Toyota engines use silicone instead of gaskets on most of the accessories that are attached to the engine block, this re-manufactured water pump came with a new gasket.
Due to the imperfections on the water pump mounting surface we applied a light coat of silicone to the pump as shown in the image and we opted to use the gasket also, once the gasket was attached to the water pump we applied a light coat of silicone on the gasket prior to installing the water pump on the engine to ensure a proper seal with the engine block and to avoid coolant leaks.
Install a new thermostat and proceed to install the thermostat water outlet back on.
Make sure that the water outlet mounting surface is clean and that a new seal has been installed on the thermostat.
Remove timing belt idler backing plate mounting bolts and remove the plate from the engine to gain access to the timing belt idler mounting bolts.
Remove the 4 timing belt idler assembly mounting bolts and remove the idler/water outlet assembly from the engine.
Scrape the old silicone off from the intake manifold using a scraper.
If you are reusing the tensioner spring measure its free length, it should be 2.21 inches, replace if necessary. ( We installed a new spring because the old spring had rust on its surface )
Temporarily install the crankshaft pulley bolt to use it to turn the engine, turn the crankshaft 2 turns clockwise until the no. 1 cylinder is on TDC compression stroke, check all the timing marks making sure that they are properly aligned.( tensioner bolt needs to be slightly loose during this procedure to allow it to operate).
Make sure that there is proper tension on the belt prior to tightening the tensioner bolt, sometimes the tension on the valve springs cause the cams to rotate, to ensure that the timing belt remains tight use a wrench on the crankshaft bolt to maintain slight pressure in a clockwise direction, tighten the timing belt tensioner bolt to 27 ft. lbs.
Once the timing belt has been installed and the tensioner has been torqued correctly, remove the crankshaft bolt and install the timing belt guide washer, install the remaining items in the reverse order they were removed.
Refill the cooling system with coolant and start the engine, listen for unusual sounds, if you hear anything out of the ordinary stop the engine immediately and find out what caused it, if the engine sounds normal keep it running paying close attention to the engine temperature gauge, since most of the coolant was drained from the engine during this job, it is possible to have air pockets in the cooling system that could avoid the thermostat from operating properly, if the engine temperature rises above normal stop the engine, allow it to cool down and add coolant if needed, start the engine back on and repeat these steps until the temperature remains normal.
Once the engine remains at normal operating temperature set the engine timing using a timing light following the instructions on the label found under the hood, if you don't have access to a timing light it is recommended to take your truck to a repair facility and have them set the ignition timing correctly.