Fru Replacement Notices; Screw Notices - Lenovo ThinkPad R51e Series Hardware Maintenance Manual

FRU replacement notices

This section contains notices related to removing and
replacing parts. Read this section carefully before replacing
any FRU.

Screw notices

Loose screws can cause a reliability problem. In the
ThinkPad computer, this problem is addressed with special
nylon-coated screws that have the following characteristics:
v They maintain tight connections.
v They do not easily come loose, even with shock or
vibration.
v They are harder to tighten.
v Each one should be used only once.
Do the following when you service this machine:
v Keep the screw kit (for the P/N, see "Miscellaneous
parts" on page 253) in your tool bag.
v Always use new screws.
v Use a torque screwdriver if you have one.
Tighten screws as follows:
v Plastic to plastic
Turn an additional 90 degrees after the screw head
touches the surface of the plastic part:
v Logic card to plastic
Turn an additional 180 degrees after the screw head
touches the surface of the logic card:
v Torque driver
If you have a torque driver, refer to the "Torque" column
for each step.
90 degrees more
(Cross-section)
180 degrees more
(Cross-section)
ThinkPad R50e, R51e and R52 Series

FRU replacement notices

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