The 5.4-liter engine found in the 2001 Ford F-150 truck is a dual overhead cam design. This means that there is a camshaft located in each cylinder head that opens and closes the valves. Two separate timing chains driven by the engine crankshaft operate the camshafts. When these timing chains or tensioners wear out, they must be replaced to prevent engine damage if they break or slip. This is a major engine repair that will take a highly skilled technician eight hours to complete.
Remove all drive belts and belt-driven accessories, including the fan and water pump. Remove any components that attach to the front engine covers or obstruct their removal. Remove the front engine timing chain covers.
Unbolt the two retaining bolts for the sensor ring on the crankshaft and remove it. Turn the engine over by hand to place the crankshaft keyway directly at the 12 o'clock position. This is the slot in the crankshaft with a square steel piece in it. Install and tighten the camshaft aligner tool on both camshafts. Do not allow the camshafts to turn separately from the crankshaft at any time. Remove the timing chain tensioners from both timing chains by removing the three bolts from the tensioners. Remove the timing chain tensioner arms.
Remove the right timing chain from the camshaft sprocket and then the crankshaft sprocket. Do the same for the left timing chain. Slide the crankshaft sprocket from the crankshaft and keyway. Install the crankshaft holder on the crankshaft. Remove the retaining bolts and remove both timing chain guides. Place the chain tensioner in a vise to compress the piston. Push into the hole at the top of the tensioner with a pick to push the ratchet arm into the housing. Insert a paper clip into the ratchet assembly to secure the plunger for installation and remove the tensioner from the vise.
The new timing chains should have two copper chain links at opposite ends to assist in timing the engine. If you can not see them, mark one link of the chain, and mark the link at the opposite end of the chain when it is doubled. Loosen the camshaft holding tools slightly to allow some movement of the camshafts. Rotate the left camshaft with the positioning tool until the timing mark on the sprocket is at the 12 o'clock position. Rotate the right camshaft until the sprocket index mark is at the 11 o'clock position. Tighten the camshaft holding tools to lock them into place.
Install the timing chain guides on each side of the engine. Remove the crankshaft holding tool and install the crankshaft sprocket. Face the flanges forward. Place the lower end of the inner chain on the crankshaft sprocket, aligning the timing mark on the outer flange with the copper or marked link on the chain. Do the same with the outer, or right side chain, being certain that the marked links line up with the timing marks. The other brass link or mark should line up with the timing mark on the camshaft pulley. You can use the camshaft positioning tool, if necessary, to adjust the camshaft sprocket slightly to align the marks. Take a minute to double-check the marks to be certain that they are in the right position.
Position the left-hand timing chain tensioner arm on the dowel pin on the engine block and install it. Place the other side on the right-hand side. Remove the retaining pin from both of the tensioners. Remove all of the special tools from the engine and place the crankshaft sensor ring on the crankshaft. Install the bolts retaining the ring. Install the front engine cover and all accessories.
