Dorman 603-830 Engine Coolant Reservoir - Front

Overview of Dorman Engine Coolant Reservoir 603-830

The Dorman 603-830 engine coolant reservoir is designed for select BMW models, providing reliable coolant storage and pressure management. This reservoir features a durable plastic construction and includes a spring loaded twist cap with a 20 psi pressure rating to maintain optimal engine cooling system performance.

• Constructed from durable black plastic for corrosion resistance
• Dimensions: 7.5 inches length, 11.5 inches height with an irregular shape
• Includes a spring loaded twist cap rated for 20 psi maximum pressure
• Equipped with a level sensor for accurate coolant monitoring
• Cap and level sensor included for complete functionality
• Six mounting holes for secure installation (mounting hardware not included)
• Capacity of 1.5 liters to meet cooling system requirements

Detailed Product Description

The Dorman 603-830 engine coolant reservoir is engineered to meet the specifications of various BMW vehicles, including the 530i, 535d, 640i, 740Li, and ActiveHybrid series. Its black plastic construction offers resistance to heat and corrosion, ensuring long-term durability. The irregular shape is designed to fit precisely within the engine bay of compatible BMW models. The included spring loaded twist cap maintains system pressure up to 20 psi, which is critical for preventing coolant loss and overheating. Additionally, the integrated level sensor provides real-time coolant level monitoring, helping to avoid engine damage due to low coolant levels.

Compatible BMW Models and Applications

• BMW 530i, 535d, 535d xDrive, 535i, 535i GT, 535i GT xDrive, 535i xDrive
• BMW 640i, 640i Gran Coupe, 640i xDrive, 640i xDrive Gran Coupe, 640i xDrive Gran Turismo
• BMW 740i, 740Ld xDrive, 740Li, 740Li xDrive
• BMW ActiveHybrid 5 and ActiveHybrid 7

Common Issues Addressed by This Coolant Reservoir

• Coolant leaks due to cracked or damaged reservoir tanks
• Inaccurate coolant level readings from faulty or missing sensors
• Loss of system pressure causing engine overheating
• Degraded or missing reservoir caps leading to coolant evaporation
• Improper fitment causing coolant system malfunctions

Installation Notes and Tips

When installing the Dorman 603-830 engine coolant reservoir, ensure the six mounting holes align correctly with the vehicle’s mounting points. Note that mounting hardware is not included and must be sourced separately. Carefully connect the level sensor wiring to the vehicle’s electrical system to maintain accurate coolant level readings. Verify the spring loaded twist cap is securely tightened to maintain the 20 psi pressure rating. Always inspect the cooling system for leaks after installation and refill coolant to the recommended level.

Quality Assurance and Warranty

Dorman parts are manufactured to meet or exceed OEM standards for fit, form, and function. The 603-830 engine coolant reservoir undergoes rigorous quality control to ensure durability and performance in demanding automotive environments. Please refer to Dorman’s warranty policy for specific coverage details.