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EMS-51 User Manual
v2 November 2019
M4x20
socket cap screws
7.2 – EMS-51: Removing the LF drive unit
TOOLS REQUIRED: 3mm Allen key
1.
Complete step 7.1 above to remove the grille.
2.
Using a 3mm Allen key, remove the four M4x20 socket cap screws that secure the drive unit. Ensure
that you collect both the spring washers and the flat washers as well as the machine screws.
3.
Lift the drive unit clear of the mounting hole and disconnect the cables – note the polarity for
reconnection (brown to LF positive, blue to LF negative).
4.
To replace the drive unit, ensure the 5” gasket is intact and complete – replace if necessary. Reconnect
the cables to the drive unit (note the polarity detailed above) and then sit the drive unit into its
mounting location, ensuring that the mounting holes line up.
5.
Replace the M4x20 socket cap machine screws with their spring washers and flat washers and ensure
all machine screws are started in their threads before tightening. Tighten opposing bolts, working
around the drive unit until all bolts are appropriately tightened. Be careful not to overtighten as this
will distort the drive unit chassis.
6.
Replace the grille as described above.
