tightening cylinder head

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bluff467
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Mon Aug 15, 2011 5:02 pm

I have now put my cylinder head back on my m20b25 and just want to know what the correct procedure is for tightening it up, ie: torque settings and do I need to do the 90% angle tightening aswell and also any other tips if anybody has any.

Chris
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Jim320i
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Mon Aug 15, 2011 5:34 pm

Have you bought new stretch bolts for this? I wouldnt re-use the old bolts!

If you have bought new, you should have a print out too of the correct procedure of which ones to tighten first etc... It works from the inside outwards but there is a certain way of doing it...

From memory they all neeed to be a certain torque first, then they all need to go the 90 degrees more once they are all set at the same tighteness. But if you havent got new bolts, make sure you do! They'll have the correct way of doing it in there.
Jim320i
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Mon Aug 15, 2011 5:40 pm

You'll also need a torque wrench and E14 torx socket from memory... Might be obvioius but thought I would add it as its a pain in the back side when you realise you havent got the right bits for the job!
Simon13
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Mon Aug 15, 2011 5:51 pm

30Nm and 90 degrees twice on each. going throught the sequence each time in the same order.
bluff467
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Mon Aug 15, 2011 6:10 pm

Much appreciated lads
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Brianmoooore
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Mon Aug 15, 2011 9:15 pm

After the initial torquing, put a mark on each bolt head at the twelve o'clock position with a permanent marker.
When you have finished tightening them, all the marks should be at six o'clock, and you won't get that have I/haven't I tightened every one, or have I missed one feeling.
bluff467
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Tue Aug 16, 2011 5:21 pm

Good advice lads, Cheers.
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bluff467
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Tue Aug 16, 2011 6:29 pm

I turned one of the bolts to 180 degrees on the first set of angle tightening in error, shall I slack it off and restart on that that one, ie: 30nm then 90 degrees and 90 degrees again?
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Brianmoooore
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Tue Aug 16, 2011 6:40 pm

If they weren't marked with a pen, you'd probably never know that you'd tightened it 180, and would possibly have broken it turning it another 90.
These are stretch bolts, so shouldn't be slackened and retightened. I'd leave it as it is.
bluff467
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Tue Aug 16, 2011 6:46 pm

Cheers
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