The water pump on the 1993 Toyota 1.6-liter engines is located on the front of the engine. It is not part of the timing belt, so just about anyone can change the water pump. The '93 Toyotas come with several different engines. The process here relates to the 4A-F and 4A-GE engines. You can find the engine identification on the sticker on the underside of the hood or on the radiator fan shroud. The identification is in the small square on the top left.
Place the drain pan under the radiator petcock. Open the petcock and allow the antifreeze to drain. If the drain pan is clean and the antifreeze is less than five years old, you can reuse the antifreeze.
Place the block of wood on the floor jack. Slide the jack under the engine and raise the engine slightly. Unbolt and remove the front engine mount. On the 4A-GE engine, loosen the power steering and air conditioning belts by loosening the adjusting nuts or bolts on the slider bracket and sliding the accessory toward the engine. Remove the belts.
Loosen the water pump pulley bolts with the appropriate socket. Loosen the alternator locking bolt and the pivot nut. Push the alternator toward the engine to loosen the tension on the belt. Lift the belt off the pulleys.
Remove the four bolts on the water pump pulley using the appropriate socket. Remove the water pump pulley. Disconnect the water inlet and bypass hoses from the inlet pipe using a screwdriver or pliers, depending on the type of clamp used.
Disconnect the water inlet pipe by removing the two clamp bolts and the two nuts behind the pump. Remove the inlet pipe. Remove the O-ring from the back of the pump. Remove the mounting bolt on the oil dipstick tube. Remove the tube and the dipstick. Plug the hole with a rag so that debris doesn't get into the crankcase and contaminate the oil.
Remove the upper and middle timing belt covers. Remove the water pump retaining bolts and pull the pump off the engine. Take care not to get any antifreeze on the timing belt.
Place the O-ring in its groove on the block. Install the water pump and tighten the bolts to 11 ft.-lbs. of torque. Reinstall the timing belt covers. Make sure they are seated properly and not touching the timing belt.
Coat a new oil dipstick O-ring with engine oil. Slide it on the dipstick. Reinstall the dipstick and the retaining bolt. Tighten the bolt to 82 in.-lbs. of torque. Place a new O-ring on the inlet pipe for the water pump. Reinstall the inlet pipe. Attach the clamps and bolts that hold the pipe in place. Tighten the bolts to 8 ft.-lbs. of torque.
Reconnect the inlet and bypass hoses to the pipe. Install the water pump pulley. Tighten the four pulley bolts enough to hold everything in place. Reinstall all the accessory drive belts and adjust the tension properly. You should be able to turn the belts 90 degrees when they are at the correct tension. The water pump should resist turning. Tighten the water pump pulley bolts to 17 ft.-lbs. of torque. Reinstall the engine mount. Tighten the petcock on the radiator. Refill the radiator.
