[W126 Coupe] broken head studs

[Doug Gavin]

James Smith wrote:

> I have a cylinder head with the exhaust manifold threaded studs broken 

> off in half from inproper removal. How does one usually go about 

> repairing this?

>

>

> Thanks a million!

>

>

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That's a tough break James but I think that you will find the the proper 
method when removing heads and replacing them is to tap and die the stud 
holes anyway so if you were to redo the heads in normal course you would 
be faced with a similar situation. The difference is that the broken 
studs will have to be pulled out with a reverse stud puller. This 
procedure of re tapping is recommended as I understand it, because the 
aluminum will not hold the new studs appropriately because the threads 
are weakened in the removal process and if one were to use the same 
threaded holes without re tapping one would be redoing the job anyway, 
and very soon. If you are having the heads done by a professional MB 
shop, this procedure is made very clear in the repair and replacement of 
cylinder heads. Hope this helps.