User Manual

SERIES 50 OPERATOR'S GUIDE
V-Belts — New standard V-belts
will stretch after the first few hours
of operation. Tighten V-belts as
listed in Table 18. Ru n the engine
for 10 to 15 m inutes to seat the belts,
then readjust tension. Check and
retension belts after 1/2 hour and
again after 8 hou rs or 250 miles (400
km) of operation. Thereafter, check
the tension of the drive belts every
100 hours or 6,000 miles (10,000 km)
and adjust, if necessary.
If a belt tension gage is not available,
adjust the belt tension so that a firm
push with the thumb, at a point
midway betw een the two pulleys, will
depress the belt .50 in. – .75 in. (13
– 19 mm).
2-Groove PowerBand — The
2-groove PowerBand® is used with
the 50 DN alternator. To provide
proper running tension for the belt,
current Series 50 engines use an auto
belt tensioner, which requires no
adjustment. See Figure 14.
Earlier-built Series 50 engines have
a manual belt tensioner assembly.
See Figure 15.
Tighten a new PowerBand® drive belt
to 2 00 lbs (890 N), t hen run the engine
for 10 minutes at 1200 rpm. Stop the
engineandallowa10–15minute
cool down period. Check tension. If
less than 150 lbs (667 N ), retension
to 150 lbs (667 N). Fo llowing initial
tensioning, measure belt tension
every month or every 7,500 miles
(12,000 km ), whichever comes first.
Retension belt to 150 lbs (667 N) at
these intervals.
Figure 14 Auto Belt Tensioner
Assembly with 50 DN
Alternator
Figure 15 Manual Tensioner
Assembly with 50 DN
Alternator
All information subject to change without notice. (Rev. 01/04) 73
DDC-SVC-MAN-0058 Copyright © 2004 DE TROIT DIESEL CORPORATION