GMC 1976 ZEO 6083 Maintenance Manual page 652

13- 2 RADIATOR AND COOLANT RECOVERY SYSTEM
RADIATOR
CAP-*,.
UPPER- RADIATOR
SUPPORT CHANNEL
DRAIN COCK
600- MOUNTING PAD (LOWER)
FAN SHROUD SEAL RETAINER STRAP
SHROUD TO VENTURI RING SEAL
RADIATOR FAN SHROUD
25-30 FT. LBS .
RADIATOR SUPPORT MOUNTING BRACKET
LOWER RADIATOR SUPPORT ASM.
A-1981
Water under moderate pressure should be di-
rected from behind core to force debris out in oppo-
site direction of its entrance. Water should be
directed in line with fins, not sideways, to reduce
possibility of bending fins.
5. Inspect radiator mounting pads for deteriora-
tion and replace as required .
6. Inspect for proper clearance between fan
blades, radiator core venturi ring, and shroud . Check
fan attaching bolts for tightness and observe align
ment of fan blades in relation to each other . Replace
fan if any blade is bent . Distance between blades and
venturi ring should be equal around entire perimeter
of the ring . If adjustment is required, venturi ring
attaching bolts may be loosened and the ring shifted
as necessary to provide proper clearance.
7. Check radiator filler cap seals for evidence of
cracking or separation . Replace as required .
8 . When coolant loss is evident or engine over-
heating occurs, the damaged or clogged radiator
should be serviced by a radiator specialist or replaced
with a new one. Efficient repair of radiators requires
the use of special tools and equipment as well as
provisions for making proper tests. If radiator core
requires painting, spray with special radiator paint;
do not use paint mixed with oil, as oil mixed paint
will form an insulation and prevent efficient dissipa-
tion of heat .
Figure 1-Radiator Assembly (Typical)
RADIATOR MOUNTING
Refer to Figure 1 for mounting details of radiator
support, radiator core, fan shroud and venturi ring .
RADIATOR REPLACEMENT
1 . Drain radiator by opening drain cock assembly
at lower corner of radiator assembly (location of
drain cock shown in figure 1) .
2. If unit is equipped with air conditioning, per-
form the following:
a. Remove front grille .
b. Disconnect air conditioning condenser
from radiator .
3 . Disconnect radiator overflow tube and upper
radiator hose .
4. Raise vehicle.
5 . Disconnect lower radiator hose transmission
cooler and engine oil cooler lines.
6. Disconnect upper radiator support channel as-
sembly .