Before you do any work on your car it is important that you wear safety glasses, work gloves and dispose of all fluids in a safe manner. Coolant is poisonous and should be treated as such. Animals and small children have been known to die from ingesting coolant. If you have to jack up your car, make sure to use jack stands and chock your wheels as well as applying the parking brake. Protect your eyes, hands and body from fluids, dust and debris while working on your vehicle. If you're working with the electrical system, disconnect the battery before beginning. Always catch fluids in appropriate containers and properly dispose of any fluid waste. Recycle parts, packaging and fluids when possible. Never work on your vehicle if you feel the task is beyond your ability. Always wear eye and hand protection.
One would think that when the engine is at speed there is a higher incidence of wear and eventual failure. This isn't necessarily true in the case of certain components, namely the timing chain. Chains, sprockets, gears and even bearings experience the most wear upon startup. The timing chain and the various components (guide rails, tensioning rail, chain tensioner) wear out after 100,000 miles and should be replaced. The sprockets should also be replaced. The chains can stretch but they also wear. As each rolling element of the link begins to experience wear it sets up for increased vibration and movement of the chain links and pins against the sprocket surface. As many teeth as the sprocket has, the chain has many more links. The sprocket surface wears down contributing to more movement as the chain passes over the sprocket surfaces. This creates an even greater opportunity for chain breakage.
The guide rails will be the first order of business to address. In order to change the guide rails in preparation for the replacement of the timing chain, all the components in front will have to be removed. This includes the belts, pulleys, alternator, the distributor and the power steering pump were all removed. Please refer to these articles should you need assistance.
I also removed the radiator. Normally you wouldn't have to do that but it was already out due to the development of another article. Refer to removing the radiator article for help in that regard.
Also, the distributor should be set at top dead center (TDC) and marked. This is needed when you put everything back. The distributor was also removed earlier. Hence, you can refer to the distributor removal article if you need assistance.
The valve cover will have to be removed as well. In order to do that you will have to remove the air box. Refer to the valve cover removal article for help on how to do that project.
The chain guide is held in place by bearing bolts. These devilish devices provide hours of frustration if not properly dealt with. There are several ways in which they can be removed. The easiest way is to use a tool offered up by Pelican Parts called a rail pin puller guide with a 6mm extractor. Please refer to the removing the chain guide article for more information.
The top guide rails should also be replaced. It is not necessary to remove the timing chain cover to get at the guides but it would make the job easier. The lower ones shall be replaced but require the removal of the timing chain cover. That task is also required for the timing chain replacement. Referring to this article will help you with that project.
The vibration dampener will have to be removed.
After the crankshaft pulley and vibration dampener have been removed, fit a gear puller to the flange edge of the hub.
After many rotations, the hub will become extracted. It will require about 2 inches before the hub is free enough to pull off with your hand. Be careful not to lose the key found in the keyway.
The hub is now free allowing access to remove the timing cover plate. To install, it is recommended to use a lubricant such as engine oil to allow the hub to slide back on. It is not recommended to use grease or anti-seize compounds. A hammer may be required but use a block of wood to tap it into place so you do not damage the edges.