The Fortpro Single Cylinder Air Brake Compressor is engineered as a high-performance replacement for OEM part 9121120020, servicing Mack MP8 engines and Volvo FH12, FM12, NH12, and FM9 series heavy-duty trucks. Featuring an 85 mm piston diameter, 56 mm stroke, 318 cm³ swept volume, and M20 x 1.5 crankshaft thread, this water-cooled engine-driven compressor operates up to 203.1 psi at 3000 RPM, delivering maximum air pressure and system reliability for commercial air brake systems.
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Basic Part Information6 attributes
| Product Line | Brakes |
|---|---|
| Category Name | Air Brake Compressors |
| Part Type | Air Brake Compressor |
| Alternate Part Name | Brake System Air Compressor, Heavy-Duty Air Compressor, Engine-Driven Air Compressor, Truck Air Compressor |
| OEM Part Number | 9121120020 |
| Condition | New |
Application/Fitment Attributes9 attributes
| Application Type | Heavy Duty Trucks, Semi-Trucks |
|---|---|
| Crankshaft Thread Specification | M20 x 1.5 |
| Mounting Type | Flange Mount |
| Port Thread 0 | Ø 34.9 mm |
| Port Thread 2 | M26 x 1.5 |
| Port Thread 4 | M16 x 1.5 |
| Port Thread 8.1 | M12 x 1.5 |
| Port Thread 9.1 | M16 x 1.5 |
| Port Thread 9.2 | M16 x 1.5 |
Dimensional/Physical Attributes4 attributes
| Calculated Volume | 15.84 dm³ |
|---|---|
| Piston Diameter | 85 mm |
| Piston Stroke | 56 mm |
| Swept Volume | 318 cm³ |
Technical/Performance Attributes5 attributes
| Cooling Method | Water |
|---|---|
| Cylinder Quantity | 1 |
| Lubrication Type | Lubrication supplied from engine |
| Maximum Operating Pressure | 203.1 psi |
| Operating Speed | 3000 (1/min) |
Intended Application
- Compatible with Mack MP8 Engines with Single Cylinder Air Compressor.
- Compatible with Volvo FH12 FM12 NH12 FM9 Trucks.
- Always compare with your OEM part number prior to purchase to confirm full compatibility.
- Mack: 20451727, 21353433
- Wabco: 9121120020, 9121120000, 9121120007