Dorman 902-5403CD Engine Coolant Reservoir Cap

Engine Coolant Reservoir Cap Replacement

Restore a secure seal on the cooling system with this Dorman engine coolant reservoir cap, part number 902-5403CD. It is a direct replacement for a cracked or missing coolant tank cap and is built with a 49 mm twist-on design for a straightforward service replacement.

For drivers searching for an engine coolant reservoir cap for Honda Civic or Toyota Corolla cooling system service, 902-5403CD provides a simple OE-style solution. The black plastic construction and non-pressurized design make it a practical choice for reservoir cap replacement on the correct application.

Key Features

• Direct replacement engine coolant reservoir cap from Dorman
• Part number 902-5403CD for catalog and fitment reference
• 49 mm diameter with twist-on attachment type
• Black plastic construction
• Non-pressurized, non-vented design
• Compact reservoir cap profile for a clean OE-style fit

Detailed Product Information

Dorman 902-5403CD is engineered as a replacement coolant tank cap for vehicles that use a 49 mm twist-style reservoir opening. If the original cap is cracked, lost, or no longer sealing properly, this cap restores the reservoir closure needed for normal cooling system operation. The design focuses on direct fitment and simple service replacement rather than modification or adaptation.

This part cross-references CALORSTAT by Vernet RC0050 for the same application. When replacing a coolant reservoir cap on Honda Civic or Toyota Corolla cooling systems, confirm the cap style and diameter match the original component before installation.

What This Part Helps Solve

• Cracked coolant reservoir cap
• Missing engine coolant tank cap
• Loose or damaged twist-on reservoir closure
• Improper sealing at the coolant expansion tank opening
• Service replacement for a worn plastic cap

Installation Notes and Tips

Verify the reservoir opening measures 49 mm and uses a twist-on cap before installation. Inspect the tank neck and sealing surface for damage, debris, or distortion, then install the cap by hand until it seats fully. For Honda Civic and Toyota Corolla applications, compare the original cap style to Dorman 902-5403CD to confirm the correct replacement.

Quality Assurance

This Dorman coolant reservoir cap is built as a direct replacement part for the specified application and is intended to match the original cap style and dimensions. Part number 902-5403CD is designed for straightforward service replacement when the original reservoir cap is no longer usable.