Without a seawater pump
a - Alternator pulley
b - Water circulating pump pulley
c - Crankshaft pulley
d - Belt tensioner
e - Power steering pump pulley
Serpentine Belt Failure Identification
Appearance
Description Cause Solution
Abrasion
Each side of the belt appears
shiny or glazed. Severe
condition: Fabric is exposed.
Belt is in contact with an object.
Can be caused by improper belt
tension or tensioner failure.
Replace the belt and
inspect for contact with an
object. Verify the belt
tensioner is functioning.
Pilling
Belt material is sheared off from
the ribs and builds up in the belt
grooves.
There are a number of causes
including lack of tension,
misalignment, worn pulleys, or a
combination of these factors.
When pilling leads to belt
noise or excess vibration,
the belt should be
replaced.
Improper install
The belt ribs begin separating
from the joined strands. If left
unattended, the cover will often
separate, causing the belt to
unravel.
Improper belt installation is a
common cause of premature
failure. One of the outermost belt
ribs is placed outside the pulley
groove, causing a belt rib to run
without a supporting or aligning
pulley groove.
The belt life has been
severely limited and
should be replaced
immediately. Ensure all
ribs of the replacement
belt fit into the pulley
grooves. Run the engine.
Then, with the engine off
and battery disconnected,
inspect the belt for proper
installation.
Misalignment
Sidewalls of the belt may appear
glazed or the edge‑cord may
become frayed and the ribs are
removed. A noticeable noise
may result. In severe cases, the
belt can jump off the pulley.
Pulley misalignment. Misalignment
forces the belt to kink or twist while
running, causing premature wear.
Replace the belt and verify
the alignment of the pulley.
Section 4 - Maintenance
Page 70 90-8M0128973 eng MAY 2017
To Next Page
Loading...
Need help?
General