pound along outside edge of left crankcase half. Run the length of thread so that it is both sides of bolt hole without touching each other. An alternate method of seal-ing is discussed in Service Instruction No. 1125.
NOTE
On engine with governor, hold the governor drive gear shaft is right half of crankcase with safety wire that can be removed when crankcase to fasten together.
7-68. Lower the right half of the crankcase so that the studs align properly with the left half. If necessary, tap the right half gently with a soft hammer to facilitate assembly. However, no difficulty will be encountered if the two halves are kept parallel while the right is being lowered onto the left. After the cases are together, tap the right half with a soft hammer to seat it securely all
around.
NOTE
When tapping crankcase with soft hammer as stated in paragraph 7-68 be careful that the camshaft gear is not jared out of time.
OVERHAUL MANUAL LYCOMING 76 SERIES AIRCRAFT ENGINES Section7
Figure 7-13. Checking Crankshaft End Clearance
7-69. Install all crankcase fastenings. Consult the ap-
the ap- plicable Parts Catalog for correct attaching parts
7-70. In order to insure uniform loading on the ma in bear-ings, it is necessary to tighten the studs and bolt s in the following sequence.
7-71. Install torque hold down plate (ST-222 or equ ivalent) at cylinder pads.
7-72. Install nuts on free ends of 1/2 inch thru-studs uds andusing the sequence specified in figure 7-14, tighten inch pounds (25 foot pounds).
7-73. Using the same sequence as specified in par ragraph 7-72, tighten the nuts on the thru-studs to 600 inch hpunds (50 foot pounds) torque.
7-74. Torque 3/8 inch nuts at front main bearing (4, figure 7-13) to 300 inch pounds (25 foot pounds).
7-75. Using the sequence specified (5 thru 10, figure 7-14), tighten 1/4 inch nuts at crankcase parting face to 98 -108 inch pounds (8 to 9 foot pounds).
7-76. Using any sequence tighten the remaining 1/4 inch nut at crankcase parting face 96 to 108 inch pounds (8 to 9 foot pounds).
7-77.Tachometer Drive. See figure 7-3. Place "o" ring seal
(10) over the tachometer adapter (8). Install tachometer drive seal retainer (11) and external retaining ring (12) on the adapter.
7-78.Oil and Vacuum Pump. See figure 7-1. Install the oil pump driving impeller (12) on the previously installed oil pump shaft (6). Place the driven impeller (4) in the crankcase. Install new oil seal (9) in the oil pump body.
Crankcase,Crankshaft
and Reciprocating Parts Place "o" ring seal (7) in groove of pump body. Install oil pump body over pump shaft and impellers. Secure with
plain washers, lockwashers, and attaching nuts. Tighten the attaching nuts in a random pattern and increasing steps until the final torque of 150 inch pounds is reached. After each step rotate the crankshaft to insure that the impellers are free and not binding. If any binding occurs, loosen the attaching nuts to free the impellers and retor-que using a different tightening sequence until crankshaft can be rotated and oil pump is free.
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