<VV> Upper Head Stud - Help!

[BobHelt at aol.com]

In a message dated 8/25/2010 1:54:56 P.M. US Mountain Standard Time,  
jay.pitchford at gmail.com writes:

I  ordered six Clark's .003 top studs, but upon installation they all
flexed  badly and wouldn't reach 30 ft-lbs; one spun freely and one
pulled out  completely. I ordered .006 studs, getting all five GM NOS
studs they had  left in stock and one Clark's .006 stud.

My mechanic put 1/2"  heli-coils in the spun and pulled holes mentioned
above, but he tried to  re-use the original stock studs with Locktite.
He ended up pulling both  heli-coils back through and stripping the
threads in the pulled stud  hole.



Hello Jay,
 
There are several mistakes you are making.
 
First please get a new mechanic. He should NEVER use 1/2 inch Helicoils for 
 head studs. The alum thread is one inch long and he must use a helicoil or 
 TimeSert that engages all of these threads. No wonder he pulled the 
Helicoils  out. That was a dumb thing on his part. Helicoil provides inserts that 
are 0.93"  long as well as ones longer. He could have also used TWO 1/2" 
inserts end-to-end  too.
 
Now when an insert pulls out like your did, you MUST get an oversize  
insert. The quickest way probably is to contact Larry Claypool and get them from  
him. What he is going to provide is essentially, a 1" long 9/16" bolt that 
has  the head removed. This "bolt" will have a 3/8" hole drilled thru it and 
tapped  for a head stud. To install, you will tap the hole in the block 
with a coarse  9/16 tap. Use loctite to prevent oil seepage. You may have to 
run a die over the  case end of the stud to make it fit the insert.
 
You probably should use the Claypool inserts in all six upper stud  holes.
 
Regards,
Bob Helt