Monarch AOT Series Water Pumps & Repair Parts
The Monarch AOT Series of frame mount end suction centrifugal pumps is engineered for durability and versatility in pressure boosting and fluid transfer applications. Featuring a robust “All Iron” construction, these pumps are designed to be driven by either an electric motor or a gas engine through a flexible coupling, accommodating both belt drive and direct drive configurations.
Built to withstand demanding environments, the AOT Series features a thick-wall cast gray iron casing and heavy-duty components. Whether you are operating the AOT-4, AOT-5, or AOT-6 model, these pumps deliver reliable performance with an open face impeller design that resists clogging and ensures efficient operation.
Key Features and Benefits
- Rugged Construction: The casing is made of cast gray iron with a thick wall design, making it ideal for high-pressure boosting applications.
- Open Face Impeller: All AOT series pumps utilize cast gray iron impellers with an open face design for superior debris handling.
- Versatile Mounting: Frame mount design allows for flexible installation with either belt drive or direct drive systems.
- Quality Sealing: Equipped with a Buna and carbon ceramic mechanical seal for long-lasting leak protection.
- Discharge Options: Available in 1″, 1¼”, and 1½” NPT discharge sizes to fit various piping systems.
- Precision Shaft: Shaft assembly features sealed ball bearings for smooth operation and reduced maintenance.
Applications
The Monarch AOT Series is suitable for a wide range of industrial and agricultural tasks, including:
- Pressure Boosting Systems
- Water Transfer and Supply
- Agricultural Irrigation (Lawn and Sprinkler)
- Industrial Water Circulation
- Sump and Sewage Management
Technical Specifications
Performance Chart
The table below details the performance capabilities (Total Head in Feet vs. Capacities in U.S. GPM) for the AOT Series models.
| Model No. | RPM | HP | Total Head in Feet (Capacities in U.S. GPM) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 15 | 20 | 25 | 30 | 35 | 40 | 45 | 55 | 60 | 65 | 85 | |||
| AOT-4 | 3450 | 1 | – | – | – | 74 | 68 | 64 | 55 | 36 | 18 | – | – |
| 1750 | ¼ | 14 | – | – | – | – | – | – | – | – | – | – | |
| AOT-5 | 3450 | 2 | – | – | 93 | 91 | 87 | 82 | 75 | 56 | 42 | 23 | – |
| 1750 | ¼ | 24 | – | – | – | – | – | – | – | – | – | – | |
| AOT-6 | 3450 | 3 | – | – | – | 135 | 132 | 128 | 124 | 112 | 104 | 95 | 45 |
| 1750 | 1/3 | 33 | – | – | – | – | – | – | – | – | – | – | |
AOT Series Model & Transmission Data
| Model No. | Order No. | Suction NPT | Discharge NPT | Ship Wt. (lbs.) | Transmission Data |
|---|---|---|---|---|---|
| AOT-4 | 615111 | 1¼” | 1″ | 18 | Shaft Size ¾” Keyway 3/16″ Shaft assembly with sealed ball bearings |
| AOT-5 | 615121 | 1½” | 1¼” | 18 | |
| AOT-6 | 615131 | 2″ | 1½” | 21 |
Dimensions (Measured in inches)
| Model | Suct. NPT |
Disch. NPT |
DP NPT |
PP NPT |
A | B | C | D | E | F | G | H | I | J | K | L | M | N |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| AOT-4 | 1¼ | 1 | ¼ | ¼ | 7.06 | 8.38 | 3.38 | 2.40 | 1.69 | 3/16 | .75 | 3.81 | 1.30 | 8.56 | 3.75 | 4.25 | 5.63 | 7/16 |
| AOT-5 | 1½ | 1¼ | ¼ | ¼ | 7.06 | 8.38 | 2.40 | 2.19 | 1.69 | 3/16 | .75 | 3.71 | 1.30 | 8.56 | 3.75 | 4.25 | 4.63 | 7/16 |
| AOT-6 | 2 | 1½ | ¼ | ¼ | 7.75 | 8.70 | 3.75 | 2.38 | 1.88 | 3/16 | .75 | 4.19 | 1.30 | 9.31 | 3.75 | 4.25 | 5.63 | 7/16 |
Repair Parts List
Identify and order the correct replacement parts for your Monarch AOT Series pump using the table below.
| Ref.# | Code # | Pump Model No. (Modelo de la bomba) |
Qty. | Description |
|---|---|---|---|---|
| 1 | 437711 | AOT-4 | 1 | Casing |
| 1 | 437721 | AOT-5 | 1 | Casing |
| 1 | 437732 | AOT-6 | 1 | Casing |
| 2 | 438110 | AOT-4 | 1 | Impeller |
| 2 | 438120 | AOT-5 | 1 | Impeller |
| 2 | 438150 | AOT-6 | 1 | Impeller |
| 3 | 437860 | AOT-4, AOT-5, Type A | 1 | Transmission Head |
| 3 | 437861 | AOT-4, AOT-5, Type B | 1 | Transmission Head |
| 3 | 437870 | AOT-6, Type A | 1 | Transmission Head |
| 3 | 437862 | AOT-6, Type B | 1 | Transmission Head |
| 8 | 438450 | Type A | 1 | Shaft Assembly |
| 8 | 438451 | Type B | 1 | Shaft Assembly |
| 14 | 119990 | All Models | 4 | Hex. Hd. Bolt |
| 22 | 191790 | All Models | 1 | Flinger |
| *23 | 175500 | All Models | 4 | Aluminum Washer |
| 25 | 185620 | All Models | 2 | Pipe Plug |
| *26 | 193900 | AOT-4, AOT-5 | 1 | Gasket |
| *26 | 193910 | AOT-6 | 1 | Gasket |
| 28 | 432010 | All Models | 1 | Key |
| 29 | 138230 | Type A | 1 | Spring Ring |
| 29 | 137930 | Type B | 1 | Spring Ring |
| *31 | 240250 | All Models | 1 | Seal 5/8 I.D., Type 6 |
Frequently Asked Questions
What is the difference between AOT-4, AOT-5, and AOT-6 models?
What type of seal does the AOT Series use?
Can I use a gas engine with these pumps?
What are the suction and discharge port sizes?
AOT-5: 1½” Suction / 1¼” Discharge.
AOT-6: 2″ Suction / 1½” Discharge.