Stag Head Tension
by Tim Buja from the Stag Repair Operations Manual
According to my Stag Repair Operations Manual, the head torquing procedure (12.29.27) is as follows:
------------------- |D B A C E | <--nuts on studs | | | | front of head | | |I G F H J | <--bolts -------------------
- Tighten cylinder head nuts as follows: A, B, C, D, E
- Tighten cylinder head bolts as follows: F, G, H, I, J
- Tighten two bolts securing front cover to cylinder head. Tighten 1 and 2 to torque 45 to 55 lbf ft (6.2 to 7.6 kgf m)
Note: Fit cylinder head studs to full depth of thread, finger-tight.
The torque wrench settings in the front of the ROM list the following:
|Cylinder head attachment bolt:||7/16″ U.N.C.||7.6 kgf m||55 lbf ft|
|Cylinder head attachment stud:||7/16″ U.N.C.||7.6 kgf m||55 lbf ft|
|Timing cover to cylinder head:||5/16″ U.N.F.||2.8 kgf m||20 lbf ft|
In addition, the ROM procedure for refitting the cylinder head (12.29.10) specifies a torque figure of 55 lbf ft (7.6 kgf m) for the nuts and bolts, and also includes the following:
- After 1600 kilometers (1000 miles) running, recheck the cylinder head fixings for correct tightness, as follows.
- With the engine cold and working in sequence shown in Operation 12.29.27, slacken each fixing in turn, approximately one flat, then re-tighten to the correct torque figures.
Triumph Stag Repair Operations Manuals are currently available from EWA in New Jersey, USA or directly from the publisher ( Robert Bentley ). I have done an Alta Vista search on “Triumph Stag” and it found a link directly to the Robert Bentley site where you can order the manual as well as the original BL Spare Parts Catalog.
Tim Buja, TKBuja@insightbb.com
80 TR8, 73 Stag, 72 TR6