Serpentine Drive Belt; Checking; Replacing Belt And/Or Adjusting Tension - Mercury 350 MAG Manual

Serpentine Drive Belt

Inspecting the belts with the engine running may cause serious injury or death. Turn off the engine and remove the ignition key
before adjusting tension or inspecting belts.
d
a
With a seawater pump
a - Idler pulley
b - Water circulating pump pulley
c - Crankshaft pulley
d - Alternator pulley
e - Seawater pump pulley
f - Power steering pump pulley

Checking

1. Inspect the drive belt for proper tension and for the following:
• Excessive wear
• Cracks
NOTE: Minor, transverse cracks (across the belt width) may be acceptable. Longitudinal cracks (in the direction of belt
length) that join transverse cracks are NOT acceptable.
• Fraying
• Glazed surfaces
• Proper tension ‑ 13 mm (1/2 in.) deflection, with moderate thumb pressure, on the belt at the location that has the longest
distance between two pulleys.

Replacing Belt and/or Adjusting Tension

IMPORTANT: If a belt is to be reused, it should be installed in the same direction of rotation as before.
NOTE: Belt deflection is to be measured on the belt at the location that has the longest distance between two pulleys.
1. Loosen the 16 mm (5/8 in.) locking nut on the adjustment stud.
2. Turn the adjustment stud and loosen the belt.
3. If a new serpentine drive belt is required, remove the old belt and install a new belt onto the pulleys.
90-8M0050539 MAY 2011
eng
a
b
f
c
e
6116
WARNING
!
d
Without a seawater pump
mc75130-1
Section 5 - Maintenance
a
b
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c
f
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