Posted by L.A.B. on 4/26/2012, 11:49 am, in reply to "retorquing cylinder head"
82.22.53.127
<Anyway found that head has been not retorqued properly by the same 'expert' mechanic, inner bolts quite loose (tappets also not set to the right values).>
It isn't unusual for the inner head fasteners (T140 are socket nuts, not bolts) to slacken off and the head torque often needs re-checking at least two or three times after a top end rebuild if a composite gasket is fitted.
Unfortunately the inner fasteners may still loosen, as the 71-2598 washers are not wide enough to adequately spread the torque loading so the soft alloy of the cylinder head deforms and sinks and the fasteners loosen. If the inner fasteners continue to slacken then the inner washers can be replaced with wider 82-2184 washers.
<Should you back the bolts off say a half turn before retorquing? I ask because it seems as though the outer bolts have stuck a little through corrosion.>
Backing off by 1/8 or 1/4 turn is usually enough.
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