GM 24506090
Timing Chain

During Timing Chain and sprocket replacement start by taking out the engine front cover first. Use the Crankshaft to rotate until the timing marks reach alignment with each other: the Timing Chain dampener should align to the Crankshaft and camshaft sprocket hole positions. You should align the Timing Chain dampener to Crankshaft sprocket placement and Timing Chain dampener to camshaft sprocket locator hole location. The next step is to remove the camshaft sprocket bolt as well as the camshaft sprocket with its attached Timing Chain. Operation of the Crankshaft gear remover (J 5825-A) extracts the Crankshaft sprocket prior to cleaning the Timing Chain dampener bolts and removing the Timing Chain dampener. Start by removing the camshaft thrust plate bolts afterwards remove the camshaft thrust plate. The Timing Chain and all its gears should undergo cleaning and inspection before building the mechanism. Position the camshaft thrust plate followed by its bolts then tighten both components to 10 nm (89 inch lbs.). The Crankshaft sprocket installer (J 38612) helps place the Crankshaft sprocket and is removed afterward. Use engine oil supplement gm p/n 1052367 and canadian p/n 992869 or equal product for application to the sprocket thrust surface. Secure the Timing Chain dampener to the block through bolt torques of 21 nm (15 ft. Lbs.). Secure the camshaft sprocket by holding it up with the chain facing downward while you position the chain to the Crankshaft gear. Keep the Crankshaft timing mark lined up with the bottom of the Timing Chain dampener marking. The camshaft gear installation requires its timing mark to match the mark located on top of the Timing Chain dampener. Use the mounting bolt to place the camshaft sprocket onto its position then tighten the bolt to 140 nm (103 ft. Lbs.). Place a thin coat of engine oil on both the Crankshaft and camshaft sprocket before reinstalling the engine front cover.

The first step to change timing components involves removing the engine front cover. Begin the installation by having the crankshaft timing mark match the timing mark on the bottom of the Timing Chain Tensioner while the Camshaft gear timing mark lines up with the timing mark on top of the Timing Chain Tensioner . Following the removal of the Camshaft sprocket bolts proceed to take out the Timing Chain and then the Camshaft followed by the crankshaft sprockets. After extracting the Timing Chain Tensioner bolts you must also take out the tensioner unit. Remove the Camshaft position actuator filter which rests at the Camshaft's end. The Camshaft requires a brand-new Camshaft position actuator filter during installation at its ending point. Mount the crankshaft sprocket onto its installation surface before applying prelube to the sprocket's thrust region. Finally, position the Timing Chain Tensioner before bolting it into place at 21 n.m (15 lb ft). The en-47719 tensioner compressor (EN-47719) helps fully collapse the tensioner before inserting the tensioner retaining pin into its designated hole. Position the crankshaft timing mark exactly where it matches the bottom timing mark feature of the Timing Chain Tensioner. Position the Camshaft sprocket with Timing Chain dangling while you install the Timing Chain onto the crankshaft gear. Position the Camshaft gear timing mark directly above the timing mark located on top of the Timing Chain Tensioner and ensure both the dowel in the Camshaft sprocket lines up with the dowel hole on the Camshaft. The mounting bolts should be tightened to 16 n.m (12 lb ft) while drawing the Camshaft sprocket onto its position on the Camshaft. After removing the Timing Chain Tensioner retaining pin activate it by applying clean engine oil to both crankshaft and Camshaft sprockets before installing the engine front cover.

The crankshaft sprocket installer (J33612) serves to install the crankshaft sprocket ahead of the Timing Chain service or repair procedure. First apply prelube gm p/n 1052365 or an equivalent to the crankshaft sprocket thrust surface before installing the Timing Chain dampener with its bolts. Tighten the Timing Chain dampener bolt to 21 nm (15 ft. Lbs.). The crankshaft timing mark needs to be lined up with the timing mark on the bottom face of the Timing Chain dampener. Fit the camshaft sprocket to the crankshaft by suspending its Timing Chain downward so you can install the Timing Chain to the gear. Line up the camshaft gear timing mark against the timing mark on top of the Timing Chain dampener making sure the camshaft dowel fits into the camshaft sprocket's threaded hole. After positioning the camshaft sprocket onto its camshaft through the mounting bolt apply engine oil to the crankshaft and camshaft sprocket components before tightening the bolt to 140 nm (103 ft. Lbs.).

Start your replacement process of Timing Chain and sprockets by taking off the engine front cover. Use your tools to rotate the Crankshaft until the timing marks show direct alignment. Set the camshaft alignment pin and the Timing Chain dampener exactly at the Crankshaft sprocket position. First remove the sprocket bolt from the camshaft before taking out the camshaft sprocket with the chain attached then extract the Crankshaft sprocket. Begin by taking out the bolts from the Timing Chain dampener before extracting the dampener itself. Remove the camshaft thrust plate bolts from the assembly and remove the thrust plate when needed. The technician needs to clean and evaluate the Timing Chain as well as its gears. Put the camshaft thrust plate into position then torque the bolts to 10 nm (89 inch lbf). First apply engine oil supplement gm p/n 1052367 (which equals Canadian P/N 992869) or equivalent to the sprocket thrust surface before placing the Crankshaft sprocket in position. Tighten the Timing Chain dampener bolts to 21 nm (15 ft. Lbs.) during installation. First install the Timing Chain into position onto the camshaft gear and use the camshaft sprocket to hold the chain as you position it toward the Crankshaft Gear. Position the Crankshaft timing mark to match the timing mark on the bottom of the Timing Chain dampener while you align the timing mark on the camshaft gear to the center line of the locator hole and that mark to the timing mark on the top of the chain dampener. Place the dowel into the camshaft's dowel hole before pulling the camshaft sprocket onto the component by driving the mounting bolt. Install the camshaft sprocket bolt with a torque setting of 140 nm (103 ft. Lbs.). After treating each part with engine oil you should replace the engine front cover.

Begin the replacement work by removing the engine front cover. Position the crankshaft timing mark to match the timing mark below the Timing Chain Tensioner while adjusting the Camshaft gear timing mark to match the tensioner's top timing mark. Start by removing Camshaft sprocket bolts followed by the Timing Chain removal with the Camshaft and crankshaft sprockets. After disposing of the Timing Chain Tensioner bolts the technician will remove the Timing Chain Tensioner component. Constructors should discard the Camshaft position actuator filter found at the Camshaft's end. Mount a fresh Camshaft position actuator filter to the end of the Camshaft before securing the crankshaft sprocket with preapplied lubricant to the surface of the thrust. The Timing Chain Tensioner requires bolts installation with a torque of 21 n.m (15 lb ft). Put the tensioner retaining pin into the retaining hole while using the en-47719 tensioner compressor (EN-47719) to fully collapse the tensioner. Fit the crankshaft timing mark to the timing mark on the bottom of the Timing Chain Tensioner while suspending the Camshaft sprocket and Timing Chain then install them to the crankshaft gear. Position the timing mark from the Camshaft gear directly below the timing mark on top of the tensioner and place the sprocket dowel into the Camshaft hole. Attract the Camshaft sprocket toward the Camshaft by using mounting bolts before tightening them up to 16 n.m (12 lb ft). Free the Timing Chain Tensioner's retaining pin before activating it and apply clean engine oil to the crankshaft and Camshaft sprockets before installing the engine front cover.

To replace the Timing Chain and sprockets, one has to first remove the engine front cover. Set the timing marks of the crankshaft to correspond with the timing mark on the bottom of the Timing Chain dampener, and then similarly align the camshaft gear timing mark with the timing mark on the top of the Timing Chain dampener. Next withdraw camshaft sprocket bolt, camshaft sprocket and timing drive and crankshaft sprocket then the bolts for the Timing Chain dampener. For installation, begin to install the crankshaft sprocket and pre-lube gm p/n 1052365 or equivalent on to the crankshaft sprocket thrust surface. Fitting the Timing Chain dampener as well as its nuts tighten to 21 nm (15 lb ft). Lining crank shaft timing mark up with the timing mark at the base of the Timing Chain dampener, aligning camshaft sprocket with the Timing Chain hanging down, install the Timing Chain to the crank shaft gear. Ensure the timing mark on disk for timing mark camshaft gear is at the same position as the timing mark on top of Timing Chain dampener, and ensure the dowel on the camshaft perfectly aligns with the dowel hole on the camshaft sprocket. Mount the camshaft sprocket to the camshaft using the mounting bolt after coating the crankshaft and camshaft sprocket with engine oil and tighten the bolt to 140 n.m (103 lb ft). Draw the camshaft sprocket on the camshaft. Finally, set up the engine front cover.

Install the crankshaft sprocket and apply Engine Oil Supplement (EOS) GM P/N 1052367 or an equivalent to the sprocket thrust surface.

Insert the tensioner retaining pin into the retaining hole.

Repeat the process for the camshaft gear, aligning the timing mark on the camshaft gear with the timing mark on top of the timing chain dampener.

Align the timing mark on the camshaft gear with the timing mark on top of the timing chain dampener, ensuring the dowel in the camshaft fits into the dowel hole in the camshaft sprocket.

Begin by installing the crankshaft sprocket using the Crankshaft Sprocket Installer (J38612).

Remove the timing chain dampener bolts and the timing chain dampener itself.

Insert the tensioner retaining pin into the retaining hole.

Align the crankshaft timing mark with the timing mark on the bottom of the timing chain dampener and the timing mark on the camshaft gear, center line of the locator hole, with the timing mark on the top of the chain dampener.

First, remove the engine front cover.

Align the crankshaft timing mark with the timing mark on the bottom of the timing chain dampener and the timing mark on the camshaft gear, center line of the locator hole, with the timing mark on the top of the chain dampener.

The timing mark should be at the 5 o'clock position.

Finally, install the engine front cover.

Reinstall the engine front cover.

Install the timing chain dampener, ensuring to tighten the dampener bolts to 21 Nm (15 ft. lbs.).

Align the dowel in the camshaft with the dowel hole in the camshaft sprocket, then draw the camshaft sprocket onto the camshaft using the mounting bolt.

Hold the camshaft sprocket with the timing chain hanging down and install the timing chain to the crankshaft gear.

Repeat the process for the intake camshaft actuator, ensuring to remove the timing chain through the top of the cylinder head, followed by the timing chain crankshaft sprocket.

Remove the installer.

Remove the timing chain dampener bolts and the timing chain dampener itself.

Align the crankshaft timing mark with the timing mark on the bottom of the timing chain tensioner, hold the camshaft sprocket with the timing chain hanging down, and install the timing chain to the crankshaft gear.

Finally, install the timing chain dampener and tighten the timing chain dampener bolt to 22 Nm (16 ft. lbs.).

Do not turn the crankshaft or camshaft without the timing belt/chain installed or if the camshaft timing is unconfirmed.

Coat the crankshaft and camshaft sprocket with engine oil and reinstall the engine front cover.

Install the timing chain dampener and tighten the timing chain dampener bolt to 22 Nm (16 ft. lbs.).

Tighten the timing chain tensioner bolts to 10 Nm (89 inch lbs.).

Install the timing chain dampener and its bolts, tightening the timing chain dampener bolt to 21 Nm (15 ft. lbs.).

Remove the camshaft sprocket bolts, followed by the timing chain, camshaft, and crankshaft sprockets, and then the timing chain tensioner bolts and the tensioner itself.

Ensure the correct fasteners are used in the correct locations, and tighten the upper balance shaft chain guide bolts to 15 Nm (133 lb in).

Coat the crankshaft and camshaft sprockets with clean engine oil and install the engine front cover.

Coat the crankshaft and camshaft sprocket with engine oil and reinstall the engine front cover.

Install the camshaft thrust plate and its bolts, tightening them to 15 Nm (11 ft. lbs.), followed by the balance shaft drive gear.

Remove the camshaft sprocket bolts (206), followed by the camshaft sprocket (205) and timing chain (208), then take out the timing chain dampener (232) and bolts (231).

Use the Crankshaft Gear Puller (J 5825-A) to remove the crankshaft sprocket.

Remove the timing chain dampener bolts and the timing chain dampener itself.

Install the engine front cover.

The J 38612 Crankshaft Sprocket Installer (J 38612) is used.

Begin by removing the engine front cover.