Quote:
Originally Posted by Ozzie335i
Likely they did not replace the one time use bolts. Are replacements listed on your bill? If not, well.
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The OFH bolts are not one-time-use aluminum. They are steel and can be reused. The cylinder head is aluminum and the OFH is aluminum. Steel does not react with aluminum as it does with magnesium, which is why the OFH bolts are steel. BMW uses aluminum bolts for items that bolt to the magnesium engine block, because steel bolts will have a galvanic reaction with the magnesium. The '06 N52 uses aluminum bolts for attaching the magnesium valve cover to the aluminum cylinderhead because the
valve cover is magnesium. The later N52 with the plastic valve cover uses steel bolts to attach the valve cover to the aluminum cylinder head.
The OP's engine has a broken head bolt, which the N52 is well known to have a problem with. The fractured head bolt has nothing to do with the OFHG repair and is just coincidental that he noticed it post replacement of the OFHG. The repair is quite easy and just requires extraction of the bolt shaft and replacement. There are two head bolts under the valve cover at the front of the head at the timing case that also can break in a similar fashion.
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A manual transmission can be set to "comfort", "sport", and "track" modes simply by the technique and speed at which you shift it; it doesn't need "modes", modes are for manumatics that try to behave like a real 3-pedal manual transmission. If you can money-shift it, it's a manual transmission. "Yeah, but NO ONE puts an automatic trans shift knob on a manual transmission."