Middleby Marshall PS500 - Manual (Page 20)

20
ENGLISH
III. MAINTENANCE - EVERY 3 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. Vacuum both of the blower motors, and their surrounding
compartments, using a shop vacuum.
C. Tighten all electrical control terminal screws.
D. Split Belt Disassembly and Cleaning
For split belt ovens ONLY, disassemble, clean and lubri-
cate the conveyor shaft components as described below.
1. Remove the motor shroud, conveyor extensions, and
conveyor as described in Part II, Monthly Maintenance.
2. Remove the master links from each conveyor belt.
Then, roll the belts up along the length of the conveyor
to remove them from the frame.
3. Remove the two conveyor adjustment screws from the
idler end of the conveyor frame, as shown in Figure 4-
5.
4. Remove the idler shaft assembly from the conveyor.
5. Pull apart the two sections of the idler shaft. Clean the
shafts thoroughly using a rag. Then, lubricate both the
extended shaft and the interior of the hollow shaft using
a light food-grade lubricant.
CAUTION
DO NOT lubricate the shafts using WD40 or a similar
product. This can cause the shafts to wear rapidly.
6. Before reassembling the shafts into the conveyor
frame, check that they are oriented properly. Remem-
ber that unequal-width split belt ovens should AL-
WAYS have the narrower belt at the front of the oven.
7. Reassemble the idler shaft into the conveyor. Make
sure that the bronze washer is in place between the two
sections of the shaft. See Figure 4-7.
8. Replace the conveyor adjustment screws as shown in
Figure 4-5. To allow the conveyor belt to be reinstalled
later, do not tighten the screws at this time.
9. Loosen the set screw on both of the conveyor drive
sprockets. Then, remove the sprockets from the shaft.
10. Loosen the locking collar set screw, as shown in
Figure 4-6.
11. Push the drive shaft to the right, then lift it free of the
conveyor frame. Then, disassemble and lubricate the
two sections of the drive shaft as described in Step 5.
12. Before reassembling the shafts into the conveyor
frame, check that they are oriented properly. Remem-
ber that unequal-width split belt ovens should AL-
WAYS have the narrower belt at the front of the oven.
13. Reassemble the drive shaft into the conveyor. Check
that the nylon spacer is in place, as shown in Figure 4-
7. Also, check that the bronze washer is in place
between the two sections of the shaft.
14. Replace the drive sprockets. Reassemble the belts
and master links onto the conveyor, and replace the
conveyor in the oven.
15. Reassemble the motor shroud and conveyor exten-
sions onto the oven.
Figure 4-5 - Split Belt Idler Shaft
Figure 4-6 - Split Belt Drive Shaft
Figure 4-7 - Washer and Spacer
Conveyor
adjustment
screw
Locking collar
Bronze washer on
BOTH idler and
drive shafts
Nylon spacer
on drive shaft
ONLY
SECTION 4 - MAINTENANCE
16 Check the tension of the conveyor belt as shown in
Figure 2-10 (in Section 2, Installation). The belt should
lift between 75-100mm. If necessary, adjust the belt
tension by turning the conveyor adjustment screws.