The 1989 Toyota pickup truck features a 3.0L V6 engine, which is a freewheeling engine. This means that should the timing belt stretch past the scope of the tensioner, the valves will most likely not hit the pistons and will probably not cause extensive engine damage, but it will leave you stranded. Toyota has not recommended a specific interval to change the timing belt, but previous use and service history suggests replacing the belt every 60,000 miles. It takes about five hours to replace the timing belt and no special tools are required.
Disconnect the negative battery cable and lay it aside, using a wrench. Do not let it touch metal. Place the drain pan under the radiator drain bolt, then loosen the bolt to allow the radiator to drain. If the drain pan is clean, the antifreeze can be reused. Remove the radiator, water outlet and its studs and the cooling fan, using the appropriate sockets.
Unbolt the power steering pump. Do not take the hoses off. Lay the pump out of the way. Loosen the clamps on the air intake hoses using a screwdriver or the appropriate socket. Remove the air intake hoses. Loosen the tensioners on the accessory drive belts. If the tensioner is a slider, loosen the bolt, then push the accessory toward the engine. If the tensioner has a pulley, use a wrench or socket to push the pulley away from the belt to loosen the tension on the belt. Lift the belts off the pulleys.
Remove the upper timing belt cover using the appropriate sockets. Turn the crankshaft clockwise until the notch on the crankshaft pulley lines up with the zero-mark on the lower timing belt cover. Check the camshaft sprocket timing marks. The left camshaft (as you are looking down at the engine) sprocket has a line that matches up with a line on the head at the 12 o’clock position. The right camshaft sprocket has three lines. The middle line lines up with the line on the head at the 12 o’clock position. If the camshaft timing marks are not lined up, turn the crankshaft one more turn, and all three marks will line up.
Remove the crankshaft pulley bolt using the appropriate socket, then, using the puller, pull the crankshaft sprocket off. Remove the fan pulley bracket and the lower timing belt cover using the appropriate sockets, then pull the timing belt washer off.
Unhook and remove the tensioner spring. Loosen the tensioner bolt. Push the tensioner out of the way. Tighten the tensioner bolt enough to hold the tensioner out of the way. Lift the timing belt off the sprockets and pulleys. Remove the tensioner. Check the tensioner by spinning it in your hand. If you hear noise or feel resistance, replace the tensioner. Measure the spring. If the length of the spring is not 2.21 inches, replace the spring. Reinstall the tensioner pulley and spring.
Push the tensioner to the left and tighten the bolt to hold it in place. Number the camshafts: the left one (as you are looking down at the engine) is C1, and the right one is C2. Remove the bolts from the sprockets, but do not remove the sprockets. Pull the dowel pins out of the sprockets. Do not turn the sprockets. The dowel pin holes must remain at the 12 o’clock position.
Reinstall the camshaft sprocket bolts, but do not let the heads of the bolts touch the sprockets. The sprockets should be able to turn freely. Make sure the timing marks are lined up.
Install the timing belt, starting on C1. Route it under the guide pulley that is between C1 and C2, then over the top of C2. Moving back to the left, route the timing belt behind the tensioner pulley, then on the right, behind the water pump pulley. Slide the belt under the crankshaft sprocket. Keep the timing belt taut on the non-tensioned side (the side with the water pump pulley).
Install the crankshaft pulley bolt temporarily. Loosen the tensioner bolt so that the tensioner puts tension on the belt. Turn the crankshaft clockwise two turns until the timing marks line up again. Tighten the tensioner bolt to 27 foot-pounds of torque. Remove the bolts from the camshaft sprockets. Insert the dowel pins, taking care that the camshaft sprockets do not detach from the camshafts.
Reinstall the camshaft sprocket bolts. Tighten the bolts to 80 foot-pounds of torque. Remove the crankshaft pulley bolt. Slide the guide washer on the crankshaft. Install the lower timing belt cover and the crankshaft pulley. Reinstall the crankshaft pulley bolt. Tighten it to 181 foot-pounds of torque. Install the rest of the parts in reverse order of removal. Tighten the radiator drain plug. Refill the radiator.
