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Beemer head bolts breaking off

Ryon Warren asked:

What is the strength rating (i.e. the number stamped on
the head) of the recommended replacement head bolts.  I believe
the head bolts on my '81 528i are stamped 10.8, which if memory
serves correctly is 10,800 psi tensile strength.  All this talk of
head bolt failure has me slightly paranoid, and wonder if I should
change to higher strength bolts.

Bruce Toski replies:

I have the old one that broke off of my sister's 86 528e.  It appears to
be stamped 12.? on the head.  Best to check with a local BMW specialist
or call the Beemer parts dept. for # on new ones.  They are in the car
now.  I did not do the job due to time constraints, so I did not see the
strength stamping.  

Although the Alldata TSB mentioned that the newer bolts are higher
strength I am wondering... if BMW says the replacement bolts have a
lower number then maybe the old bolts were too brittle, wouldn't stretch
enuf. .... Not sure.  Anybody?
- -- 
Bruce Toski
Broward County Vo-Tech Automotive Instructor / Owner - Toski Tech
Preliminary Home page at:      http://www.fxn.com/users/b/btoski/
Most familiar with Audi 5000S automobiles and Wankel transportation
Ground support mechanic at Eastern Air Lines -  10 year veteran
	Thanks for nothing Frank ... Lorenzo and Borman that is.