The amount of labor hours that it takes for an engine replacement is between 10 to 15 hours.
In most cases an engine replacement in a vehicle takes between 10 hours to 12 hours in a professional auto shop but if you do it yourself it can take a few days or so.
In more complex engine replacements it may take as long as 15 to 20 hours to replace the engine.
Replacing the engine involves disconnecting hoses, wires, moving things out of the way, undoing motor mounts and a whole lot more involved.
Some vehicles such as rear wheel drive vehicles are easier in replacing the engine than front wheel drive vehicles.
Pulling an engine out of a rear wheel drive vehicle is often easier and in most cases you can pull the engine and transmission out at one time and then remove the bolts to the transmission easier.
Then you can mount the new engine to the transmission easier with the engine and transmission out and then place it all back in.
With front wheel drive vehicles you often need to remove the engine and transmission and entire frame underneath the vehicle along with the wheels and then work on it after all that is removed and then reinstall that back in together.
The cost for an auto repair shop to replace the engine can cost as much as $500.00 to $1,000.00 or more for the labor alone.
Replacing an engine is a big job.