Factors affecting the time include:
* Mechanic's experience: A seasoned mechanic will be faster.
* Availability of parts: Delays in getting parts can significantly add to the time.
* Condition of the engine: Rust, seized bolts, or other complications can prolong the repair.
* Access to tools and equipment: Proper tools and a hoist make the job considerably faster and easier.
Attempting this yourself without significant experience is strongly discouraged. It's a complex repair requiring specialized tools and knowledge. The risk of damaging the engine further is substantial. The cost savings of DIY might be offset by costly mistakes.