When you are replacing a water pump on a vehicle, should you replace the timing belt on the vehicle as well?
This depends on the vehicle. On some cars, the water pump is driven by the timing belt. On these cars, you should always replace the timing belt and water pump at the same time. When you have the engine apart, the only additional cost is the actual cost of the part. The labor should be the same. On other cars, the water pump is driven by the serpentine or fan belt. The timing belt and the water pump are not related, so there is no rule that both should be replaced.
It depends on the make of the car. Some Hondas and Meesoshitties require replacement of the timing belt whenever it is removed due to stress factors and crap. So it is always a good idea to go ahead and do since on a lot of front wheel drive cars you will have everything off in front of the timing belt anyways. So might as well do it right? Better that than end up on the freeway with a snapped timing belt. Not fun.
if the water pump is driven by the timing belt then its a good idea to change both as the labor to get into water pump is the same as to do the timing belt. I'd spend the extra $50 for the belts and change them while I'm in there and that way you'll be ahead of the game instead of paying (or taking the time) to do it twice at two different times
Yes, if the timing belt drives the waterpump. A new belt would only cost another $50 or so when the engine is already stripped for work on the pump rather then many hundreds if you did it separately later on. If you live in a particularly humid (FL etc) or dry (NV etc) climate the belt may not last the manufacturers specified duration anyway and for the sake of a few bucks you can sleep safe in the knowledge that your engine is less likely to self destruct for the sake of a $10 piece of rubber. You should also have the other pulley bearings etc checked for wear and replace them if necessary.
No. However I think you may be confusing the timing belt with the fan belt. Typically the timing belt is located within the engine. Some european models require this belt replacement. Typically 75 to 90 thousand miles. The fan belt, which is the belt that you can see in the front or side of the engine does need replaced occasionally. However just because you are changing the water pump doesn't mean that either of these belts need replaced. If the fan belt has cracks in it, then yes I would go ahead and change the belt at the same time that you are having the water pump changed.
