Coolant & Washer Reservoir Cap Guide: Fitment and Safety

A coolant reservoir cap and a washer fluid cap are not interchangeable. The coolant system may be pressurized; the cap must match the neck, seal and pressure requirement. Never open a hot cooling system or replace a pressure cap with a vented or non-pressure cap.

What to check

1. OEM part number and application.
2. Reservoir neck diameter and locking tabs.
3. Pressure rating when the cap controls system pressure.
4. Seal type and condition.
5. Vent design and fluid compatibility.
6. Engine family and model year verified through a reliable parts source.

Reference MotiveCrate caps

• 21712-79900 Nissan / Infiniti coolant reservoir cap
• 96420303 Chevrolet Aveo / Pontiac G3 coolant reservoir cap
• 13227300 Chevrolet / Buick / Cadillac washer fluid cap

Browse the full Reservoir Caps collection.

Installation and safety

Let the engine cool completely before opening a pressurized cooling system. Inspect the seal and neck, fit the cap without forcing it and check for leaks after the engine reaches normal temperature.

FAQ

Can I use a washer cap on the coolant reservoir?

No. The seal and pressure behavior are different.

Does the cap pressure rating matter?

Yes. A pressure cap must match the system specification. Using the wrong cap can cause overheating or coolant loss.

Do you offer wholesale caps?

Yes. Contact service@motivecrate.com or WhatsApp for bulk orders.

Aftermarket compatibility guide. Verify the original cap number, pressure rating and application.