Here's what's involved, but this is not a substitute for a professional repair manual specific to your 1987 Buick 3.8L engine:
1. Consult a Factory Service Manual: You absolutely must have a factory service manual for your specific year and model Buick. This manual will give you the precise procedures, diagrams, and specifications for timing chain replacement or adjustment. Trying this without one is extremely risky and can cause catastrophic engine damage.
2. Tools: You'll likely need special tools, including:
* Crankshaft Holding Tool: This tool prevents the crankshaft from rotating.
* Camshaft Alignment Tool: This tool may be required to correctly position the camshafts. Some methods use a degree wheel for precise camshaft timing.
* Timing Chain Installation Tool: This is often used to properly install the timing chain.
* Dial indicator (possibly): for advanced timing checks
3. Procedure (General Outline - Consult your service manual for specifics!): The general approach will involve:
* Removing the timing chain cover: This will expose the timing chain, sprockets, and related components.
* Removing the timing chain: This will require careful attention to the order of removal to avoid damaging components.
* Inspecting components: Inspect the sprockets, guides, and the chain itself for wear and damage. Replace any worn or damaged parts.
* Aligning the crankshaft and camshaft sprockets: The service manual will provide specific procedures and markings, likely involving alignment dowels or specific notch/pin positions. This is the critical step. The crankshaft and camshafts MUST be correctly aligned before the chain is installed. Misalignment can cause severe engine damage.
* Installing the new timing chain (if replacing): This often involves using a chain installation tool to ensure proper chain tension and avoid damage.
* Reassembling: Reinstall all components, ensuring proper torque specifications for all bolts.
Extreme Caution: Incorrect timing chain alignment can lead to bent valves, damaged pistons, and ultimately a destroyed engine. If you lack experience with engine repair, do not attempt this yourself. Take your vehicle to a qualified mechanic with experience working on Buick 3.8L engines. The cost of professional repair is far less than the cost of a rebuild or replacement engine.
