---
product_id: 248721937
title: "AAA 90034 Horizontal Triplex Plunger Replacement Pressure Washer Pump Kit, 4400 PSI, 4.0 GPM, 1\" Shaft, Includes Hardware and Siphon Tube, for Industrial Gas Powered Machines, Black"
brand: "simpson"
price: "€ 86.92"
currency: EUR
in_stock: false
url: https://www.desertcart.ie/products/248721937-aaa-90034-horizontal-triplex-plunger-replacement-pressure-washer-pump-kit
store_origin: IE
region: Ireland
---

# 4.0 GPM flow rate 4400 PSI max pressure 1" shaft with SAE bolt pattern AAA 90034 Horizontal Triplex Plunger Replacement Pressure Washer Pump Kit, 4400 PSI, 4.0 GPM, 1" Shaft, Includes Hardware and Siphon Tube, for Industrial Gas Powered Machines, Black

**Brand:** simpson
**Price:** € 86.92
**Availability:** ❌ Out of Stock

## Summary

> ⚡ Upgrade your clean game — pressure, power, precision!

## Quick Answers

- **What is this?** AAA 90034 Horizontal Triplex Plunger Replacement Pressure Washer Pump Kit, 4400 PSI, 4.0 GPM, 1" Shaft, Includes Hardware and Siphon Tube, for Industrial Gas Powered Machines, Black by simpson
- **How much does it cost?** € 86.92 with free shipping
- **Is it available?** Currently out of stock
- **Where can I buy it?** [www.desertcart.ie](https://www.desertcart.ie/products/248721937-aaa-90034-horizontal-triplex-plunger-replacement-pressure-washer-pump-kit)

## Best For

- simpson enthusiasts

## Why This Product

- Trusted simpson brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Durable Build:** Dual oversized ball bearings reduce friction for long-lasting performance
- • **Universal Fit:** SAE standard bolt pattern fits most horizontal gas pressure washers
- • **Easy Oil Monitoring:** Sight glass + advanced seal tech means no dipstick guesswork
- • **Quick Connect Ready:** Compatible with top pressure washer hoses for instant setup
- • **PowerBoost Technology:** Turbocharge your clean with adjustable high-pressure control

## Overview

The AAA 90034 Horizontal Triplex Plunger Pump Kit delivers industrial-grade 4400 PSI pressure and 4.0 GPM flow for powerful cleaning. Designed for gas-powered washers with a 1" shaft and horizontal engine, it features PowerBoost adjustable pressure, easy oil level monitoring via sight glass, and durable dual ball bearings. Compatible with standard SAE bolt patterns and quick-connect hoses, this kit extends your pressure washer’s life with effortless installation and reliable performance.

## Description

Engineered to surpass expectations, the 90034 AAA Professional Triplex Pump is highly efficient and minimizes engine load while delivering top performance. This easy-to-install pump replacement kit is for gas pressure washers* with a horizontal engine and a 1" diameter shaft, such as the Honda GX390. This pump can produce up to 4400 PSI at 4.0 GPM. The 90034 is designed with dual oversized ball bearings to reduce friction and allow for long lasting performance in the toughest cleaning environments. The 90034 features a stainless steel integrated unloader featuring our easy-start system. (*Check your pressure washer's inlet and outlet orientation to ensure compatibility)

## Features

- Extend the life of your pressure washer: Save money by replacing your pump instead of buying a whole new power washer. This easy-to-install kit is great for power washers that can support 4400 PSI at 4.0 GPM to wash walls, sidewalks, vehicles, and more
- Compatibility: SAE standard bolt pattern fits many gas pressure washers with horizontal engines. To ensure compatibility, be sure to match engine orientation, PSI, GPM, engine shaft diameter, and current pump inlet and outlet connection
- Adjustable power: Pump includes PowerBoost Technology that delivers higher pressure at the nozzle for a more efficient cleaning experience; There is also a hand turn knob that lets you reduce power at your convenience for tasks that require lower pressure
- Know when to change your oil: The sight glass and advanced oil seal technology eliminates the need for a dipstick. With visibility to the oil level and the oil itself, you can easily see when oil levels are low or if water has clouded the oil
- Standard Connections: This replacement pump features a garden hose inlet and quick connect high pressure hose outlet; Use it with many pressure washer hoses, including Simpson Armor 41114, 41096, 41115 or Simpson Monster 41113, 41028, 41030, 41032, 41034

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Manufacturer | simpson |
| Part Number | 90034 |
| Product Dimensions | 29.21 x 29.21 x 27.94 cm; 7.26 kg |
| Item model number | 90034 |
| Colour | Black |
| Style | 4400 PSI at 4.0 GPM |
| Material | Brass |
| Power Source | Gas Powered |
| Voltage | 120 |
| Item Package Quantity | 1 |
| Flow rate | 4 Gallons Per Minute |
| Measurement System | US |
| Included Components | Pump Kit |
| Batteries included? | No |
| Batteries Required? | No |
| Item Weight | 7.26 kg |

## Product Details

- **Brand:** SIMPSON
- **Colour:** Black
- **Material:** Brass
- **Style:** 4400 PSI at 4.0 GPM
- **Product dimensions:** 29.2L x 29.2W x 27.9H centimetres
- **Power source:** Gas Powered
- **Item weight:** 16 Pounds
- **Maximum flow rate:** 4 Gallons Per Minute
- **Voltage:** 120
- **Global Trade Identification Number:** 00879399002335

## Images

![AAA 90034 Horizontal Triplex Plunger Replacement Pressure Washer Pump Kit, 4400 PSI, 4.0 GPM, 1" Shaft, Includes Hardware and Siphon Tube, for Industrial Gas Powered Machines, Black - Image 1](https://m.media-amazon.com/images/I/71UfvYTtB6L.jpg)
![AAA 90034 Horizontal Triplex Plunger Replacement Pressure Washer Pump Kit, 4400 PSI, 4.0 GPM, 1" Shaft, Includes Hardware and Siphon Tube, for Industrial Gas Powered Machines, Black - Image 2](https://m.media-amazon.com/images/I/81rCGPKmcTL.jpg)
![AAA 90034 Horizontal Triplex Plunger Replacement Pressure Washer Pump Kit, 4400 PSI, 4.0 GPM, 1" Shaft, Includes Hardware and Siphon Tube, for Industrial Gas Powered Machines, Black - Image 3](https://m.media-amazon.com/images/I/81Zf+oKnljL.jpg)
![AAA 90034 Horizontal Triplex Plunger Replacement Pressure Washer Pump Kit, 4400 PSI, 4.0 GPM, 1" Shaft, Includes Hardware and Siphon Tube, for Industrial Gas Powered Machines, Black - Image 4](https://m.media-amazon.com/images/I/81G0Sx-EA5L.jpg)
![AAA 90034 Horizontal Triplex Plunger Replacement Pressure Washer Pump Kit, 4400 PSI, 4.0 GPM, 1" Shaft, Includes Hardware and Siphon Tube, for Industrial Gas Powered Machines, Black - Image 5](https://m.media-amazon.com/images/I/81xGC9O7ZVL.jpg)

## Questions & Answers

**Q: Que medida es el eje o el chaf**
A: 1 inch

**Q: I have a 13 hp Honda with 4000 psi 3.8gpm cat pump...will this pump mount with same bolt pattern?**
A: ABSOLUTELY, no problem. Perfect fit for the GX390, WELL WITHIN SPECS! Better pump choice is the AR RKV45G40HD-F24 4000psi @ 4.5 gpm OR Bertolini WMG 4043 4000psi @ 4.3 gpm ......both superior to the "tipple A" ....Although the "cat" is better quality than all the above in the 4000 @ 4.0 gpm, but pricey! Keep in mind, that when a "pressure washer manufacture" like DeWalt publish a given pressure, it's typically 8% above the actual pressure EVER achievable. The reason for this is a deceiving sales tactic that manufactures like DeWalt take advantage of. The ASTM guidelines on pressure washers allow for a 8%  in min/max operating pressures so the pressure washer manufacture (not the pump mfg) takes the MAX pressure the actual pump is capable of producing and multiply by .08 and round down to the next "whole number". The cat pump on you're machine is only capable in the neighborhood of 3800 psi. ANY of the above listed pumps will exceed the performance of your OEM equipment from De Fault!

**Q: Will this pull water from a tank?**
A: i use a water tank it' in a truck so it's higher than the pump gravity feed

**Q: Will this fit dxpw4035 dewalt pressure washer?**
A: Technically it would fit on the Honda Engine but this pump required a 13HO GX390 Engine and the DXPW4035 has a GX270 9HP engine.

The suggested replacement pump is the 90038 AAA Pump

Thank You

Allparts Equipment Technical Service Team

## Frequently Bought Together

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*Product available on Desertcart Ireland*
*Store origin: IE*
*Last updated: 2026-03-16*