GM 90537632
Camshaft Gear

To service and repair the Camshaft gear and sprocket, you'll need the following tools: tensioner tool (J 45027). Remove the negative cable from the battery, remove the Camshaft cover, and lift and block the vehicle. Next, take off the engine front cover and let the vehicle down. Finally, unbolt the Camshaft cover once more and use a 24 mm open-end wrench to turn the Camshaft clockwise to align the no. 1 piston at around 60 degrees before top dead center. Remove the spark plugs to accelerate rotation and the Timing Chain Tensioner, the upper Timing Chain Guide, and hold the camshafts with a 24 mm wrench. Proceed to unfasten the exhaust Camshaft sprocket bolt and sprocket, the Timing Chain Tensioner guide, the Engine Mount, the fixed Timing Chain Guide access plug, and the fixed Timing Chain Guide. Discard the intake Camshaft sprocket bolt and remove the intake Camshaft sprocket then take off the Timing Chain from the top of the cylinder head then remove the crankshaft sprocket, oil nozzle and bolt, balance shaft drive chain tensioner, adjustable balance shaft chain guide, small balance shaft drive chain guide, and upper balance shaft drive chain guide. To make it easier to remove the balance shaft drive chain, ensure all the slack for the chain will be between the crankshaft and water pump sprokets. For installations, begin with the upper balance shaft chain guide and tighten its bolts to 10 nm (89 inch lbs), followed by the small balance shaft chain guide and adjustable balance shaft drive chain guide tighten each of these bolts to 10 nm (89 inch lbs). Twist the tensioner plunger by 90 degrees and squeeze it until a paper clip can be inserted, then install the timing link tensioner and tighten the bolts of the 10 nm (89 inch lbs.). remove the paper clip, install an oil nozzle and bolt confident with 10 nm (89 inch lbs.), and install a crankshaft sprocket with the timing at the 5 o"clock position. Lower the Timing Chain through the opening in the cylinder head, making sure it winds its way around both sides of the cylinder block bosses, then fit the intake Camshaft sprocket with the int diamond at the 2 o'clock position and hand tighten a new intake Camshaft sprocket bolt. Route the Timing Chain over the crankshaft sprocket and over the intake Camshaft sprocket so that the Timing Chain lines up in its colored links with its timing marks. Arranging the Timing Chain matching colored link at the exh triangle, install the exhaust Camshaft sprocket at the 10 o'clock position tight the bolted of the Timing Chain with a torque of 10 nm (89 inch lbs) seize the Timing Chain Tensioner guide. Channel the Camshaft a little using a 24 mm wrench to get the exhaust sprocket into position, then hand tighten a new-bolt creature exhaust Camshaft sprocket, also install the fixed Timing Chain Guide, tighten its bolts to 10 nm (89 inch lbs.). Seal, gm p/n 12345382 (Canadian P/N 10953489), to the Timing Chain Guide bolt access hole plug, and tighten to 90 nm (66 ft. Lbs.). Mount the Engine Mount, check the Timing Chain Tensioner for damage, and measure or take the assembly from end to end and ensure it is in a compressed state of 72 mm (2.83 in). If not, apply steps needed to compress it in j 45027-2 and j 45027-1 . Clean the threaded hole of the Timing Chain Tensioner, install the new Timing Chain Tensioner assembly, and tighten 75 nm (55 ft. Lbs.). Compress the tensioner 2 mm (0.079 in) with an appropriate tool and use a 24 mm wrench to hold the Camshaft and tighten the new Camshaft bolts to 85 nm (63 ft. Lbs.) turned 30 degrees added. Last of all, to install the Camshaft cover, lift the vehicle, install the engine front cover, let the vehicle down and reconnect the negative Battery Cable.

To replace the Timing Chain and the sprockets, remove the engine front cover. Turn the Crankshaft to have the timing marks lined up at the camshaft alignment pin and Timing Chain dampener to the Crankshaft sprocket. Now, pull off the camshaft sprocket bolt, the camshaft sprocket with the Timing Chain and finally, the Crankshaft sprocket. Take off the Timing Chain dampener bolts and the Timing Chain dampener. If required, unbolt the thrust plate from the camshaft and remove the thrust plate and the thrust plate bolts. Replace damaged spark plug wire withitezlonese or swivel yoke and gear. For installation, if the camshaft thrust plate had been removed, install then and tighten the thrust plate bolts with 10 nm (89 inch lbs). Install the Crankshaft sprocket applying the engine oil supplement (EOS). The required part number is gm p/n 1052367 (Canada P/N 992869) or equivalent to the thrust surface of the sprocket. Mount the Timing Chain dampener and apply a torque of 21 nm (15 ft. Lbs.) to the dampener bolts. Mount the Timing Chain over the camshaft gear while allowing the camshaft to rest on the chain's underside, let the chain rest on the Crankshaft Gear. The Crankshaft timing mark is aligned in the middle of its sprocket with the timing mark of the bottom of the Timing Chain dampener and the timing mark of the camshaft gear, center line of the locator hole with the timing mark of the top of the chain dampener . Ensure that the dowel in the cam shaft finds its place correctly in the dowel hole in the camshaft sprocket. Mount the camshaft sprocket on top of the camshaft using the mounting bolt and torque the camshaft sprocket bolt to 140 nm (103 ft. Lbs.). Finally, paint a layer of engine oil on the Crankshaft and camshaft sprocket and return the engine front cover.

Use a 24 mm wrench (J 44217) to hold the camshaft while loosening, but not removing, the intake camshaft actuator bolt.

The upper timing chain guide bolts and guide, followed by the timing chain tensioner.

First, remove the camshaft cover and the upper timing chain guide bolts and guide.

Use the 24 mm wrench to hold the camshaft while tightening the NEW camshaft actuator bolt to 85 N.m (63 lb ft), plus an additional 30 degrees with the J 45059 Angle Meter.