The man who told you this must have been the mechanic on the ARK! DUH!
That idea is about as old as Methusala.
It can be done and it will work but it will work sorta like the windshield wiper on a billy goats back end. Not very good!With the engine standing still, remove the spark plugs, turn the engine by hand until the #1 piston is at top dead center. Loosen the locking nuts on each and every valve. Mark the front pulley with a white out pen and on the block mark another place in line with the one on the pulley. Directly across the pulley at 180 degrees from the first mark, mark the pulley again. Mark the first mark so you can distinguish it from the second mark. Loosen the adjusting nuts on the valves of the #1 cylinder. With a mallett or a small ball peen hammer lightly strike the end of the rocker arm over the top of the valves. Do this on the adjusting side of the rocker arm too. Strike the top of the adjuster screw. (lightly!)This is called staking the valves. This will dislodge any foriegn materials that are under the valve seat and the valve drive train. Useing a feeler gauge turn the adjusting screw in until you can feel the feeler gauge begin to slightly hard to move back and forth between the top of the valve stem and the rocker arm. Tighten the locking nut taking care not to move the adjusing screw. Do this on both valves on the #1 cylinder. Next turn the engine clockwise from the front until the second mark you made on the front pulley is aligned with the one you made on the engine block. Stake and then adjust the cylinder that is next in the firing order for this engine
which is #2 &1-2-4-3 When you get that #2 adjusted then go to the next in firing order #4 and do the same after you have moved the pulley back to the point where you started. Move the pulley one more time to the second mark and do the last #3 cylinder and you have them adjusted. Put the valve cover on and button up everything and crank it up. You can make a temporary gas tank from a lawn mower tank etc and run a rubber line to the carb inlet to try it out if you are not confident in what you have done. You can even start and run it for a while with the valve cover still off and then recheck your adjustments if you prefer. However if you follow these instructions it is unlikely you will have to readjust. Remember too that a couple of thousands on this engine will not matter cause any adverse effects in it's operation one way or the other.
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