Ford 1S7Z-6K254-AA Timing Belt Tensioner

The timing system is complex, and severe engine damage can occur if mistakes are made, so only highly experienced individuals should attempt this procedure. Begin by applying the parking brake and carefully jacking up the front of the vehicle, supporting it on jackstands. Remove the engine front cover, then carefully compress the timing chain tensioner and insert a pin to hold it in the compressed position, ensuring only the round plunger is compressed and not the ratchet mechanism. If the ratchet needs resetting, remove the tensioner, relieve the tension with a pick-type tool, move the ratchet back into the tensioner, and install a pin to keep it compressed. Next, remove the two tensioner mounting bolts and the tensioner itself, followed by the loose timing chain guide and the timing chain. If necessary, the left chain guide and camshaft sprockets can be removed. Before starting the engine, rotate the crankshaft by hand through at least two full revolutions, checking for any resistance that may indicate a problem. Remove the camshaft alignment tool if installed, loosen the camshaft sprocket bolts without removing them, and hold the camshaft with a wrench while doing so. Install the left chain guide if it was removed, followed by the timing chain and the right chain guide. Install the timing chain tensioner, tighten the fasteners, and remove the pin to release the tensioner. Reinstall the camshaft alignment tool and torque the camshaft sprocket bolts while holding the camshafts in place with a wrench, ensuring not to rely solely on the alignment tool. Finally, the engine front cover can be installed.