How do you replace the water pump on a 1991 Mitsubishi Eclipse 1.8L?

its behind the plastic timing belt guards. if your car is at or near 90,000 miles especially on an eclipse you need to get the timing belt changed anyway. if you are not a strong mechanic you probably shouldn't try this yourself. usually whatever shop you bring it to (if they're straight up) will change the water pump for no charge if you buy the pump from them. you can buy it yourself and they will charge you a little bit of labor so compare the two and go for the best. having said that and you are still determined to do it yourself buy a good repair manual for your car and get ready for some fun.