Subject: Removing Broken Head Studs Models: 911/930 All Years
Bulletin Number: 83 – 03
If a cylinder head stud, (see fig. 1), is broken above the threads in the crankcase, the following should be applied:
Repair Procedure
- Grind broken stud flat
- Center punch stud
- Using a ¼ inch. (6.35mm) carbide tip drill bit in a drill press, drill approximately 15mm into the stud.
- Drive a Number 3 Snap-On screw extractor approximately 200 degrees Celsius to loosen the grip of the loctite. It is very important to heat the crankcase properly.
- Turn out the broken stud.
- Retap threads in crankcase and install new Dilavar with Loctite 270. Part Number
928.101.921.00

Figure 1. Broken Head Stud
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