Oetiker Screw Clamps; Constant-Torque Hose Clamps On Charge Air Cooler (Cac) System - PREVOST H3-41 Maintenance Manual

SECTION 05a: H3 SERIES COOLING SYSTEM
FIGURE 10: COOLANT LINE AT PUMP INLET
3.1.1

Oetiker Screw Clamps

FIGURE 11: OETIKER CLAMP (image: oetiker)
Assembly recommendations
1. Turn screw anti-clockwise until it stops at the
"D" nut.
2. For radial installation or change of diameter,
unlatch the interlock.
3. Position the open clamp around the hose.
Locate the tongue in the groove and position
the apertures of the mechanical interlock over
the mating features. Engage the interlock at
the smallest possible diameter.
4. Tighten the screw to the required torque:
•
Spring without color identification
TORQUE: 8-9 lb-in (0.9-1.02 Nm)
•
Green spring
TORQUE: 12-18 lb-in (1.36-2.03 Nm)
5. A gap of 3 mm should exist between the D-
nuts. This ensures that there is sufficient
movement for the clamp to reduce in
diameter when the spring
of the self-tensioning clamp
expands during contraction
of the hose. If the gap
between the D-nuts is less
than the recommended 3
mm, proceed to step 6.
PA1615 Maintenance Manual All Series | Section 05a revised September 2016
12
6. Turn the screw anti-clockwise to loosen the
Self-Tensioning Screw Clamp.
7. Relocate the interlock in the next smaller
diameter position.
8. Tighten the screw to the required torque.
3.2 CONSTANT-TORQUE HOSE CLAMPS
ON CHARGE AIR COOLER (CAC)
SYSTEM
If for any reason hose clamps need to be
replaced; install and tighten hose clamps to
specified torque (dry) (Figure 12).
TORQUE: 4.5-5.5 lb-ft (6.1-7.46 Nm)
05037
FIGURE 12: CHARGE AIR COOLER HOSE CLAMPS
CAUTION
The hose clamps will break if over-tighten. Do
not over-tighten,
weather when hose has contracted.
Maintenance
Since the constant-torque clamp automatically
adjusts to keep a consistent sealing pressure,
there is no need to re-torque hose clamps on a
regular basis. During vehicle operation and
shutdown, the screw tip will adjust according to
the temperature and pressure changes.
Checking for proper torque should be done
at room temperature.
especially during cold