[TR] broken TR-4 head

[Greg Solow]

It looks like there is still plenty of threaded hole left.  The area around 
the intake port does not get very hot.  coat a stud with a light coat of 
grease, screw it into place. Fill the broken area with JB Weld or another 
good steel epoxy filler. Let the epoxy harden, then remove the stud and 
carefully file the surface flat. That should make it serviceable.
                                                                             
                                Greg Solow