Car Fix DIY Videos

http://clublexus.com/how-tos is the leading Lexus IS, RX, ES, and GS resource for technical DIY guides. Replacing the water pump in the Lexus IS is not too difficult and will ensure your engine runs cool. For the full step-by-step article, please visit http://www.clublexus.com/how-tos/a/lexus-is-how-to-replace-water-pump-362363

The water pump is designed to push coolant from the radiator into the engine block and over the heads to cool them down. It’s part of a system that prevents the car from overheating which could cause severe engine damage. Without it, fluid does not move and the engine will potentially seize. If your water pump fails, you need to replace it immediately; otherwise, you can change it at the manufacturer’s recommendation.

This moderately difficult to hard job takes four hours and costs around $250 to complete. The professional cost starts at $800.

This job requires a ⅜ inch ratchet, a ½ inch breaker bar, torque wrench, various socket wrenches, 5 and 10 millimeter Allen or hex wrenches, channel lock pliers, and a special pulley holder tool.

Step One – Remove the plastic engine covers

Pull off the plastic engine covers. The large plastic front cover is held in with 11 clips. It’s found on top of the radiator facing the front grille. Remove the V-bank cover sub assembly, which covers the main engine, centered under the hood. The scoop faces the front grille just over the radiator. There are only a couple of bolts that hold these parts together.

Step Two – Loosen the water pump bolts

Loosen the four bolts holding the water pump pulley in place before removing the serpentine belt. The tension from the belts will help keep the pulley in place while unbolting it. This can be done later if the special pulley holder tool is available, but it’s not necessary to do it this way.

Step Three – Remove the v-ribbed belt

Turn the bolt on the tensioner clockwise just enough to loosen the belt and remove it. Use a breaker bar and a 14 millimeter socket to get leverage.

Step Four – Remove the serpentine belt tensioner assembly

Finish removing the four bolts on the water pump pulley to remove it completely. Next, remove the belt tensioner pulley and the idler pulley. The tensioner pulley, circled in green, is left-hand threaded, so turn right to loosen. The other pulley, circled in red, is normal thread, so turn left to loosen.

Step Five – Drain the engine coolant

Attach ⅜ inch vinyl tubing to the petcock valve at the bottom of the radiator. You’ll need to twist the white nut to open the valve and drain the radiator coolant. Unscrew the radiator cap to help the coolant flow more smoothly.

Step Six – Remove the coolant reservoir

Remove the water reservoir by removing the two 10 millimeter bolts. Pull off the the two hoses connected to the cap as well.

Step Seven – Disconnect hoses from the water inlet

Disconnect the clamps holding the six hoses to the water inlet. Use pliers to relax the clamps holding them on.

Step Eight – Remove the water inlet

Disconnect the five hoses, four bolts, nut, and water inlet. Remove the water inlet housing gasket and water outlet pipe O-ring.

Step Nine – Remove the injector driver

Remove the three 10 millimeter bolts holding the injector driver and move it to the side. Unplugging the box is not necessary.

Step Ten – Remove the water pump assembly

Remove the 16 bolts, which are 12 millimeter, on the water pump. There are three different sized bolts securing the water pump, so work smart and keep the different bolt sizes together. Be prepared for a waterfall of coolant to flush out after removing the water pump. Get a bunch of rags ready and cover the floors and the pulleys.

Step Eleven – Install the new water pump

The bolts from the last step need to be re-installed. Torque the large bolts (A) to 15 feet pounds. Medium and short bolts (B and C) must be torqued to 6.5 feet pounds.

Step Twelve – Re-install various components

Be sure to replace the O-rings mentioned in Step 8 or else there will be leaky water pump problems. Torque the four bolts to 7 feet pounds.

Re-install the water pump pulley and the other two pulleys that were removed. Tightening them to their recommended specification of 15 feet pounds is difficult without the serpentine belt on. Tighten enough so that you can put the serpentine belt on, then tighten fully to specification.

Re-install the coolant reservoir and the remaining radiator hoses, and re-attach the plastic engine covers.

Step Thirteen – Finishing up

Refill the radiator with Toyota Super Long Life Coolant and let the car run until it’s warm. Check for leaks and continue adding through the radiator cap until the coolant level is correct. When finished, re-attach the plastic engine covers.