If you're not experienced with engine repair, you should take your car to a qualified mechanic. This is a critical system, and a mistake could cost thousands of dollars in repairs.
However, if you're determined to do it yourself, here's a general outline. This is *not* a complete, step-by-step guide, and it omits many crucial details. You'll need a detailed repair manual specific to your 1992 Cadillac DeVille 4.9L FWD. A Haynes or Chilton manual will be invaluable.
Before you start:
* Consult a repair manual: Obtain a repair manual specifically for your vehicle. This will provide detailed instructions, torque specifications, and diagrams.
* Gather tools and parts: You'll need specialized tools, including a timing belt tool kit (often includes crankshaft pulley holder, camshaft alignment tools, etc.), socket set, wrenches, jack stands, etc. Ensure you have the correct timing belt, tensioner, and any other worn parts you discover during the process.
* Safety first: Disconnect the negative battery terminal. Work in a well-ventilated area.
General Steps (Highly Simplified and Incomplete):
1. Preparation: Drain the coolant. Remove the serpentine belt. Remove various components that obstruct access to the timing belt, such as the air intake, various pulleys and brackets (consult your manual for the precise order and method).
2. Access the Timing Belt: Remove the lower timing cover. This will expose the timing belt, crankshaft pulley, and camshaft sprockets.
3. Mark Timing Belt Position: Carefully mark the relative positions of the crankshaft and camshaft sprockets to the timing belt. This is absolutely critical for correct reassembly. The marks should already be on the sprockets. If not, find the corresponding marks on the engine block.
4. Remove the Timing Belt: Loosen the tensioner to release the belt's tension. Remove the old timing belt.
5. Inspect Components: Inspect the timing belt tensioner, idler pulleys, and water pump for wear. Replace any worn components.
6. Install New Timing Belt: Install the new timing belt, ensuring it's aligned with the marks you made earlier. Use the appropriate tools to tension the belt correctly. This will involve tightening the tensioner to the specified torque.
7. Reassembly: Reinstall all removed components, ensuring everything is properly tightened to the manufacturer's specifications. Re-torque all bolts to proper specs.
8. Refill Coolant: Refill the cooling system with the correct coolant.
9. Test: Reconnect the battery, and start the engine. Listen for unusual noises. Check for leaks.
Again, this is a vastly simplified overview. Attempting this without a detailed repair manual is extremely risky. Improperly timed valves can cause serious engine damage. The process requires precise attention to detail and the use of specialized tools. If you're not comfortable with this level of automotive repair, take your vehicle to a qualified mechanic.
