Apple IMAC Service Source - Page 85

Replacement Notes: Faraday cage: Look at the exploded view diagram during reassembly. First, attach the Faraday top cover to the top (OUTSIDE) of the Faraday cage as shown below; the Faraday top cover is keyed. Next, thread the neck cables through the hole in the Faraday cage and install the Faraday cage into the top plastic housing. Replace the screw that holds the plastic housing to the chassis. Attach the black neck cap screws to connect the neck to the chassis. Route the neck cables correctly in the base and replace the fan bracket retainer and three remaining neck cap screws. Warning: Whenever the bottom housing is opened for service, you must do two things: 1.You must clean the original thermal film from all thermal interface mating surfaces, and reapply thermal paste to the mating surfaces on the thermal pipe. 2. You must tighten the four torx screws on the bottom housing to a minimum of 17 in.-lbs. Use a torque driver (service tool 076-0899) to ensure that the thermal pipe is firmly mated with the top base. If you do not have a torque driver, you must make sure the screws are tightened by hand FIRMLY, BUT NOT FORCIBLY. Failure to follow these steps could cause the computer to overheat and damage internal components. Refer to the topic "Thermal Paste Application" for detailed information. 76 - iMac (USB 2.0) Take Apart Chassis (Faraday Cage)