DIY How To: M20 Valve Adjustment

M20/M30/M50/Whatever! All engine related stuff here.
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Re: DIY How To: M20 Valve Adjustment

Post by Aussie 325i » Thu Sep 12, 2013 11:59 am

Great, thanks
1988 Lachssilber E30 325i sedan.
Factory fit-out: manual; SILBER LEDER; M SPORT SUSPENSION.
Modifications so far: Miller MAF + 19# ECU; Ford 19# Design 3 injectors; IE adjustable FPR; KAMotors CF airbox; Innovate MTX-L; EBC Greenstuff pads.
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Re: DIY How To: M20 Valve Adjustment

Post by blasphemy101 » Thu Sep 12, 2013 6:01 pm

e21jps wrote:Here is a really usefull tip!
if the head is not new the method described can often still result in the wrong clearance, this is because the eccentric usually wears a little hollow in the tip of the valve stem, the feeler gauge bridges this hollow and holds the eccentric above it so you end up with a much bigger clearance that you think and the engine still ticks :cry:

So a better way is to put the feeler gauge between the cam and the follower BUT!!!! you must then account for the rocker ratio and the setting should be only 007" or 0.16mm

This will work every time no matter how worn the eccentrics are and you should have a nice quiet engine again 8)
This guy knows his stuff. Definitely going to do my adjustment this way once the engine is secured back to the car lol
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Re: DIY How To: M20 Valve Adjustment

Post by 87e30 » Tue Sep 24, 2013 1:30 am

Dontrusthise30 wrote:*Don't forget to remove the ratchet from the crankshaft bolt!!*
I forgot to remove the wrench from my crankshaft bolt... Good thing I was using an open end wrench and it just fell off when I cranked the engine lol.
Schwarz 5-speed 87 325is (newest project)
Arktisblau 5-speed 86 325e (current DD)
Schwarz 5-speed 87 325e (parts car/LS1 swap?)
Gazellenbeige automatic 85 318i (70,000 miles)
Alpine white 5-speed 87 325is (my first e30, possibly for sale)
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