DETROIT DIESEL 53
1.2 Cylinder Head
6. The cylinder head must be gradually and uniformly drawn down against the gaskets and seals to ensure a good seal
between the cylinder head and the block. Therefore, it is vitally important that the cylinder head be installed with the
utmost care.
7. Then, begin on the camshaft side of the head to take up the tension in the cam follower springs by tightening the
bolts lightly. Finally tighten-the bolts to 170-180 lb-ft torque with a torque wrench, about one-half turn at a time, in the
sequence shown in Fig. 6. Under no circumstances should the torque exceed the specified limits, otherwise the bolts
may become stretched beyond their elastic limits.
8.
over the oil drain holes in the cylinder head to prevent foreign objects from falling into the holes.
9.
f the injectors were not previously installed, refer to Section 2.1 or 2.1.1 and install them at this time.
10. tighten the rocker arm bracket bolts to 50-55 lb-ft torque.
CAUTION: There is a possibility of damaging the exhaust valves if the exhaust
valve bridge is not resting on the ends of the exhaust valves when tightening the
rocker arm bracket bolts. Therefore, note the position of the exhaust valve bridge
before, during and after tightening the bolts.
11. Align the fuel pipes and connect them to the injectors and the fuel connectors. Use socket J 8932-01 to tighten the
connections to 12-15 lb-ft torque.
CAUTION: Do not bend the fuel pipes and do not exceed the specified torque.
Excessive tightening will twist or fracture the flared ends of the fuel pipes and
result in leaks. Lubricating oil diluted by fuel oil can cause serious damage to the
engine bearings.
12. Set the injector control tube assembly in place on the cylinder head and tighten the bolts, finger tight only. When
positioning the injector control tube, be sure that the ball end of each injector rack control lever engages the slot in the
corresponding injector control rack. With one end of the control tube return spring hooked around an injector rack control
lever and the other end hooked around a control tube bracket, tighten the bracket bolts to 10-12 lb-ft torque.
13. After tightening the bolts, revolve the tube and see if the return spring pulls the injector racks out (no-fuel position)
after they have been moved all the way in (full-fuel position). Since the injector control tube is mounted in self-aligning
bearings, tapping the tube lightly with a soft hammer will remove any bind that exists. The injector racks must return to
the no-fuel position freely by aid of the return spring only. Do not bend the return spring to bring about this condition.
14. Install the fuel rod and the fuel rod cover (if used).
15. Remove the covers from the drain holes in the head.
16. Install the exhaust manifold and connect the exhaust piping.
17. Install the thermostat housing and the thermostat.
18. Install the air cleaners.
19. Connect the fuel lines.
20. Fill the cooling system and check for leaks.
21. With the throttle in the OFF position, crank the engine over to be sure that all of the parts function freely.
22. Before starting the engine, perform an engine tune-up as outlined in Section 14.
23. Refer to Section 13.1 and start the engine. After starting the engine, check all fuel line connections to ensure that no
fuel oil leaks into the cylinder head compartment to dilute the lubricating oil.
24. After the engine has been warmed up (to at least 160F), recheck the torque on the cylinder head bolts.
25. Recheck the exhaust valve clearance and the injector timing after the engine reaches normal operating
temperature.
26. Examine all fuel oil, lubricating oil and water connections for possible leaks. Tighten the connections, if necessary.
27. Install the valve rocker cover, using a new gasket.
July, 1970
SEC. 1.2
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