General
1-14
Poor quality or damaged Phillips
screwdrivers can back out (cam out)
and round over the screw head. In
addition. Weak or soft screw materials
can make removal difficult. The best
type of screwdriver to use on a Phillips
screw is the ACR Phillips II screwdriver,
patented by the horizontal anti-cam out
ribs found on the driving faces or flutes
of the screwdriver’s tip (figure 4).
ACR Phillips II screwdrivers were
designed as part of a manufacturing
drive system to be used with ACR
Phillips II screws. Many tool companies
offer ACR Phillips II screwdrivers in
different Tip size and interchangeable
bits to fit screwdriver bit holders.
Note:
Another way to prevent cam out and
to increase the grip of a Phillips
screwdriver is to apply valve
grinding compound or permute
screw ＆ socket Gripper onto the
screwdriver tip. After loosening or
tightening the screw, clean the screw
recess to prevent engine oil
contamination.
Wrenches
Open-end, box-end and combination
wrenches (figure 5) are available in a
variety of types and sizes.
The number stamped on the wrench refers
to the distance of the fastener head.
The box-end wrench is an excellent tool
because it grips the fastener on all sides.
This reduces the chance of the tool
slipping. The box-end wrench is designed
with either a 6 or 12-point opening. For
stubborn or damaged fasteners, the 6-point
provides superior holding because it
contacts the fastener across a wider area at
all six edges. For general use, the 12-point
works well. It allows the wrench to be
removed and reinstalled without moving the
handle over such a wide area. An open-end
wrench is fast and works best in areas with
limited overhead access. It contacts the
fastener at only two points and is subject to
slipping if under heavy force, or if the tool or
fastener is worn. A box-end wrench is
preferred in most instances, especially
when braking loose and applying the final
tightness to a fastener. The combination
wrench has a box-end on one end and an
open-end on the other. This combination
makes it a convenient tool.
To Next Page
