Lincoln XL1Z-6L266-AA Timing Chain Tensioner

It is very important not to rotate the crankshaft or camshafts after the timing chain(s) have been removed due to the possibility of harming the valves or pistons - special tools are required to lock the camshafts during removal. Start by using the number one cylinder with Top Dead Center and then pulling the spark plug and also taking out the negative cable from the battery. Next, the engine cooling fan should be removed as well as in certain models, the radiator should be taken off as well. Move on and remove the valve covers, drain the engine oil as well as take off the crankshaft pulley. Some models require also the removal of the water pump and its pulley, power steering pump, drivebelt tensioner, and idler pulleys. Remove camshaft and crankshaft position sensor connectors if necessary, and remove the air conditioning compressor without disconnecting refrigerant connections. Check all the connectors and brackets on the harnesses, and then undo the nuts and bolts that hold the timing cover and the cover away making sure that you do not use over torque. Take off the timing cover gasket and dowel pins, then timing chains between the crankshaft and the camshafts. For 1999 through 2004 two-valve engines, fit the camshaft and crankshaft retaining tools, to lock the camshafts at the TDC and protect them from being damaged. Take off the right and left timing chain tensioners and stationary guides, and if it is necessary - the camshaft sprockets. In 2005 and later three-valve models, the engine needs to be rotated to its proper position and the camshaft rocker arms should be removed in addition to making certain that the timing chain marks are easily seen before installing the timing chain guides and sprockets. For confirmation of its position, turn the crankshaft; next, remove dirt and grease on the joint surfaces; spread RTV sealant on the cover surfaces; grease the timing chains; bolt on the timing cover. Lastly replace the crankshaft front oil seal and continue with reversing the process put the right quantity of the engine oil and the coolant then start the engine to check for any possibilities of leaking.

These engines are very difficult to service and many tasks on them need specialised tools. It is therefore important that when working with timing chains, camshafts or when lifting the cylinder head it is very important to read the instructions and ensure that correct tools are used to avoid damaging the engine. The timing system is delicate, and if an error is made something really dreadful can happen to the engine; therefore, only experienced mechanics should handle such jobs, and if you are in doubt, seek advice from a specialist. Verify all tasks before commencement of the engine to avoid any form of incorrect working. Since this is an 'interference' engine design, a snapped chain damages the valves and, most likely, the pistons, which requires cylinder head extraction. First, remove the battery, take off the spark plugs and hold the number one cylinder at the Top Dead Center or TDC for short. It is followed by the elimination of valve covers and timing chain cover depending on the arrangement of timing chains in the 4.6L and 5.0L engines. For 4, 6L, you do not need the toothed wheel located in the crankshaft housing and position the crankshaft as described above, and then take off the rocker arms of the cylinders that are marked. Move on to the next step in order and uninstall the timing chain tensioners, and chains, and if need be, the camshafts. When working with 5.0L engine, a special tool needs to be used in order to rotate the crankshaft, compress the tensioners and properly and gently remove the primary timing chains and VCT assemblies so they would not be confused with one another. Inspect sprocket teeth, chains, and tensioners and replaced any that are found to be worn out or damaged. Whilst the installation for the 4.6L engine, accurately align the timing marks fitted the timing chain guides and tensioners then the rocker arms. In the course of the assembly of the 5.0L engine, make sure that the assembly marks in VCT match the secondary chains, fix the primary timing chains and ensure that all parts are well anchored. Last, turn the crankshaft to feel if there is any resistance and do it in the reverse method of its removal.

Remove the timing chain cover, the crankshaft position sensor toothed wheel, and install the appropriate camshaft holding tools.

The timing system is complex, and severe engine damage will occur if mistakes are made. Do not attempt this procedure unless you are highly experienced. If unsure, consult an expert. Double-check all work before attempting to start the engine.

Inspect the individual sprocket teeth and keyways for wear and damage, check the chain for cracked plates, and replace any worn or defective parts.

The camshaft(s) must be retained exactly at TDC; if the valve timing is off when the timing chain(s) are reinstalled, severe engine damage could result.

Carefully rotate the crankshaft by hand through at least two full revolutions. If you feel any resistance, stop and find the problem before proceeding.