Cadillac 60 Series 1963 Shop Manual page 213

9-20
ENGINE MECHANICAL
15. Valve Lifter Leak-
Down Rate Checking
The Valve Lifter Leak-Down Rate Tester,
J-3074, is used to obtain a comparison of leak-
down rates of hydraulic valve lifters without
removing them from the engine. With this tool,
a feeler gage of a given thickness is placed be-
tween the rocker arm and the valve stem, causing
valve spring pressure to force oil out of the
lifter.
A spring attached to the tool and compressed
against the valve spring retainer ejects the feeler
gage when the lifter has leaked down enough to
allow the valve to seat. By observing the length
of time required by each lifter to leak-down
the thickness of the feeler gage, a faulty lifter
or lifters can be easily located.
Use the following procedure:
1. Operate engine to allow lifters to fill
with oil.
2. Turn off engine. Remove distributor cap
and rotate crankshaft so that rotor is at No. 1
firing position.
3. Remove carburetor air cleaner.
4. Disconnect positive battery cable.
5. If car is equipped with Air Conditioner, re-
move compressor as described in Section 13,
Note 29a.
6. Remove water control valve from retainer
bracket by removing spring clip, and r e m o v e
heater inlet hose from hose retainer clamp on
right rocker arm cover. Do not disconnect heater
hoses from water control valve.
7. Disconnect spark plug wires at plugs and
remove rocker arm covers.
Valve Lifter
Leak Down
Tester Tool
No. J-3074
TO
M
•j R^jS
HP**;
8. If car is equipped with Cruise Control, dis-
connect accelerator linkage rod at control unit.
9. Check each lifter listed in following table:
Rotor at No. 1 firing position (pointing toward
No. 1 cylinder). Check:
1 Exhaust
1 Intake
3 Intake
3 Exhaust
5 Intake
7 Exhaust
2 Exhaust
4 Intake
8 Intake
8 Exhaust
10. Insert feeler gage of tool between valve
stem and rocker arm and at the same time,
compress tool "pop-out" spring to its stop
against valve spring retainer, Fig. 9-20.
NOTE: Install tool as quickly as possible
to eliminate any unnecessary lifter leak-down.
11. Note interval of time during which tool is
held in place by valve spring pressure. The noisy
lifter or lifters will have the shortest leak-down
time.
12. Connect positive battery cable, install dis-
tributor cap, connect spark plug wires, and
operate engine to allow lifters again to fill up with
oil.
13. Turn off engine, remove distributor cap
and rotate crankshaft so that rotor is at No. 6
firing position. Disconnect spark plug wires and
positive battery cable.
14. Check each lifter listed in following table:
Rotor at No. 6 firing position (pointing toward
radiator cap). Check:
5 Exhaust
7 Intake
2 Intake
4 Exhaust
6 Exhaust
6 Intake
Fig. 9-20 Valve Lifter Leak-Down Rate Checking
15. Install rocker arm covers, using new
gaskets, and connect spark plug wires at plugs.
Tighten rocker arm cover screws to 28 inch-
pounds.
16. If car is equipped with Cruise Control,
connect accelerator linkage rod to control unit.
17. Install distributor cap.
18. Install water control valve on retainer
bracket and secure with spring clip. Secure heater
inlet hose to hose retainer clamp on right rocker
arm cover.
NOTE: If car is equipped with Air Condi-
tioner, install compressor as described in Sec-
tion 13, Note 29b.
19. Install carburetor air cleaner.