Honda Civic Service Manual: Radiator

Thermostat Housing Removal and Installation (R18Z1)

1141B6 1. Radiator Cap 1. Wait until the engine is cool, then carefully remove the radiator cap. ...

Radiator Connecting Pipe Removal and Installation (K24Z7)

1141E7 1. Radiator Cap 1. Wait until the engine is cool, then carefully remove the radiator cap. ...

See also:

Honda Civic Owners Manual. What to Do After the Engine Starts
Once your vehicle's engine has started, remove the jumper cables in the following order.  Disconnect the jumper cable from your vehicle's ground.  Disconnect the other end of the jumper cable from the booster battery - terminal.  Disconnect the jumper cable from your v ...