Jerry;
Does that trick hold true for all Stovebolt sixes or is that 216 specific.
That works on all engines with an even number of cylinders. If the firing order is split in half, and one group arranged under the other, it identifies "companion cylinders". For instance:
Inline six firing order (all makes) 1-5-3-6-2-4
Companion cylinders:
1-5-3
6-2-4
When the #1 cylinder is on compression with both valves closed and the spark plug ready to fire, the #6 exhaust valve is closing, and the intake valve is just beginning to open. This is known as "rocking". By watching the #6 valves, you can be sure #1 is in the firing position, ready for a spark. Ditto for 5 and 2, and 3 & 4.
Now let's try a small block V8: 1-8-4-3-6-5-7-2
Companion cylinders:
1-8-4-3
6-5-7-2
Once again, the 1 and 6 compression strokes are one full turn of the crankshaft apart. Watch the #6 valves, find their "rocking" position, and set the distributor to fire on #1.
An engine with an odd number of cylinders like an Audi or one of the newer GM inline 5's takes a little more effort: Get a cylinder's valves "rocking", mark the crankshaft position on the balancer, and make one full turn of the crank. You are now at top dead center on the compression stroke for that cylinder.
The same procedure works for adjusting valves.
Jerry
