Triumph Repair: Re-Torquing Head Bolts, rocker shaft, head gaskets

Question
Hi Howard,

Thanks again for all the good advice.  1966 TR4A.  How important/critical is it to re-torque the cylinder head after it has been off the engine?  About 1,000 mile ago my mechanic had the head off to do some minor work (this included a new head gasket). All was well until ~200 miles ago when I developed a fairly major oil leak. Could re-torquing fix this?

If so,
1. How difficult is this?  I have a 1/2" drive torque wrench with a 24" handle. The workshop manual calls for 100 ft-lbs. Does this require brute force?

2. Any tips/procedures/pitfalls to watch for?  My biggest fear is snapping a head bolt.

3. Does the valve train need to come off?

4. If so, will the valve clearances need to be reset?

5. BTW, can valve cover gaskets be re-used if in good shape or does it need to be renewed every time?

6. (Lastly!) the workshop manual say to torque the valve cover to only 2 ft-lbs(?)  Is that enough to seal it from leaking?

Thanks again

Bob

Answer
Hi Bob,
Some of the newer head gaskets claim they don't need to be retorqued but I like to "play it safe" and retorque at 500 to 1000 mi.
It must be done stone cold and start from the center studs and crisscross back and forth to get to each end of the head. To torque the head studs under the rocker shaft without removing the assembly you need a special "U" shaped adapter/box end wrench. 100 to 105 ft lb torque does require some grunt to pull.
If a head stud breaks off at 100 ft lbs, it was flawed anyway and could have broken when the engine was running.
Even with the special tool to torque the nuts under the rocker shaft, you still need to readjust the valves. All of this should have been covered by the original cost of removing and replacing the head.
Valve cover gaskets can be reused over and over again until you break it or it starts leaking. You can't put much torque on a valve cover. Most mechanics don't torque valve covers, they just snug them down. If you are not failure with what 2 ft lb of torque feels like try to borrow an inch lb torque wrench and pull 24 in lb on a bolt just to feel how much force that is. 2 ft lbs of torque on a large ft lb torque wrench would be impossible to get correct without breaking off a few bolts.
Howard