Changing GM 2.9L Timing Chain and Guides Removal
Disassemble Timing Chain on 2.9L GM
Drain the coolant by removing the bottom radiator hose. Drain the oil.
Remove the air filter housing and duct.
Loosen 2 bolts, then remove intake sound canceling chamber and duct on throttle body by loosening clamp.
Unplug, loosen 4 bolts and remove throttle body.
Loosen bolt and remove map sensor from top of intake manifold, or unplug.
Unplug all coil packs, unplug other sensors on top near valve cover while following the harness.
Loosen and unscrew the fan using the fan clutch removal kit with an air hammer. Left is loosen.
Remove clamp and pull off top radiator hose.
Pop open the plastic line attachment on the drivers side holding the ac line.
Remove the fan shround and fan together.
Remove the belt, then remove the tensioner.
Remove the waterpump pulley, then remove the waterpump itself.
Remove the crankshaft pullery with the harmonic balancer removal tool.
Jack up the vehicle, support on jack stands located on the frame, and remove both front wheels.
Remove drivers side inner wheel well – a bunch of plastic push pins. Pull out center of pin to release. Fight and wiggle it out of there.
Loosen bolts to alternator. 2 are accessible at the top, one is accessible through wheel well. You can disconnect and remove the alternator, or pull it out of the way.
With a long extension, impact, and swivel sockets, by going through the wheel well remove a metal cover on the intake manifold. A few wires are attached to it.
Up top, remove the bracket that attaches the dipstick tube to the intake manifold.
Then with the same extension, impact, and swivel sockets, remove all the bolts to the intake manifold. The bolts are in the following pattern from front to back.. 1, 2, 1, 2, 1. Be sure to get them all.
Pull the intake manifold back far enough to get to the valve cover bolt taht it was hiding. Loosen all bolts and remove valve cover.
4WD ONLY STEP!! Quick overview only, do on both front wheels – Remove brake caliper bracket bolts, set caliper aside. Loosen tie rod bolt, remove tie rod. Remove the axle nut. Remove the wheel speed sensor. Loosen upper ball joint nut, loosen lower ball joint nut, then smack knuckle downwards to free of joints, then set knuckle aside.
4WD ONLY STEP!! Remove both front axles by prying the axle away from the differential. Remove front driveshat caps, set driveshaft to the side. Unplug the axle lockout. Slide a jack under the differential. Remove the 4 bolts holding the differential to the frame. Set aside the differential.
Locate steering rack attachment bolts. Two large ones on the left, two bolts and a strap on the right. Loosen and remove bolts. Let rack hang.
Remove the oil pan. 3 bolts in the front. Several bolts going down the sides. 4 bolts that hold the pan to the transmission. 2 bolts revealed by removing the rubber torque converter housing access plug. Using two oil pan bolts, insert bolts into the provided threaded parts of the pan to "push" it away from the block. These threaded holes are located near the rear of the pan.
Remove the oil pickup tube. Save the gasket.
Loosen the bolts to the AC compressor through wheel well. It is important to note that the bottom right bolt can not be accessed with the steering rack installed. You can completely remove the bolts, or loosen until almost out. Slide the compressor away from the block.
Remove the front cover. Several bolts around the outside of the cover, a few bolts near the center above the crankshaft. Will be hard to pry off.
Now turn the engine until the timing marks on the camshafts are as follows... the exhaust cam (passenger side) will be on at the 11 o'clock position, the intake camshaft will be at the 1 o'clock postion.
Loosen the intake camshaft sprocket bolt.
Remove the two bolts and tensioner assembly.
Remove the driverside guide bottom bolt.
Remove the two plugs on the front of the cylinder head, which exposes the single bolt on each side holding the top of the guide. Remove both guides.
Remove the intake camshaft sprocket.
On my project, I could not remove the exhaust cam sprocket. We took the camshaft out entirely by loosening the cam cap bolts slowly, starting in the middle and working toward the outside. The cam caps are marked, but note exact location and direcetion. It MUST be reassembled in the same fashion.
Lift the camshaft up, then remove the chain.
Thats all for disassembly. Continue on for Reassembly directions.