Belt Drive Triplex 4000 PSI 4.0 GPM Pressure Washer Pump (85.129.106B) gives you industrial-grade cleaning power with a level of smoothness and durability that you just can't get from other pumps. The nickel-plated brass manifold, ceramic plungers and low-RPM belt drive system all come together to make this the ultimate long-life pump solution for high-output gas or electric pressure washers.

It's quiet, it's efficient, and it's backed by a 7-year warranty - and all that adds up to the P8 being the ultimate powerhouse of precision and endurance - built to keep your operation running smoothly for years to come.

The Centurion P8 - it's the real deal.