My radiator on my 86 mazda keeps loosing water

Well, check the hoses first...do you see anything wet around the clamps or ends of either of the hoses? If not then look at the radiator cap...is there fluid around it? Look at the overflow bottle that is near the radiator...is it cracked? Finally look straight down at the radiator from above the cap...do you see fluid on ANY part of the radiator? especially down at the bottom of it? Look around the engine bay, do you see splatter marks from fluid hitting the fan? If you see fluid anywhere on the radiator itself fill the radiator back up and run the truck until it gets hot and see if you can spot the leaks. If however, there aren't any obvious leaks at all up front...go look at the heater lines that run into the firewall...if they have any leaks then you've found your solution. Another place to check would be around the water pump...just get a flashlight and look for fluid near the pulley that goes to the water pump. Good Luck