Buick 12646387 Chain Assembly, Tmg

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Some of the timing system can be quite difficult to manipulate and it is very easy to cause further damage to the engine if any wrong step is taken, thus it is highly recommended that only those who have considerable experience in such repairs attempt it; in any case, they should consult a professional. Recheck all work and make sure all are right before start the engine. Special tools are required to lock the camshafts on each cylinder head into position, with two designs for the sprockets and chains: The first models, from 2005 to mid-2007, employ Design 1, which involves using camshaft locking tools EN-46105-1 and EN-46105-2, while the later ones, from mid-2007 to 2014, use the tools EN-48383-1, EN-48383-2, and EN-48383-3 and comes with 'inverted tooth' chains for less First, you have to take off the timing chain cover and for models of 2005 and half of 2007, rotate the crankshaft to the position with the mark on the oil pump housing vertical in the nine o'clock position while the flat backlash on the ridge of each camshaft on the right-hand cylinder head faces upwards. Attention should be paid to the installation of the special tools to the camshafts, then unscrew the fixing bolts for the timing chain tensioner for the right-side cylinder head and, having removed it along with the gasket, carefully put it aside. Move on to the removal of the right side cylinder head timing chain guides and the chain then do the same thing on the left side of the cylinder head. If required, one can take off the idler sprockets and locate the position of the camshaft sprockets and the camshaft before taking off the sprocket bolt. As for the mid 2007 and onward models, there is a similar process that must be carried out, but the crankshaft comes to a specific position and proper locking tools used. Check the timing chain cover for damage, scrub all components and look for such signs of wear or damage as on guides and sprockets. Remove tension from the tensioners and make sure that they are to be kept in a compact mode. When positioning of the crankshaft sprocket, woodruff key should be fitted with the timing marks visible and aligned before fitting the timing chains and the guides with the bolts tightened to the stipulated torque. Once more tighten all the timing marks appropriately, briefly turn the crankshaft to check for drag - which will signify a problem - before unlocking the tools.

The use of timing system is quite delicate and if an error is made on the same, there will be severe damages to the engine, thus, it is advisable that, only professionals try this process and in case there is any doubt, one should consult an expert. Start with the removal of the first end terminal of the battery then empty the cooling system and the engine oil. For 5.3L and 6.2L models, the oil pan, vacuum pump and coolant manifold need to be removed while on the other hand the AC compressor needs to be held in place while the lines do not need to be disconnected. On 6.0L models, some of the crops include; If equipped, disconnect the wiring from the camshaft position sensor and actuator magnet, remove the water pump, and take off the crankshaft balancer. The timing chain cover mounting bolts must be removed, care being taken not to mar the cover, and the oil pump must be detached. Force the timing chain tensioner towards the chain until a special tool or a 3 mm drill bit can be inserted, then turn the crankshaft until you have the timing marks lined up at twelve and six but do not or turn the camshaft or crankshaft until the chain is back into its position. After that, eliminate the solenoid valve that was attached to the upper sprocket assembly, and dispose of it Later, unbolt, the actuator from the camshaft and exhaust the actuator assembly with the chain as well. Check the wear condition and conditions of timing chain tensioner, camshaft and crankshaft sprockets and in case where the crankshaft sprocket has to be removed from the crank shaft do it gently. Timing chains should be replaced at one time with the camshaft and crankshaft sprockets; gasket material should be cleaned off the cover and engine block. Check the position of the crankshaft sprocket in regard to the Woodruff key and place it on the crankshaft but do not hammer it. New chain place the new chain over the camshaft sprocket and make sure that the chain marks are lined correctly and no part of the chain is out of the engine block. Check the new camshaft position actuator valve snugly and compress the timing chain tensioner then install it and rotate the crank shaft manually to as much as possible for resistance. Bolt on the oil pump, perform cleaning of sealing surfaces, apply RTV on sealing surfaces, tighten this loosely with gasket and use a cover aligner tool to rightly align the timing chain cover. Last, fit a new crankshaft oil seal, and follow the reverse procedure to that of the removal part for the rest of the fitting process; refill the cooling and engine oil, replace the engine oil filter, and look for leaks after the vehicle has been run for some time.

Pull the multiplug connector out of the negative battery terminal, then pull up and slide off the rear engine cover, then turn off the engine coolant and oil, remove the drive belts and tensioners. Extract the air filter housing and intake duct also, then unplug the upper and lower radiator hoses, the cooling fans and the water pump. Take out the crankshaft balance and, for all but the 5.7L engines, the Camshaft Position sensor and the sensor harness. The timing chain cover being the subject of removal it is not important to fully remove the oil pan, just unbolt it.For the removal of the oil pan, the following steps need to be followed:1. Draw the oil pan to front cover bolts with the aid of the plucker when bringing the extraction tool towards the car.2. Remove it from under the car. Fully remove the alternator along with the mounting bolts that are usually on the top of it. Take out the timing chain cover bolts; then take off the cover from the block, try to pry it with a putty knife if it is jammed. Locate and pull out the oil pick-up tube and oil pump taken out and check for the gears, chain and dampener for any signs of wear of damage. Relax the camshaft sprocket bolt(s), screw the crankshaft balance bolt into the crankshaft and with your fingers rotate the crankshaft until you get a alignment of the timing marks and ensure the same is set when the number one piston is at TDC. There is one or more bolt which needs to be unbolted at the end of the camshaft Camshaft sprocket and chain should be removed as a single unit. If replacing the tensioner, remove from the engine. Check damages and wears on camshaft and crankshaft sprockets, and if is required, take off the sprocket of the crankshaft by the puller. Timing chains should always be replaced together with the camshaft and crankshaft sprockets when it is being replaced. Then, using a gasket scraper, remove old gasket material from the cover and the engine block; about the crank shaft sprocket with the Woodruff key; and push it to fit on the crank shaft. Cinch the timing chain tensioner and place it in proper position and install the tensioner and fix the bolts tightly. The next step is to turn the sprockets in such manner that the coinciding timing marks are placed at the corresponding positions; in case if not, the sprocket must be rotated until the mark on the crankshaft is pointing upward, i. e. at 12. Place the chain around the crankshaft sprocket with the mesh and place the camshaft actuator or sprocket and align the timing mark. Take out the tensioner retaining pin and fasten the camshaft position actuator solenoid valve. Then lubricate the chain with clean engine oil and fit the oil pump and the oil pick-up tube, though at this stage you might want to change the crankshaft front oil seal. Remove the timing chain cover and fit a new gasket and loosely re-install the cover to make certain that it is in the correct alignment. If alignment tools are not possible, take a straight edge and measure from the rail of the oil pan to the timing chain cover on both sides and if uneven, make adjustments to be as even as possible. Turn the cover bolts until they are aligned, and place RTV sealant where there is contact between the timing chain cover and the cylinder block, and then fit the oil pan. Last but not the least, pour the coolant into the engine and oil into the crankcase and start the engine and search for any leaks.

Disconnect the cable from the negative terminal of the battery, drain the cooling system and engine oil, and remove the alternator. Next, take out the power steering pump, followed by the water pump and the camshaft position sensor. Disconnect the hoses from the coolant air bleed pipe and all hoses from the coolant manifold, securing them out of the way with wire. Use the correct power steering pulley removal tool to access the bolt behind the pulley, or alternatively, unbolt the power steering pump for clearance. Remove the crankshaft balancer and one of the belt tensioner bolts to access the timing chain cover bolts. Detach the timing chain cover from the block, taking care not to damage it, and remove the oil pump. Measure the timing chain freeplay; if it exceeds 5/8 inch, replace the chain and both sprockets. Loosen the camshaft sprocket bolts, rotate the crankshaft until the timing marks align, and verify that the number one piston is at TDC. Remove the camshaft sprocket and chain as an assembly, inspecting for damage or wear. If necessary, remove the crankshaft sprocket carefully. For installation, replace timing chains as a set with the camshaft and crankshaft sprockets, and use a gasket scraper to clean old gasket material from the cover and engine block. Align the crankshaft sprocket with the Woodruff key and press it onto the crankshaft, ensuring not to damage it. Loop the new chain over the camshaft sprocket, aligning the timing marks correctly, and apply thread locking compound to the camshaft sprocket bolt threads before tightening. Lubricate the chain with clean engine oil, install the oil pump and oil pickup tube, and replace the crankshaft front oil seal if needed. Install the timing chain cover loosely with a new gasket, aligning it properly by measuring the distance from the oil pan rail to the timing chain cover on both sides and adjusting as necessary. Once aligned, tighten the cover bolts, apply RTV sealant where the timing chain cover meets the cylinder block, and install the oil pan. Complete the remaining installation steps in reverse order, then add coolant and oil to the engine, running it to check for leaks.

Remove the battery cable from the negative terminal, and drain out the cooling system and the engine oil, and then remove the upper and the lower fan shrouds, drivebelt, cooling fan and the water pump. Eliminate the crankshaft balancer and also the oil pan in order to access the bearings. For the 2005 on models, remove the mounting bolts and the camshaft position sensor comes off as well. Remove the mounting bolts that secure the timing chain cover and, in case this requires additional force, use a putty knife to loosen up the gasket but without harming the aluminum piece. The oil pick-up tube and the oil pump should be removed to take measurements of the timing chain freeplay; anything over 5/8 of an inch should have a new chain and both sprockets put in. The next steps are to slack off the camshaft sprocket bolts, turn the crankshaft so that its timing mark is in line with the number one cylinder and make sure number one piston is also at TDC. Take out the bolts that are at the end of the camshaft, and, therefore, the camshaft sprocket and the chain. For 2005 on models, the timing chain damper will have to be removed. Check the camshaft and crankshaft sprockets of its fitness to proceed, if required, remove the crankshaft sprocket gently. While your car is still off, turn the engine by gripping the top of the crankshaft to feel for any form of push back at least turn it two more times. Timing chains should be replaced in sets with the sprockets and gasket scraper should be used to remove old materiel from the cover and engine block. Bolt the timing chain damper and then engage the crankshaft sprocket with the Woodruff key, and then push on to the crankshaft. Thread the new chain through the front and rear sprockets so the timing marks line up and apply a thread locking compound to the sprocket bolt threads before torquing the bolt. Oil the chain with clean engine oil, fit in the oil pump and oil pick-up tube and loosely fit the timing chain cover with a new gasket. The timing chain cover doesn't need the oil pan rail be perfect on each end, just make them even, then Tighten the cover bolts. Use RTV sealant round the lower edge of the timing chain cover onto the cylinder block, fit the oil pan on, and do the other components fitting as the instruction in the reverse order. Last step is to put some coolant and oil and start the vehicle and look for the any leakage in the engine.

Disconnect the cable from the negative terminal of the battery, drain the cooling system and engine oil, and remove the alternator. Next, take out the power steering pump, followed by the water pump and the camshaft position sensor. Disconnect the hoses from the coolant air bleed pipe and all hoses from the coolant manifold, securing them out of the way with wire. Use the correct power steering pulley removal tool to access the bolt behind the pulley, or alternatively, unbolt the power steering pump for clearance. Remove the crankshaft balancer and one of the belt tensioner bolts to access the timing chain cover bolts. Detach the timing chain cover from the block, taking care not to damage it, and remove the oil pump. Measure the timing chain freeplay; if it exceeds 5/8 inch, replace the chain and both sprockets. Loosen the camshaft sprocket bolts, rotate the crankshaft until the timing marks align, and verify that the number one piston is at TDC. Remove the camshaft sprocket and chain as an assembly, inspecting for damage or wear. If necessary, remove the crankshaft sprocket carefully. For installation, replace timing chains as a set with the camshaft and crankshaft sprockets, and use a gasket scraper to clean old gasket material from the cover and engine block. Align the crankshaft sprocket with the Woodruff key and press it onto the crankshaft, ensuring not to damage it. Loop the new chain over the camshaft sprocket, aligning the timing marks correctly, and apply thread locking compound to the camshaft sprocket bolt threads before tightening. Lubricate the chain with clean engine oil, install the oil pump and oil pickup tube, and replace the crankshaft front oil seal if needed. Install the timing chain cover loosely with a new gasket, aligning it properly by measuring the distance from the oil pan rail to the timing chain cover on both sides and adjusting as necessary. Once aligned, tighten the cover bolts, apply RTV sealant where the timing chain cover meets the cylinder block, and install the oil pan. Complete the remaining installation steps in reverse order, then add coolant and oil to the engine, running it to check for leaks.

Remove the front engine cover fasteners and the cover, followed by the rear cover fasteners and the rear cover.

Remove the drive belts, cooling tank, coolant manifold, crankshaft balancer, vacuum pump, and reposition the air conditioning compressor without disconnecting its lines. Then, take off the oil pan and oil pump, and remove the starter.

To remove the timing chain cover, you need to follow these steps:1. Disconnect the cable from the negative terminal of the battery.2. Drain the cooling system.3. Remove the cooling fan.4. Take off the water pump.5. Remove the drivebelt pulley.6. Remove the vibration damper.7. Remove the crankshaft position sensor and the wiring harness nut.8. Remove the oil pan.9. Disconnect the wiring harness clips from the front cover.10. Remove the crankshaft position sensor and the camshaft position sensor with its jumper wiring harness.11. Remove the cover bolts.12. Separate the timing chain cover from the block.13. Remove the crankshaft position sensor reluctor ring.14. Measure the timing chain free play.15. Replace the chain and sprockets if necessary.

For engines without camshaft position actuators, you should loosen the camshaft sprocket bolts, rotate the crankshaft until the timing marks align, and then remove the camshaft sprocket and chain as an assembly.

Align the timing mark with the 9 o'clock position.

Use a gasket scraper to clean the cover and engine block, align the crankshaft sprocket with the Woodruff key, and press it onto the crankshaft.

Wait until the engine is completely cool before beginning this procedure.

Remove the intake camshaft sprocket, unhook the chain from the crankshaft sprocket, and remove the chain while holding the camshaft stationary.

After disconnecting the battery, the coolant should be drained.

Remove the camshaft sprocket bolt(s) without turning the camshaft, using a TORX PLUS socket if applicable.

The final steps involve completing the reinstallation process in reverse order, filling the cooling system and engine oil, replacing the oil filter, and checking for any oil or coolant leaks during engine operation.

For engines with camshaft position actuators, you should rotate the crankshaft to align the timing marks, remove the solenoid valve, and detach the actuator assembly and chain.

Remove the crankshaft sprocket.

To install the timing chain cover, you need to follow these steps:1. Clean the engine block sealing surfaces.2. Align the keyway in the crankshaft sprocket.3. Press the sprocket onto the crankshaft.4. Align the balance shaft gears.5. Position the crankshaft and loop the chain over the camshaft sprocket.6. Apply thread locking compound to the camshaft sprocket bolt threads and tighten them.7. Install the crankshaft position sensor reluctor ring.8. Apply RTV sealant to the engine block sealing surface.9. Position the new front cover and oil seal assembly.10. Tighten the cover retaining bolts.11. Install the oil pan.12. Install the vibration damper.13. Install the crankshaft position sensor.

To install the timing chain cover, you need to follow these steps: 1. Clean the engine block sealing surfaces. 2. Align the keyway in the crankshaft sprocket. 3. Press the sprocket onto the crankshaft. 4. Align the balance shaft gears. 5. Position the crankshaft and loop the chain over the camshaft sprocket. 6. Apply thread locking compound to the camshaft sprocket bolt threads and tighten them. 7. Install the crankshaft position sensor reluctor ring. 8. Apply RTV sealant to the engine block sealing surface. 9. Position the new front cover and oil seal assembly. 10. Tighten the cover retaining bolts. 11. Install the oil pan. 12. Install the vibration damper. 13. Install the crankshaft position sensor.

Rotate the crankshaft by hand through at least two full revolutions, checking for resistance.

To remove the timing chain cover, you need to follow these steps:1. Disconnect the cable from the negative terminal of the battery.2. Drain the cooling system.3. Remove the cooling fan.4. Take off the water pump.5. Remove the drivebelt pulley.6. Remove the vibration damper.7. Remove the crankshaft position sensor and the wiring harness nut.8. Remove the oil pan.9. Disconnect the wiring harness clips from the front cover.10. Remove the crankshaft position sensor and the camshaft position sensor with its jumper wiring harness.11. Remove the cover bolts.12. Separate the timing chain cover from the block.13. Remove the crankshaft position sensor reluctor ring.14. Measure the timing chain free play.15. Replace the chain and sprockets if necessary.

You should tighten the camshaft sprocket bolt or the actuator valve to the specified torque.

To remove the timing chain cover, you need to follow these steps:1. Disconnect the cable from the negative terminal of the battery.2. Drain the cooling system.3. Remove the cooling fan.4. Take off the water pump.5. Remove the drivebelt pulley.6. Remove the vibration damper.7. Remove the crankshaft position sensor and the wiring harness nut.8. Remove the oil pan.9. Disconnect the wiring harness clips from the front cover.10. Remove the crankshaft position sensor and the camshaft position sensor with its jumper wiring harness.11. Remove the cover bolts.12. Separate the timing chain cover from the block.13. Remove the crankshaft position sensor reluctor ring.14. Measure the timing chain free play.15. Replace the chain and sprockets if necessary.

To remove the timing chain cover, you need to follow these steps:1. Disconnect the cable from the negative terminal of the battery.2. Drain the cooling system.3. Remove the cooling fan.4. Take off the water pump.5. Remove the drivebelt pulley.6. Remove the vibration damper.7. Remove the crankshaft position sensor and the wiring harness nut.8. Remove the oil pan.9. Disconnect the wiring harness clips from the front cover.10. Remove the crankshaft position sensor and the camshaft position sensor with its jumper wiring harness.11. Remove the cover bolts.12. Separate the timing chain cover from the block.13. Remove the crankshaft position sensor reluctor ring.14. Measure the timing chain free play.15. Replace the chain and sprockets if necessary.

You should tighten the camshaft sprocket bolt or the actuator valve to the specified torque.

The initial steps include disconnecting the negative battery cable and draining both the cooling system and engine oil.

Remove the intake camshaft sprocket, unhook the chain from the crankshaft sprocket, and remove the chain while holding the camshaft stationary.