OEM GMC Envoy Timing Chain

GMC Envoy Timing Chain Parts Questions & Experts Answers

• Timing Chain
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  Q: What tools are required to replace the timing chain, sprockets, or tensioner on GMC Envoy?

  A: The Timing Chain, sprockets, or tensioner replacement will require the following tools: torque angle meter (J 36660-A) and camshaft holding tool (J 44221). First, remove the camshaft cover and the engine front cover. Relax the tension for Timing Chain by moving the shoe of the tensioner inward and position a tee at the tensioner to hold the shoe back. Displace the top chain guide bolts and top chain guide, then exhaust camshaft position actuator bolt and actuator, then intake camshaft sprocket bolt and sprocket. Then strip the Timing Chain off, crankshaft sprocket, cylinder head access hole plugs, Timing Chain Tensioner shoe bolt, tensioner shoe, Timing Chain Tensioner guide bolts, Timing Chain Tensioner guide, Timing Chain Tensioner bolts and Timing Chain Tensioner. For installation secure the Timing Chain Tensioner by bolting it at 25 nm (18 ft. Lbs.) after which secure the Timing Chain Tensioner guide and shoe at 10 nm (89 inch lbs.) and 26 nm (19ft. Lbs.) respectively. Desociate the cylinder head access hole plugs, securing it using 5 nm (44 inch lbs.). Use the camshaft holding tool (J 44221) with camshaft flats up and running the number 1 piston is at top dead center and install the crankshaft sprocket as well as the intake camshaft sprocket into the Timing Chain making sure the dark link overlaps the timing marks. Feed the Timing Chain down through the head opening and pick it up to the crankshaft sprocket, aligning with the timing mark. Mount the intake camshaft sprocket on the intake camshaft with the washer/bolt, tighten the bolt to 20 nm (15 ft. Lbs.) then use torque angle meter (J 36660-A); an additional 100 degrees of torque. Install the exhaust camshaft actuator into the Timing Chain with the direction of the dark link proceeding in line with the timing mark and fasten it on the exhaust camshaft using the actuator bolt, screwing it initially to 25 nm (18 ft. Lbs) and then utilize the torque angle meter (J 36660-A) for another pass further by 135 degrees. Take off the tee from the Timing Chain Tensioner, and then camshaft holding tool (J 44221), keeping the dark lines on the chain in alignment with the marks on the sprockets. Finally, install top chain guide with threadlock gm p/n 12345496 on bolt threads, secure top chain guide bolts to 10 nm (89 inch lbs.), and replace the engine front cover and camshaft cover.