Automatic Belt Tensioner Bushing Wear; Belts And Idlers Visual Inspection; Engine Protection Strategy - PREVOST H3-41 Maintenance Manual

I= IDLER
T= TENSIONER
FIGURE 15: IDLER AND AUTOMATIC BELT TENSIONER
ON ALTERNATOR DRIVE
3. Spin all idler pulleys, I-1 thru I-8, plus the
idlers that are part of the automatic belt
tensioners T-1 thru T-3.
4. Listen if some idlers are noisy and check for
play in the bearings by hand.
5. Replace noisy idlers or if a play is found.
Replace the automatic belt tensioner as a
complete unit.
6. Record the results of the inspection.
4.2 AUTOMATIC BELT TENSIONER
BUSHING WEAR
Automatic belt tensioner bushing wear may
results in belt misalignment.
1. Check the automatic belt tensioner T-1 thru
T-3.
2. Pry the automatic belt tensioner arm and
check for a play between the arm and the
spring case (see image below).
FIGURE 16: CHECKING BUSHING WEAR
3. If bushing wear is suspected, remove the
4. Replace the automatic belt tensioner if found
5. Record the results of the inspection.
4.3 BELTS AND IDLERS VISUAL
1. Inspect
2. Visually inspect all idlers for signs of
01226
3. Record the results of the inspection.
Visually inspect belts and idlers for signs of
deterioration, cracks, frayed material at the
intervals specified by the Lubrication And
Servicing
LUBRICATION & SERVICING.

5. ENGINE PROTECTION STRATEGY

The engine protection system will automatically
derate or derate and stop the engine when
certain engine conditions reach a critical stage.
In the event of a serious fault, the red STOP
telltale light comes on and an audible alarm will
sound if the engine is running.
Prior to an actual automatic shutdown, the
engine will automatically derate, go to idle, and
then stop in 30 seconds.
ENGINE PROTECTION LOGIC (with yellow
CHECK or red STOP telltale light)
High engine coolant temperature
High engine oil temperature
Low engine oil pressure
High crankcase pressure (rate of
change)
Low coolant level
PA1615 Maintenance Manual All Series | Section 01 revised April 2017
SECTION 01 : ENGINE
tensioner. Inspect the tensioner for any signs
of wear. Check for bearing noise as well as
metal to metal contact between the arm and
spring case which is a sign of bushing wear.
Check for cracks in the tensioner body.
defective.
INSPECTION
drive belts
material, missing chunks
abrasion and peeling. Replace belts if
damaged.
deterioration, loose fasteners, etc.
MAINTENANCE
Schedule
for cracks, frayed
in the belt,
in Section 24:
Shutdown
Shutdown
Shutdown
Shutdown
Derate only
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