TDC Valve positions

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bluff467
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Sun Aug 14, 2011 7:37 am

I am going to put my cylinder head back on to the engine today, m20b25, but I just want to make sure that the valve positions are right before I do so. No 1 and 6 pistons are up, so should the valves for no 1 and 6 be closed when I put the cylinder head back on?
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E30_Crazy
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Sun Aug 14, 2011 9:45 am

Just turn the crank about 25-30* clockwise and all pistons should be at some level of mid-bore. Then get the head on, and tightened down. Turn the cam gear until the notch and line are inline (TDC for cam) and then turn the crank back the 25-30* to TDC, and it will be all lined up for the cam belt.
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Brianmoooore
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Sun Aug 14, 2011 11:16 am

bluff467 wrote:should the valves for no 1 and 6 be closed when I put the cylinder head back on?
One set or the other should be partly open.
As said above, never put a head on with any piston completely up.
bluff467
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Mon Aug 15, 2011 6:14 pm

When I line the marks up on the cam does it matter which valves are open and which are close, or are the valves automatically in the right sequence when the marks are lines up?
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HairyScreech
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Mon Aug 15, 2011 6:16 pm

the timing marks should be tdc number one cylinder, thus if you put both the cam and crank to there timing marks you cant really get it wrong.
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822

m3.3.1 m20 thread - now running, chip needed - any volunteers?
http://www.e30zone.net/modules.php?name ... =viewtopic&
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