GM 12560967
Camshaft

The first step before Camshaft replacement involves removing the Camshaft cover and Camshaft sprocket bolts installed on the intake and exhaust. Install the Camshaft sprocket holding tool (J 44222) onto the Cylinder Head by screwing in the horizontal bolts which tense the chain against Camshaft sprockets and prevent Timing Chain component disturbance. Start by moving the sprockets with their attached timing chains away from the camshafts before you take out the Camshaft cap bolts according to a systematic placement of the Camshaft caps in their installation rack. First remove the Camshaft caps before storing them and proceed to take out the camshafts. Prior to installation apply cleaned engine oil to the thrust face and Camshaft journals along with the lobes followed by placing the intake and exhaust camshafts at their original positions. Install the Camshaft holding tool (J 44221) so its flats face upward when setting the number 1 cylinder at top dead center. Users must install the appropriate fasteners in exact positions while eliminating all paints and lubricants that may influence torque measurements. The Camshaft caps should install in their original location because their directional and numerical orientation is stamped on them. Also tighten each Camshaft cap bolt to 12 nm (106 inch lbs.). Use the Camshaft holding tool (J 44221) to keep the Camshaft flats pointed up at cylinder number 1 tdc before removing it. Then carefully shift the sprockets onto the camshafts and remove this Camshaft sprocket holding tool (J 44222). Fasten the intake Camshaft sprocket washer along with its bolt and the exhaust Camshaft actuator bolt to 20 nm (15 ft. Lbs.) on the first round before an extra 100° tightening with the torque/angle meter (J 36660-A). The torque wrench should be set to 25 nm (18 ft. Lbs.) for the initial tightening of the exhaust Camshaft actuator bolt yet the torque/angle meter (J 36660-A) must be used for a second tightening procedure adding 135° of additional angle. Finally, install the Camshaft cover.

To replace the cam shaft, the negative cable of the battery should be disconnected and the engine cover should be removed after which the radiator, the air-conditioning condenser and the engine cooling fan, the valve lifters, the timing chain, the camshaft sprocket, and then the balance shaft drive gear are removed. Then extract the camshaft retaining bolts and retaining holes and get the engine camshaft out by inserting three 5/16-13 x 4.0 inch bolts through the front bolt holes and use them as a handle to rotate and pull the camshaft out of the bearings and then remove the bolts. Clean and check the camshaft and bearings and when a new camshaft is installed, use new engine oil and an oil filter and also add GM Engine Oil Supplement GM P/N 1052367 (Canadian P/N 992367) or equivalent to the engine oil. Apply clean engine oil GM P/N 12345610 (Canadian P/N 993193) or equivalent, or engine oil supplement GM P/N 1052367 (Canadian P/N 992367) or equivalent to lobes of camshafts, bearing journals and bearings. Put the engine camshaft there by using three bolts as the handle and then take out the bolts. When reusing, apply GM threadlock P/N 12345382 (Canadian P/N 10953489) or similar to the threads of the camshaft retainer bolts; then, install the camshaft retainer and the bolts with 12Nm (106inch lbs.) of torque. Fit the balance shaft drive gear, timing chain, camshaft sprocket, valve lifters, A/C condenser, engine cooling fan and radiator, top up the engine cooling system, replenish the air-conditioning system and finally fit the engine cover and lastly connect negative battery cable.

The replacement of the Camshaft requires the removal of radiator support and engine front cover and valve lifters followed by Camshaft sensor bolt and sensor teardown. The engine must rotate for the timing marks between Crankshaft and Camshaft sprockets to align but do not rotate the Crankshaft after Timing Chain removal to defend against piston assembly or valve damage. The Camshaft sprocket should come off next while moving the Timing Chain into position after which install the Camshaft retainer bolts and retainer. When removing or installing the Camshaft handle the bearing surfaces by placing three m8-1.25x100 mm (M8-1.25x4.0 in) bolts into the front bolt holes of the Camshaft to execute a controlled extraction from the engine block. Clean the components if needed before performing an inspection of both the Camshaft and the bearings. Cleaning engine oil should be used for lubricating Camshaft journals and bearings before reinstalling the Camshaft with the same three bolts into the engine block. The installation requires removal of the bolts while placing the retainer plate with its sealing gasket toward the engine block. Also ensure the gasket surface remains clean during this step. Place the Camshaft retainer while tightening its bolts to 25 nm (18 ft. Lbs.). Then install the sprocket after positioning the Timing Chain and secure the sprocket bolts at 35 nm (26 ft. Lbs.). Clean engine oil should be applied to the intact Camshaft sensor o-ring seal before installing the Camshaft sensor along with its bolt while torquing to 25 nm (18 ft. Lbs.). The last steps involve mounting the valve lifters together with the front cover along with the radiator support.

The hood hinge bolt removal starts by raising the hood to its service position then breaking the hood hinge bolts before pulling the hood vertical to tighten the hinge bolts in their service position . Start by taking out the radiator support and front cover as well as the valve lifters and Camshaft sensor bolt and sensor. The Crankshaft requires rotation until the timing marks between Crankshaft and Camshaft sprockets become aligned before removing the Camshaft sprocket bolts. The Crankshaft assembly must not spin after removing the Timing Chain since this leads to piston assembly and valve damage. Users must first extract the Camshaft sprocket and move the Timing Chain into position before detaching both Camshaft retainer bolts and retainer. To safely remove and install the Camshaft protect the Camshaft bearings while placing three m8-1.25 x 100 mm (M8-1.25 x 4.0 inch) bolts into the front bolt holes as a Camshaft extraction tool. You should clean and perform an inspection of both the Camshaft and bearings when needed. The three installation bolts can be reused to guide the engine block installation of the Camshaft before the bolts get removed. Lay the retainer plate with its sealing gasket touching the engine block and keep the gasket surface clean before installing the Camshaft retainer and bolts that need to be tightened to 25 nm (18 ft. Lbs.). Begin by attaching the Camshaft sprocket to the engine then position the Timing Chain followed by Camshaft sprocket bolt tightening to 35 nm (26 ft. Lbs.). You must inspect the Camshaft sensor o-ring seal for signs of damage before proceeding. The Camshaft sensor o-ring seal can be used if intact; apply clean engine oil to it before sensor installation and bolt tightening at 25 nm (18 ft. Lbs.). After installing valve lifters continue installation with front cover and radiator support pieces. Put the hood in its normal position and screw in the hood hinge bolts to a torque of 25 nm (18 ft. Lbs.).

The Camshaft replacement process requires step-by-step removal of the radiator support, engine front cover, valve lifters and Camshaft sensor bolt alongside sensor. After the sprocket timing marks align between the Camshaft and Crankshaft it is critical to refrain from rotating the Crankshaft assembly once the Timing Chain has been removed to protect valve assemblies and piston assemblies. After removing the Camshaft sprocket place the Timing Chain in its proper position and install the Camshaft retainer bolts and retainer while keeping an eye out for Camshaft bearing damage since all Camshaft journals share the same diameter. Three m8-1.25x100 mm bolts (M8-1.25x4.0 inch) should be inserted through the front holes of the Camshaft and used as tools to gently extract the component from the engine block after which the bolts can be removed. Cleaning and inspecting procedures should happen to Camshaft bearings and Camshaft components. After oiling the Camshaft journals and bearings with clean engine oil the three bolts can be used to reinstall the Camshaft inside the engine block until bolt removal is completed. Position the retainer plate toward the engine block so the gasket points outward while maintaining the gasket surface clean and free of contaminants. After positioning the Timing Chain, install the Camshaft sprocket before tightening the Camshaft sprocket bolts to 35 nm (26 ft. Lbs.). The Camshaft retainer and bolts should be installed now with a torque of 25 nm (18 ft. Lbs.). Examine the o-ring seal of the Camshaft sensor for signs of damage. In case the Camshaft sensor o-ring remains undamaged you must apply clean engine oil before installing the sensor and retaining bolt which requires torque to 25 nm (18 ft. Lbs.). Run valve lifters through installation steps with front cover and radiator support.

To replace the Camshaft do the following: remove the Radiator, air conditioning (A/C) condenser, lifters, timing chain, and cam shaft sprocket, and then balance shaft drive gear. Second, remove the retaining bolts for the Camshaft and the retainer while being careful not to damage Camshaft bearings because all the Camshaft journals are of the same diameter. Insert three 5/16-18 x 4.0 inches bolts into the front bolt holes of the engine Camshaft, and use it as a grip on which to rotate and pull the engine Camshaft out of the bearings before then removing the bolts. Polish and check the Camshaft or bearings as necessary. When replacing a new Camshaft, it is advisable to change the engine oil and filter, as wells as add the engine oil supplement. Oiling engine Camshaft lobes, Camshaft bearing journals, and Camshaft bearings. Turn the engine Camshaft using the bolts to act as a handle and then take off the bolts. In case of reused fasteners, put threadlock on the threads of the Camshaft retainer bolts. Mount the Camshaft retainer along with the bolts and tighten the nuts to 12 nm (106 inch lbs) followed by the balance shaft drive gear, timing chain, Camshaft sprocket, lifters, a/c condenser, and finaly the Radiator.

Tighten them to 12 Nm (106 inch lbs.).

Clean and inspect the camshaft and bearings before lubricating the camshaft journals and bearings with clean engine oil.

Install three M8-1.25 x 100 mm bolts into the front bolt holes of the camshaft, using them as a handle to carefully rotate and pull the camshaft out of the engine block, then remove the bolts.

Install the valve lifters, front cover, and radiator support.

Inspect it for damage; if intact, lubricate it with clean engine oil and install the camshaft sensor and bolt, tightening the bolt to 25 N.m (18 lb ft).

Apply Threadlocker GM P/N 12345382 (Canadian P/N 10953488) to the threads of the camshaft retainer bolts, install the camshaft retainer and bolts, and tighten them to 12 Nm (106 inch lbs.).