4.
Assemble the puller (P/N 64872) to the cranks
ept that
in the same manner as described in Step 1, exce
the large puller bushing is used instead of thhe small
puller bushing. Place the correct size counte rweightbushing on the puller bolt between the crankshafthaft ear
and large puller bushing. As the puller nut is tigghtened,
the bushing will be forced into place in the cra nkshaft
ear.
NOTE
The inside diameter of the crankshaft counterweight bushing is finished at time of manufacture and no further machining of the bushing is necessary. Care must be exer-cised when installing the bushing so that the finished in-side diameter is not damaged. Under no circumstances should the bushing be removed or installed by the use of a hammer and drift.
5. After the crankshaft counterweight bushing is in-stalled, check its alignment with the main bearing by
placing the crankshaft in vee blocks on a surface plate.
Install the wedge blocks P/N ST-212 in the bushing and
compare parallelism of the wedge blocks with the main
bearing journals. Bushing must be parallel with in .002
inch. Support the crankshaft in vee blocks at the jour-nals adjacent to the bushing location.
76 SERIES AIRCRAFT ENGINES
7-44. Counterweight Bushing Replacement. Consult the latest edition of Service Instruction No. 1143 for detail in-formation relative to rebushing counterweights an subse-quent inspection.
7-45. Connecting Rod Bushings. If the bushing in the small end of the connecting rod is worn beyond service limits, it can be removed and replaced by accomplishing the following procedure;
1.
Clamp the connecting rod on the connecting rod replacement block (P/N 64597) in such a manner that the small bushing in the rod is in alignment with the hole stamped "Remove Bushing". Use the connecting rod bushing removal drift (P/N 64535) and drive the bushing out of the rod. Move the connecting rod to the "Install and Burnish" position and clamp it securely in place. Using the replacement drift (P/N 64536) drive a new bushing in place in the rod. Be sure the split in the
bushing is located so that it is toward the piston end of rod and 45 off the centerline.
2.
Use a suitable arbor press and the connecting rod bushing burnisher (P/N 64580) to burnish bushing in place. Pass the burnisher completely through the bushing. Remove the rod from the holding block and finish bore the bushing to diameter shown in Table of Limits, reference 510. Check the bushing ID with finish ID gage (P/N 64767). Check alignment of the hole in the bushing with connecting rod parallelism and squareness gage (P/N 64530) as described in paragraphs 7-29 and
7-30. If the assembly does not meet the requirements shown in references 566 and 567, Table of Limits, the entire assembly must be replaced.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：莱康明发动机大修手册 OVERHAUL MANUAL LYCOMING 76 SERIES AIRCRAFT ENGINES(39)
