Chevrolet 70 1969 Series, Shop Manual

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ENGINE C O O L IN G SYSTEM 6K-8
1 Cover Bolt
2 Cover
3 Cover Gasket
4 Upper Plate
5 Element
6 Lower Plate
7 Spring
8 Filter Body
9 Plug
Figure 5—Water Filter Assembly (TypicalI
7. Remove vise grips from filter hoses. Start
and operate engine until water in cooling system
is warm. Check for air lock in filter. If cover of
filter becomes warm no air-lock condition exists
in system. If cover remains cool, vent system
same as for a hot water heater system.
8. Refill system to proper level.
9. IM P O R T A N T : Make sure that filter body is
grounded, otherwise electro-chemical action of
filter element will be reduced.
OIL COOLER
1. Disconnect oil cooler lines at oil filter.
2. Back-flush oil cooler and lines using clean
solvent and compressed air. D O N O T E X C E E D
100 PSI air pressure.
3. Remove all remaining cleaning solvent from
the system with compressed air.
4. Flush system again with the same type of
oil normally circulated through the cooler.
5. Test flow of oil through cooler. If flow is
not restricted, reconnect oil cooler lines. If flow
is restricted, have oil cooler element replaced by
a radiator specialist.
Refer to current applicable Detroit Diesel
Manual for information on oil cooler used on 6 V-53
engines. The following information pertains to all
engines using oil cooler except 6V-53 engine.
Models equipped with oil cooler use the type
of oil cooling system shown in figure 6. Oil is
filtered, circulated through oil cooler, and re­
turned to engine.
If engine difficulties are encountered and there
is suspicion that foreign matter has entered the
oil cooler, the oil cooler and connecting lines must
be flushed before engine is put back into operation.
Oil cooler, located at bottom of radiator core,
should be flushed in the following manner:
Figure 6—Oil Cooler Circuit IAII Models
Except with 6V-53 EngineI
CHEVROLET SERIES 70-80 H EAVY DUTY TRUCK SH O P M A N U A L