Everyone has their own ways but what
@#41 said is one of the most popular ways. That said...
There are several ways and they all pretty much work the same. I knew my engine was well oiled when it ran and was kept in a garage for the 30 years it sat. I was fairly confident I could get it to turn by hand by going the oil route instead of the WD40 or another popular way, trans fluid. If oil or WD40 don't work, like
@#41 said, it's gonna get more involved.
I basically squirt a solid shot glass worth of 10W30 in each cylinder (a good 1.5 ounces or half+ of a bathroom dixie cup) and then let it sit for 24 hours. I used a bottle from a dollar store (yellow bottle has oil, red has gas) that I filled with oil and squeezed on about 18" or so of fish tank air tubing so that I could feed the end into each cylinder and squirt in some oil. I also pulled the valve covers and drizzled some oil on the rockers and on the push rods and valve springs/valves. After 24 or so hours, I cranked it by hand on the crank pulley bolt. Once it turns, with the valve covers off, you can also make sure all of the valves are moving up and down and you should be able to spin each pushrod around at some point in the engine cranking when the rocker arm isn't pushing on it.
You'll probably need to remove the fan shroud and possibly the fan if you still need more room for the breaker bar/rachet.
Good luck and ask away!
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