How do you free up a locked Honda engine?

To free up a locked Honda engine, start by removing the spark plugs to relieve compression. Then, apply a penetrating oil, such as PB Blaster or WD-40, into the cylinders and let it sit for several hours or overnight. Afterward, attempt to turn the crankshaft manually using a socket and ratchet on the crankshaft pulley bolt. If the engine still doesn't budge, you may need to repeat the process or consult a professional for further assistance.