General. Key-change locks require no disassembly to set new combi-
nations. To change the combination, the change key provided with the lock is
inserted into a keyhole in the back coverplate. Some key-change locks have
two reference marks on the dial ring. At the top of the dial ring is the
opening index. A changing index may be either slightly to the left or to the
right of the opening index, depending on the model. When a key-change lock
has only one reference mark, the single mark is used as both the changing and
opening indexes. Before the combination of any lock is changed, read the
entire change procedure carefully. Read installation instructions thoroughly
before beginning an installation procedure.
Sargent & Greenleaf Mounted Combination Locks
Combination Change Keys for the R6700, 8400, and 8500 Series, as
well as the 8470MP. To change the combination, these locks require one of two
different change keys (see Figure 1). For the four different backplate (back
cover) styles, see Figures 2 through 5. The installed backplate style on a
particular lock will determine the required change key. The first style, as
shown in Figure 2, has a flat backplate. The second, shown in Figure 3, has a
raised circular area. As depicted in Figure 4, the third has a raised
circular area with a recessed keyhole. The fourth, shown in Figure 5, has a
slightly recessed circular area.
The backplanes shown in Figures 2, 4, and 5 use the 6720 change key.
The 6720 key measures approximately 1-3/16 inches (30 mm) from the tip of the
key to the shoulder. The backplate shown in Figure 3 uses the 8400 change
key. The 8400 change key measures approximately 1-7/16 inches (36 mm) from
the tip to the shoulder. Figure 1 illustrates the difference in length
between the 6720 and 8400 change keys. Using the incorrect key will cause the
lock to malfunction, requiring the repair services of a locksmith.
Comparison Between the 6720 and 8400 Change Keys