Genuine Chevrolet Trailblazer Timing Chain

Chevrolet Trailblazer Timing Chain Parts Questions & Experts Answers

• Chain Assembly, Tmg
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  Q: How to disconnect the battery and replace the timing chain in V8 engine on Chevrolet Trailblazer?

  A:

  Remove the battery cable from the negative terminal, and drain out the cooling system and the engine oil, and then remove the upper and the lower fan shrouds, drivebelt, cooling fan and the water pump. Eliminate the crankshaft balancer and also the oil pan in order to access the bearings. For the 2005 on models, remove the mounting bolts and the camshaft position sensor comes off as well. Remove the mounting bolts that secure the timing chain cover and, in case this requires additional force, use a putty knife to loosen up the gasket but without harming the aluminum piece. The oil pick-up tube and the oil pump should be removed to take measurements of the timing chain freeplay; anything over 5/8 of an inch should have a new chain and both sprockets put in. The next steps are to slack off the camshaft sprocket bolts, turn the crankshaft so that its timing mark is in line with the number one cylinder and make sure number one piston is also at TDC. Take out the bolts that are at the end of the camshaft, and, therefore, the camshaft sprocket and the chain. For 2005 on models, the timing chain damper will have to be removed. Check the camshaft and crankshaft sprockets of its fitness to proceed, if required, remove the crankshaft sprocket gently. While your car is still off, turn the engine by gripping the top of the crankshaft to feel for any form of push back at least turn it two more times. Timing chains should be replaced in sets with the sprockets and gasket scraper should be used to remove old materiel from the cover and engine block. Bolt the timing chain damper and then engage the crankshaft sprocket with the Woodruff key, and then push on to the crankshaft. Thread the new chain through the front and rear sprockets so the timing marks line up and apply a thread locking compound to the sprocket bolt threads before torquing the bolt. Oil the chain with clean engine oil, fit in the oil pump and oil pick-up tube and loosely fit the timing chain cover with a new gasket. The timing chain cover doesn't need the oil pan rail be perfect on each end, just make them even, then Tighten the cover bolts. Use RTV sealant round the lower edge of the timing chain cover onto the cylinder block, fit the oil pan on, and do the other components fitting as the instruction in the reverse order. Last step is to put some coolant and oil and start the vehicle and look for the any leakage in the engine.