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beetos
07-13-2007, 08:34 AM
When setting valve clearances, does anyone know if there is an equivalent measurement between the cam and rocker versus the valve and eccentric? The rockers are unequal so the clearance between the cam and rocker versus the valve and eccentric will be slightly different, was wondering if anyone knew if you could set clearances by measuring at the cam instead of the eccentric.

bones
07-15-2007, 04:42 PM
beetos,this is a great questio and hopefully some of the engine gurus will respond.i just did a valve adjustment on my 2.5 and its not easy to be accurate between the lobe and rocker cause of space issues.sure would be more accurate to measure between eccentric and valve stem. bones

gale
07-15-2007, 06:10 PM
I had read the spec many years ago but forgot where. Simple enough to reverse engineer: Adjust it at 0.012" at the rocker tip and see what the largest size feeler guage will slide in at the cam lobe. Set a few of them at that size at the lobe and see if it still slides a .012 at the valve tip. One thing to consider: since they are probably 1.5:1 +/- rockers, the error will magnify at by that much at the valve tip when making the adjustment measurement at the lobe.

Bin_jammin
07-16-2007, 11:52 AM
You mean that's not where you're supposed to make the adjustment?

TC535i
07-16-2007, 04:18 PM
Why no room? I've always used angled feeler gauges in my 535i, would that help in your case? Just take the size you want off and bend it 90 degrees maybe?

Karl
07-16-2007, 08:08 PM
Gale has a good point -- because of the multiplication of the rocker arm, any measurement error you make at the cam end will be multiplied. I'll stick with measuring at the valve end.

bones
07-16-2007, 10:06 PM
karl,so you have allways measured 12ks at the excentric on top of the valve ?