Teledyne Continental Motors, Inc.
TM
Standard
Practices
IOF-550 Permold Series Engine Maintenance Manual
C-15
1 April 2007
C-7.3. Size-on-Size Rosan
®
Stud Removal
To prevent damage to the engine cylinder, take precautions when removing a size-on-size
Rosan
®
stud.
Procedure
1.
Carefully cut the damaged stud flush with the cylinder head. Do not come in contact
with or mark the cylinder head.
2.
Score the remaining portion of the stud with a center punch.
3.
Locate the proper size primary removal drill directly over the center of the stud and
drill to the specified depth. The primary removal drill size and specified depths are
listed in Table C-1.
4.
Center the secondary removal drill over the small hole and drill to the specified depth
(Table C-1). This method should cut the engagement between the stud serrations and
the internal serrations of the lock ring.
Table C-1.
Rosan
®
Stud Primary & Secondary Removal Drill Diameters & Depths
Cylinder Exhaust Port Stud
Primary Removal Drill
Secondary Removal Drill
Basic Stud Number
Diameter
Minimum
Depth Diameter (+0.015)
Depth
(0.164 dia.)
SFC164
1/16(0.062)
0.250
3/16(0.188)
0.080
(0.190 dia.)
SFC190
1/16(0.062)
0.250
7/32(0.219)
0.090
(0.250 dia.)
SFC250
3/32(0.093)
0.250
19/64(0.296)
0.105
(0.312 dia.)
SFC312
1/8(0.125) 0.312
R(0.339)
0.120
(0.375 dia.)
SFC375
1/8(0.125) 0.375
13/32(0.406) 0.120
5.
The remaining lock ring will have a very thin wall. Carefully use a sharp punch to
break away the remaining portion from the cylinder head.
6.
Drive an “Ezy Out” bolt extraction tool into the small hole in the stud and apply
removal torque.
7.
Remove the stud and clean the hole.