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Anybody use the clean-wood-dowel-rod-in-the-spark-plug-hole trick for determining top dead center for each cylinder? (Works great on BMW motorcycles, as long as cleanliness is strictly observed.)
How about bumping the starter motor with the ignition key to turn the engine?
How about using the 32mm fan/water pump nut and belt tension to turn the engine to the next setting?
Any thoughts on insight into these or similar tips & tricks will be much appreciated.
opinions will vary and be debated adnasseum on this subject. Will provide my method.
Don't pull the plugs...no need. I wouldn't make a practice of using the dowel technique due to cleanliness issues anyway. I also don't use a bump starter button to nudge the crank around....I turn it manually CW with a 36mm socket and 1/2 drive rachet right from up top on the passenger side. Turning the alternator will likely slip the belt without leaning on the belt...cumbersome.
Get a sheet of paper and make 2 X 6 circles denoting 6 exhaust and 6 intake valves.
Start where the engine is in its present state with the valve cover off...no need to put it on no. 1. Inspect all the lobes to see where they are. Select the first one that is pointing straight toward the crank centerline..not toward the ground...the engine is layed over 30 degrees. Set that valve...I set mine to a slip .013" cold. Check the circle on the paper. Move to the next valve that is closest to having its cam lobe down toward the crank...etc, etc. Rotate the crank CW (looking from the front) as need be...it goes quickly.
HTH,
George
P.S. For those out there...check your valves. I am meticulous about this but almost invariably find one that is out. This time no. 6 intake valve was a bit tight. Checked mine last week with the valve cover off for repaint. Gonna safety wire my banjo bolts this time as per usual the new bolts with encapsulated loctite I just installed 4K ago were below torque spec and am not going to deal with this again.
But, look at me now! Friday night I did my third valve adjustment, and it went so much easier and smoother than before. Why? First of all, I didn't use the ridiculous order of adjustment called out by Bentley (for whatever reason, I can't imagine.). I just did it like George said.- I opened it and found the cam lobes pointing toward the engine. But before I started, I made a rough drawing on a piece of paper, showing the position of all 12 valves. Upon completing each one, I checked it off. When I needed to rotate the camshaft, I just sat in the car and blipped the throttle. (I had made a nice liitle pushbutton setup to blip the starter from the diagnostic port, but this did not work on this particular car- my E30.) I finally solved the dilema of how loose or tight the feeler guage should FEEL for an accurate setting by using my NSK micrometer to measure my feeler guage. This way, I could judge just how tight it should feel when the reading was correct. (BTW, you would need to make it very tight, indeed, to sqeeze the feeler guage down an extra .001.)
Put it back together and it runs and sounds PERFECT.
Quote:
Originally Posted by George M
:p
To turn the engine I use thinned 1-1/4" wrench on water pump while applying thumb pressure on fan belt. Removing the plugs makes it easier…but not essential.
To find TDC I use the firing order 153624, recognizing that when one cylinder is at TDC on compression stroke, there is another cylinder at TDC on exhaust stroke.
When cylinder 1 is at TDC (compression), valves on cylinder 6 are "rocking" (TDC exhaust). That is turning engine one direction opens intake valve, turning the other direction opens the exhaust.
When cylinder 1 is at TDC, valves on cylinder 6 are "rocking" 153624
When cylinder 5 is at TDC, valves on cylinder 2 are "rocking" 153624
When cylinder 3 is at TDC, valves on cylinder 4 are "rocking" 153624
When cylinder 6 is at TDC, valves on cylinder 1 are "rocking" 153624
When cylinder 2 is at TDC, valves on cylinder 5 are "rocking" 153624
When cylinder 4 is at TDC, valves on cylinder 3 are "rocking" 153624
See the pattern?
With this method you can start anywhere by looking for the cylinder whose valves are closest to “rocking”
Paul Shovestul
Quote:
Originally Posted by Bart