M20 valve clearance conundrum.

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jamesdark
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Post Sat Apr 08, 2006 11:32 pm

Hello all,when i bought my 325 it was very very ticky/rattly i adjusted the valve clearances and apart from the usual injector tick all was quiet.
Gradually over the following couple of weeks it got noisier and noiser untill it sounded as bad as it did before i had done it, so about a week ago i did them again, and all was quiet,but they have started getting noisier again.
Does anyone have any suggestions or am i going to have to do the valve clearances every two weeks?
I have checked the camshaft and there is no wear to speak off all the lobes are spot on and not worn down or anything.
Any ideas would be great.
charlE30
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Post Sun Apr 09, 2006 9:12 am

Might sound daft but are you tightening them up to the right torque?? 10 Nm with 0.25mm clearance (cold engine)
BMW E30 344i track car :banana:
BMW F31 335d xdrive
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jamesdark
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Post Sun Apr 09, 2006 9:37 am

I have done them to 0.25 when stone cold i left it over night and done them in the morning as for the right torque no idea, i haven't got a torque wrench i was doing them up pretty tight but i was worried about snapping them or overtightning so i did hold back a smidge, i'll get one today and do them again tomorrow to the right torque thanks for the suggestion. :cheers:
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Brianmoooore
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Post Sun Apr 09, 2006 2:55 pm

Obvious question is: Are you adjusting them further each time, or are they backing off?
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jamesdark
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Post Sun Apr 09, 2006 6:08 pm

When i re adjusted them last time i checked a few of them and they seemed ok still but i knew the noise was coming from them so i re-did them all from scratch which stopped the racket.
What do you mean by backing off?
Obvious question is: Are you adjusting them further each time, or are they backing off?
Demlotcrew
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Post Sun Apr 09, 2006 6:18 pm

Get a new spray bar in there as well as all other other things people will tell you to do.

Andrew
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jamesdark
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Post Sun Apr 09, 2006 7:40 pm

Will do,i take it they get clogged up etc,is bmw the best place to get one from or gsf/euro etc ok?
Get a new spray bar in there as well as all other other things people will tell you to do.
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Brianmoooore
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Post Sun Apr 09, 2006 8:47 pm

backing off?
= are the eccentrics slipping back to where they were before you adjusted them?
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jamesdark
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Post Sun Apr 09, 2006 9:05 pm

are the eccentrics slipping back to where they were before you adjusted them?
Right with you,yes a couple of them had slipped back as after i had adjusted them all,all the little holes on top of the eccentrics were lined up in pretty much the same position but when i readjusted them a few had clearly moved a bit.
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Brianmoooore
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Post Sun Apr 09, 2006 9:17 pm

jamesdark wrote:
are the eccentrics slipping back to where they were before you adjusted them?
Right with you,yes a couple of them had slipped back as after i had adjusted them all,all the little holes on top of the eccentrics were lined up in pretty much the same position but when i readjusted them a few had clearly moved a bit.
In that case it seems likely that you aren't tightening the nuts enough.
One other possibility I can think of - You can get the correct adjustment at two different positions of the eccentric as you turn it. Wonder if the wrong one would put extra load onto the adjuster and force it back. Wouldn't think the hole for the rod that you adjust them with would be in an accessable place in the wrong position though.
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jamesdark
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Post Sun Apr 09, 2006 10:38 pm

In that case it seems likely that you aren't tightening the nuts enough.
One other possibility I can think of - You can get the correct adjustment at two different positions of the eccentric as you turn it. Wonder if the wrong one would put extra load onto the adjuster and force it back. Wouldn't think the hole for the rod that you adjust them with would be in an accessable place in the wrong position though.
Not tightening them enough seems to be the most likely.
I did notice when adjusting them that i could go to far and they flipped the other way a bit but not far as i used a fairly long allen key,and the instructions in the how to i found in the articles section was pretty clear about everything i just don't remember it mentioning the torque setting for doing them back up.
I'll re do them tuesday and make sure they are all torqued up,so thank you for your advice and thank you also to charlE30 and Demlotcrew you've all been a great help and probably saved me from going insane.
Since i have got this car i'm getting a bit over sensitive to any ticking noises :teehee: