OK, Cosmo, here goes- - - -
I learned this method from my father, who ran a very successful auto shop in the 40's, 50's, and early 60's, and then spent the next 25 years teaching auto mechanics. He's 84 now, and still doing state-of-the-art work!
Since all 4-stroke engines with an even number of cylinders have two pistons that come to the top of the stroke at the same time ("companion cylinders") it's possible to watch the action of the valves and tell exactly when a cylinder reaches top dead center. For instance, on your 292, the #1 and #6 cylinders reach the top together, but while #1 is on the compression stroke with both valves closed, ready to fire the spark plug, #6 is between exhaust and intake, one full turn out of phase with #1. Here's the trick:
When a cylinder is between exhaust and intake, the exhaust valve will be closing, and the intake will be opening. That's called "overlap", or "rocking". By watching the valves in the overlap position, we can be sure the companion cylinder is exactly on TDC compression- - - -exactly where it needs to be for an accurate valve adjustment! Here's the drill- - - -turn the engine in the normal direction of rotation (clockwise from the front) until the #6 valves are rocking (exhaust closing, intake opening), then loosen both #1 valve adjustments until there's a little slack. This allows the hydraulic lifter to top out fully, something it can never do if the engine is running. Then carefully tighten the adjustment to barely take out the slack. Then turn the nut another 3/4 turn, and the valve is adjusted! Do the same thing for the opther valve on that cylinder- - -back off, take out the clearance, and adjust.
If you turn the engine exactly one turn, now #1 is on overlap, and you can adjust #6. There are three sets of companion cylinders, 1&6, 2&5, and 3&4. Here's an easy way to identify them. The firing order is 1-5-3-6-2-4, so just cut it in half and put the last half under the first:
1-5-3
6-2-4
The companion cylinders are above each other. If you get a cylinder rocking, the next one in the firing order will rock exactly 1/3 of a turn later. You can adjust all 6 cylinders in 2 turns of the engine, no oil splash, no noise, and completely accurate! Try it!
BTW, this method also works for solid lifters, just set the lash instead of preloading the hydraulic lifter.
Oregoon, you've got an IM with the same information!
Thanks for the kind words!
Jerry
