Middleby Marshall Gas Ovens PS53GS Gas - Manual (Page 22)

22
ENGLISH
IV. MAINTENANCE - EVERY 6 MONTHS
A. Check that the oven is cool and the power is disconnected, as
described in the warning at the beginning of this Section.
B. Check for excessive wear on the conveyor drive motor
brushes. The brushes should be replaced if they have
worn to less than 1/4" (6mm) in length. Be sure to replace
the brushes in exactly the same position.
C. For gas ovens, inspect and clean the burner nozzle and the
spark electrode assembly.
D. Check the conveyor drive shaft bushings and spacers.
Replace the components if they are worn.
E. Blower Belt
1. Remove the six screws shown in Figure 4-7. Then,
remove the rear panel from the oven.
2. Check the blower belt for the proper 1/4" (6mm) deflec-
tion at the center, and for cracking or excessive wear.
See Figure 4-7. Overtightening the belt will cause
premature bearing failure and possible vibrations. A
loose belt may also cause vibrations.
3. If necessary, adjust the tension of the belt by loosening
the four motor mounting bolts. Reposition the motor
as neccessary until the correct 1/4" (6mm) deflection
is reached, then tighten the bolts.
F. Lubricating the Blower Fan Bearings
1. Use a grease gun to lubricate the main blower fan
shaft bearings, as shown in Figure 4-7.
When lubricating the bearings:
• Use a high-quality NLGI #2, lithium soap grease with
petroleum oil, such as Middleby P/N 17110-0015.
• Add the grease slowly until a small bead of grease
is present at the seals. AVOID OVERGREASING.
Excessive greasing may cause harm to the bearing.
2. Manually turn the blower shaft by pulling on the belt to
purge the grease. Wipe off any excess grease.
3. Replace the rear panel onto the oven.
Remove six (6)
screws to remove
rear panel
Blower belt
Bearings
(2 total)
Blower motor
Loosen four (4) screws to adjust
motor position and belt tension
Figure 4-7 - Rear panel access
Grease fitting
(1 per
bearing)