Guy above never really answered the question. So here goes..
No.. you do not need to change the water pump when changing the timing belt. You can, while you are in there. It saves you the cost of the labor, you only pay for the part that way.
Hope that helps!Do you really need to change the water pump when changing the timing belt?
Water pumps and there seals last quite along time with regular maintenance. Some times, the life or your vehicle! You water pump wont fail cause your changing the timing belt. I would just have it cleaned out and re-fitted to your car after the timing belt is done. No need to worry about it.
If it does fail (witch it shouldn't) your car would over heat as it would not be pumping the coolant through your engine block to keep it cool.
I'm not sure what the previous responder meant by proper maintenance on a water pump and gasket. Other than changing the coolant there is very little you can do the maintain a water pump. There are lubricants available but since it is a sealed bearing they are basically useless.
Most of your repair cost on a timing belt is labor, which will be repeated if you have to have the water pump done later. The days of lifetime water pumps are gone, and since you got 60K on this one I'd replace it and you should be fine for the next 60K. Remember, if it goes (and since it's buried you probably won't know until it fails completely) and you don't recognize it immediately; you'll be paying for a rebuilt engine. It's a great investment.
If you do a regular maintenance for the water pump it will work for many years in your car ,so you can skip it for now even if you will do an over all repair of your engine.
No. At 120k , it mignt be a worthwhle preventive idea, if it's one that takes a lot of labor to get at. A simple car w/o AC or PS, it's usually not that big a deal to get at as needed - when it starts to drip.
the gasket will last until it starts to leak thats when u need to change it