A professional mechanic might complete the job in 2-4 hours. This includes things like diagnosis, parts procurement (if needed), and cleanup.
For a reasonably experienced DIYer with the right tools, a realistic estimate would be 4-8 hours, or even longer for a first-timer. This longer timeframe accounts for potential unforeseen difficulties, like rusted bolts or unexpected complications.
Factors that can significantly increase the time:
* Rust and seized bolts: Older vehicles are prone to this, requiring extra time for penetrating oil, heat, and careful removal to avoid damage.
* Lack of proper tools: Having the correct sockets, wrenches, and possibly specialized tools for the job will save considerable time.
* Unexpected issues: Finding other worn or damaged parts during the process will add time to the repair.
* Unfamiliarity with the process: The first time you tackle this, it will inevitably take longer than subsequent attempts.
Before starting, consult a repair manual specific to your vehicle's year and model. This will provide detailed instructions and diagrams, significantly reducing the time and potential for mistakes. Remember safety first – disconnect the battery before working on the cooling system.