How difficult is it to turn an engine by hand?

krazykuda said
Yes. Try mixing a rod cap or two and torquing them. If there is any misalignment with the bores, I've seen cases where one wrong rod cap can lock up the crank from turning.

If you do try mixing the rod caps, make sure you mark them so you can put them back on the correct rod. I would do that on an old engine, not the one you are going to run. Try not to keep tightening the rod caps, as they stretch slightly every time you torque them. Eventually they can stretch too much and break....

All my rod caps were numbered, half the number on the rod and the other half on the rod cap, so when put together correctly the number is easy to see. And I don't really have an engine lying around to try that.

But I just used a torque wrench, I know it's not really that accurate, just good to get a general idea I guess. With the spark plugs in it took about 78 food pounds once moving and with the plugs out it took about 33 foot pounds once moving. But that was using a torque wrench that is about 5 pounds lower than the setting at lower numbers, so the 33 is more like high twenties, the 78 should be pretty accurate though. I couldn't find an adapter to use a smaller torque wrench so I had to use the big one. Those numbers seem pretty good to me. Nothing crazy.