Genuine GMC Yukon Variable Timing Sprocket

GMC Yukon Variable Timing Sprocket Parts Questions & Answers

• Sprocket, Camshaft
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  Q: How do you remove the timing chain and Sprocket on 4.3L V6 engine for Chevrolet Avalanche,Silverado,Suburban,Tahoe,GMC Sierra,Yukon,Yukon Denali and Yukon XL?

  A: To remove the timing chain cover, you need to first detach the negative cable from the battery and drain all the coolant. Afterwards, take out cooling fan, water pump, drive belt pulley and vibration damper. Then remove crankshaft position sensor and wiring harness nut. Remove Oil Pan then disconnect wiring harness clips from front cover. Remove crankshaft position sensor and camshaft position sensor with its jumper wiring harness. Afterward, remove the cover bolts and separate timing chain cover from block. Remove crankshaft position sensor reluctor ring and check timing chain free play. When needed replace the chain as well as sprockets. Be sure to align sprocket timing marks as well as release timing chain tensioner. To install timing chain cover clean engine block sealing surfaces then line up keyway on crankshaft sprocket. Press sprocket onto crankshaft while aligning balance shaft gears on opposite ends of shafts. Position crankshaft vis-à-vis camshaft sprocket in a way that allows passage of a looped chain over it. Apply thread locking compound onto camshaft sprocket bolt threads then tighten them up. Install crankshaft position sensor reluctor ring and apply RTV sealant to engine block sealing surface. Place new front cover and oil seal assembly in place plus tighten down on retaining bolts of cover afterward screws are tightened except for one at each end of upper edge of front plate where the attachment is made at an angle toward middle). Finally put back oil pan, vibration damper and then crankshaft position censor.