Awe naw !!!!

New to the E30 Zone, well come and introduce yourself.
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Dunspannerin
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Thu Mar 14, 2019 8:16 pm

Hi guys just checked/adjusted valve clearances on my 320 I horror sitting quietly under the rocker cover A BOLT HEAD HEX engine running fine then and now anyone else come across this ?
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Brianmoooore
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Thu Mar 14, 2019 10:14 pm

Not unusual, and not a serious problem if no damage has been done. (I'm assuming it's one of the cylinder head bolts.)
BMW sourced their original head bolts from three sources. The bolts from one of these sources turned out to be susceptible to fracturing just under the head, but there is no way of telling which of your bolts are the suspect ones. It might be just the one that has failed, it might be a few of them, or it might be all of them. For this reason, the cylinder head bolts on any M20 that have hex. heads should be replaced ASAP.
Now the good news. There is no reason to remove the cylinder head or do any dismantling more than you have. The bolts can be replaced one at a time, in sequence, with the current torx. headed stretch bolts.
The only potential problem you may have is removing the remains of the broken bolt, but this should unscrew easily if you can find a way to turn it. A reverse cutting drill bit is the easiest way. It should pop out the instant the drill bites.
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Dunspannerin
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Thu Mar 14, 2019 10:24 pm

Thanks for a reassuring prompt reply Brian yes it is a head bolt and all seems to be running fine I take it the bolts are available from BMW
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Brianmoooore
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Thu Mar 14, 2019 10:52 pm

Bolts are available from BMW and other sources. They are stretch bolts, which must be tightened to a specific torque initially, then angle torqued twice through 90 degrees each. I recommend marking the head with a permanent marker after the initial tightening, so that you can be sure you haven't missed one of the 90 degree turns when you've finished.
These bolts are designed to permanently stretch slightly when fitted, so are supposed to be used once only.
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Dunspannerin
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Thu Mar 14, 2019 11:10 pm

That's great thanks again the central locking fault will just have to wait cheers
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Brianmoooore
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Thu Mar 14, 2019 11:26 pm

Dunspannerin wrote:
Thu Mar 14, 2019 11:10 pm
That's great thanks again the central locking fault will just have to wait cheers
Red/black wire mod?
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Dunspannerin
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Thu Mar 14, 2019 11:40 pm

I'm gonna try that then the thermal fuse in the central unit it just stopped working both door buttons wont move with the key puzzling??
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