[BigHeadClan]

It you aren't totally replacing the fluid their would be a section under the owners manual, but provided you didn't loose that much coolant swapping the out the plastic piece you can simply add the missing coolant back via the coolant revivor. Just make sure you are using 50/50 premix coolant that is designed for aluminum engines and or specifically says designed for Nissan/Infiniti engines.

FSM can be found below if you need more details.

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