3.0 tappet question

if you look at the blue manuals, it says, 0,25 to 0,3 mm for a cold engine
my experience is that it is very difficult to get any of those values when you are doing this, so what i ended up doinng is this:
i use the 0,25 for setup, and i assure a loose insertion of this one, then i check that the 0,3 is not able to pass through the gap, the result is that i am somewhere in the middle of these two values
it works ok
 
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I seem to remember the service interval is about 8,000 mi/10,000 km between adjustments. How critical is this timing? For a well broken in motor, how much adjustment is usually necessary? One or two valves? All of them? And how much?

I ask because mine is due for a valve check but I've got two projects in the shop ahead of the Coupe. Am I risking burned valves? It's currently pretty quiet, don't know if that's a good thing or not.
 
mr bump said:
Its quiet down the tappets day tomorrow, whats the gap settings for inlet and.outlet?
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Re: maintenance intervals? Common sense applies. If you constantly peg the tach to redline you are more apt to stretch and wear things. A garage queen is less likely to need adjustments, but its hard to say that routine valve lash checks is ever a bad idea. The factory service interval recommendations are a balance of the absolute need for maintenance versus a "relatively" reliable and "trouble-free" product. Just like oil changes, if you value the car, severe service typically involves increased service intervals.

Valves that are too tight can no doubt lead to problems yet there is a fair bit of built-in latitude for the vast majority of M30 plants. Agree with Steve (who doesn't?) too quiet and you are pushing the envelope or adding the 90 weight in the wrong orifice. A happy engine's valve train typically sounds like a well oiled sewing machine. The exception might be DQ's handiwork which the factory might have a hard time duplicating! :smile:

hth



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valve adjustment

Hi,

We would always set valves at 12 thou across the board at the dealership, on automatics, we would set them on the loosser side of 12 thous , almost to 13 thous. This allowed the engine to breath better when the auto was engaged. we all know how much of a load those old auto trans put on an engine when they were engaged

BMW engines should sound like a quiet sewing machine, just a little valve sound, nothing heard will damage valves after a long enough time running tight.

Thanks, Rick
 
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