This response provides a *general overview* of the process. Consult a detailed repair manual specific to your year and model Sunfire. These manuals provide precise instructions, torque specifications, and diagrams crucial for success.
General Steps (Highly Simplified):
1. Preparation: Disconnect the battery, drain coolant, and remove the air intake system, fuel lines, and other components obstructing access to the engine's top end. You'll likely need to remove the valve cover.
2. Timing Chain/Belt Removal: This is critical. You'll need to properly identify the timing chain/belt's position and use appropriate tools to remove and protect it from damage. Incorrect reinstallation will result in catastrophic engine failure. Pay close attention to the timing marks.
3. Camshaft Removal: Remove the camshaft retainers and carefully remove the camshaft. Note its position relative to the timing chain/belt.
4. Lifter Removal: Remove the old lifters. They may be stuck, requiring careful persuasion with appropriate tools. Do not damage the lifter bores.
5. Installation of New Parts: Install the new lifters. Ensure they're seated correctly and lubricated. Install the new camshaft, ensuring it's properly aligned with the timing chain/belt.
6. Timing Chain/Belt Reinstallation: This is the most crucial step. Reinstall the timing chain/belt meticulously, ensuring all timing marks are perfectly aligned. Incorrect alignment will result in valve-to-piston contact and engine destruction.
7. Reassembly: Reinstall all removed components in the reverse order of removal, paying close attention to torque specifications for all bolts and nuts. Reinstall valve cover, air intake, etc.
8. Verification: Once everything is reassembled, check for any leaks. Start the engine and listen for any unusual noises. A mechanic's stethoscope can help pinpoint problems.
Tools You'll Need (Not Exhaustive):
* Repair Manual: Absolutely essential.
* Socket set and wrenches: Various sizes.
* Torque wrench: Accurate torque is crucial.
* Timing chain/belt tools: Specific tools are needed to work with the timing system.
* Valve spring compressor: If you're replacing valve seals (often recommended with a camshaft replacement).
* Camshaft installation tool: May be necessary to properly install the camshaft.
* Lifter installation tool (if needed): Some lifters may require specialized tools.
* Jack stands: Essential for safety.
* Clean workspace: Keeps parts organized and prevents damage.
Strong Recommendations:
* Professional Help: This is a complex job. Unless you have extensive experience with engine repair, it's highly recommended to have a qualified mechanic perform this service.
* New Timing Components: Consider replacing the timing chain/belt and tensioner while you're in there. These components wear over time and could fail soon after the camshaft and lifter replacement.
* Engine Oil and Filter Change: Change the engine oil and filter after the job is complete.
This overview is for informational purposes only. Do not attempt this repair without a detailed repair manual and the appropriate tools and experience. Incorrect installation can result in severe engine damage, requiring costly repairs or even engine replacement.
