Remove the following 10 screws securing the lower case to the Air: Six 2.8 mm Phillips screws. Two 3.8 mm Phillips screws. Two 5.4 mm Phillips screws. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4617 Slightly lift the lower case near the vents and push it toward the rear of the computer to free the mounting tabs. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4618 Slightly lift the lower case near the vents and push it toward the rear of the computer to free the mounting tabs. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4618 Disconnect the battery connector by pulling it straight out of its socket. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4619 Remove the following nine screws securing the battery to the Air: Four 2.9 mm Phillips. Four 3.8 mm Phillips. One 7.2 mm Phillips. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4621 Lift the battery out of the Air. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4622 Disconnect the port hatch ribbon cable from the logic board by pulling it straight up by its black pull tab. Pull the audio out ribbon cable off the adhesive securing it to the upper case. Use a spudger to pry the audio out ribbon cable connector board off the hard drive bracket. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4652 Disconnect the port hatch ribbon cable from the logic board by pulling it straight up by its black pull tab. Pull the audio out ribbon cable off the adhesive securing it to the upper case. Use a spudger to pry the audio out ribbon cable connector board off the hard drive bracket. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4652 Disconnect the port hatch ribbon cable from the logic board by pulling it straight up by its black pull tab. Pull the audio out ribbon cable off the adhesive securing it to the upper case. Use a spudger to pry the audio out ribbon cable connector board off the hard drive bracket. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4652 Disconnect the audio out cable from its socket on the port hatch ribbon cable. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4653 Use a spudger to pry the hard drive cable connector up off the logic board. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4654 Use the sharp end of a spudger to de-route the microphone cable from the hard drive bracket. Remove the cosmetic screw cover from the adhesive securing it to the hard drive bracket. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4655 Use the sharp end of a spudger to de-route the microphone cable from the hard drive bracket. Remove the cosmetic screw cover from the adhesive securing it to the hard drive bracket. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4655 Remove the four Phillips screws securing the hard drive assembly to the upper case. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4656 Lift the hard drive assembly out of the upper case. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4657 Use the tip of a spudger to pull the fan cable connector straight away from its connector on the logic board. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4662 Use the tip of a spudger to move the cosmetic fan cover aside. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4663 Use the tip of a spudger to move the cosmetic fan cover aside. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4663 If you have the original version of the MacBook Air (A1237), refer to picture 1. Remove the following screws securing the heat sink to the logic board: One 5.9 mm Phillips screw. Two 1.9 mm Phillips screws. One 1.9 mm Phillips screw. If you have the A1304 version of MacBook Air, refer to picture 2. Remove the following screws securing the heat sink to the logic board: One 5.0 mm Phillips screw Five 1.9 mm Philips screws. One 2.5 mm Phillips screw. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4664 If you have the original version of the MacBook Air (A1237), refer to picture 1. Remove the following screws securing the heat sink to the logic board: One 5.9 mm Phillips screw. Two 1.9 mm Phillips screws. One 1.9 mm Phillips screw. If you have the A1304 version of MacBook Air, refer to picture 2. Remove the following screws securing the heat sink to the logic board: One 5.0 mm Phillips screw Five 1.9 mm Philips screws. One 2.5 mm Phillips screw. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4664 Lift the processor clamp off the heat sink. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4665 Deroute the microphone cable away from the channel in the fan. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4666 Lift the heat sink up off the logic board. Be mindful of the microphone cable when lifting the heat sink, as it can get tangled on the top edge of the fan. When you mount the heat sink back onto the logic board, be sure to apply a new layer of thermal paste. We have a guide that makes replacing the thermal paste easy. /Guide/Installing-MacBook-Air-Models-A1237-and-A1304-Heat-Sink/853/all#s4667