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Old 09-06-2001, 11:04 PM
Carrameow Carrameow is offline
Coming back from burnout
Join Date: Jun 1999
Location: in the Pacific Northwest
Posts: 2,274
Help. Setting Valve Clearances always did confuse me....

The 1985 300D Service CD tells you to set the Exhaust valve clearances to .35 mm and your Intake valve clearances to .10 mm. It also tells you to set the clearances when the Cam shaft/Rocker Arm relationship is as shown in the bottom right of the Diagram.
Which of my following reasoning/logic/assumptions is wrong?Something really confused me this afternoon.
(1) When the Camshaft and Rocker arm are as positioned in the Diagram, the valve is fully closed. That is because at this position the Camshaft places the least pressure on the Exhaust valve and allows the Spring to expand, closing the valve fully.
(2) Therefore you can use the Table to set the camshaft very accurately. For the top engine listed, for instance, when you are at 19 degrees before Top Dead Center, the Exhaust Valve should be fully shut and the Rocker/cam relationship should be as in the figure below.
(3) You must set the valves sequentially from front to back as you spin the crank clockwise and you must do this in a precise sequence of Crankshaft spinning.. If you over spin the crank and pass TDC by accident, and you are on the Fourth Intake valve, you must start all over from Valve One. You are not allowed to rotate one more revolution to get back to 13.5 degrees BTDC.

My assumptions are (1) Just go by the Diagram
(2) You will never get the rocker arm/camshaft relationship shown in Diagram (assuming it shows Valve fully shut) by using this table. Please disregard the Table.
(3) You can skip TDC as many time as you want. You can even jump from valve 1 to Valve 3 to Valve 5 back to valve 2 when you work on them, it makes no difference as long as if you have the Diagram's rocker/cam relationship.
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