MAINTENANCE
Item 7 – Tachometer Drive
A typical tachometer drive take-off
location is the camshaft drive gear
access cover on the front of the gear
case cover. Lubricate the tachometer
drive (if so equipped) every 150 hours
or 15,000 miles (24,000 km) with an
all-purpose grease. At temperatures
above –1 C (+30 F) use a No. 2
grade grease. Use a No. 1 grade
grease below this temperature.
Item 8 – Drive Belts
Belts should be neither too tight nor
too loose. Belts that are too tight
impose extra loads on the crankshaft,
fan and/or alternator bearings,
shortening both belt and bearing life.
Excessively overtightened belts can
result in crankshaft breakage. A loose
belt will slip and may cause damage
to accessory components.
PERSONAL INJURY
To avoid injury from rotating belts
and fans, do not remove and
discard safety guards.
Use a belt tension gage, such
as Kent-Moore
®
tool J 23586–B
(V-belt), J 23600–B (poly-V belt),
J 41251 (PowerBand
®
and 12–rib
poly-V belt), or equivalent, when
tensioning drive belts. Tension belts
to the values listed in Table 18.
V-Belts —
New standard V-belts
will stretch after the first few hours
of operation. Tighten V-belts as
listed in Table 18.
Fan Drive
Single Belt
2 or 3 Belts
80 – 100 lbs (356 – 445 N)
60 – 80 lbs (267 – 356 N)
Alternator Drive
Belt
New
Used
Two 1/2–in. V-Groove
125 lbs (556 N)
100 lbs (445 N)
2–Groove PowerBand
®
200 lbs (890 N)
150 lbs (667 N)
12–Rib Poly-V (50 DN Alternator)
350 lbs (1,557 N)
250 lbs (1,112 N)
Table 18
Drive Belt Tensioning
70
All information subject to change without notice. (Rev. 01/04)
6SE484
0401
Copyright © 2004 DETROIT DIESEL CORPORATION