Subject: Crankcase and Related Parts Models: 911 SC 1983
Bulletin Number: 83 – 06
1983-84 Model Years
A new version crankcase is being used in production as of March, 1983.
Engine numbers are as follows:
911 SC 64D3717
911 Turbo (Canada) 67D0712
Part Numbers: Old New
911 SC 930.101.915.00 930.101.917.00
911 Turbo 930.101.916.00 930.101.918.00
To increase crankcase strength, the removable oil filter screen and cover plate with oil drain plug have been eliminated.

Fig. 1 Crankcase half

Fig. 2
Oil drain plug is now located on left side of crankcase
Oil pump
With new engine crankcase, a new oil pump is used. This oil pump has a filter screen on the oil pick-up pipe.
New Oil Pumps

Fig. 3 911 SC, P/N 911.107.008.05

Fig. 4 911 Turbo, P/N 930.107.008.04

Fig. 5 Old Oil pump
911 SC P/N 911.008.01
911 Turbo P/N 930.107.008.02

Fig. 6 Intermediate Shaft Bore Cover
Intermediate Shaft Bore Cover
A new intermediate shaft bore cover is also being used. { Fig.6 }. The cover is retained by 2 M6X16 mm hex head bolts and is sealed by an O ring.
Cover P/N 930.105.165.00
Seal P/N 999.701.658.40
Bolt P/N N010 287.1
New Repair Procedures

Parallel Alignment of Camshaft Sprockets
Because of the change in the intermediate shaft cover area, a new method of checking parallel alignment of camshaft sprockets is necessary.
Old Measuring Method:

Example: Measured distance A = 78.7 mm
For sprocket of cyl. 1 – 3, we have A + 54.8 mm = 133.5 mm
For sprocket of cyl. 4 – 6, we have A = 78.7 mm
New method

Distance A is measured from front edge of crankcase to face the intermediate shaft.
Design distances between sprockets:
- From face of intermediate shaft to face of rear camshaft sprocket {cyl 1 – 3 } = 98.07 mm
- From face of intermediate shaft to face of front camshaft sprocket {cyl 4 – 6} =43.27 mm
Design distance plus measured distance A = position of sprockets on camshafts.

Example: Measured distance A = 35.5 mm
For sprocket of cyl 1 – 3 we have:
A + 98.07 mm or
35.5 + 98.07 = 133.57 mm (+ 0.25 mm)
For sprocket of cyl 4 – 6 we have:
A + 43.27 mm or
35.5 + 43.27 mm + 78.57 mm (+0.25 mm)
Sprocket adjustment procedure is unchanged.
Normally, 3 shims underneath left camshaft sprocket.
Shim P/N 901 105 561 00
- 0.5 mm thickness
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