This outline provides a general overview. Specific procedures may vary depending on the year and configuration of your 350. Always consult a reliable engine repair manual specific to your engine's year and model for detailed instructions and torque specifications.
I. Preparation:
1. Gather Tools & Materials: This includes engine stands, valve spring compressor, valve lapping tool, valve grinder (if necessary), feeler gauges, various sockets and wrenches, torque wrench, cleaning supplies (brake cleaner, etc.), new valve seals, gaskets (head gasket, intake manifold gasket, etc.), and possibly new valves and valve guides (depending on the condition). A complete list can be found in a repair manual.
2. Remove the Cylinder Heads: This involves disconnecting various components, including spark plugs, intake manifold, distributor, and accessories. The process requires careful attention to detail to avoid damage. Remember the order of components and take pictures as you go.
3. Inspect Components: Examine the cylinder heads, valves, valve seats, and guides for wear and damage. This will help determine the extent of the work needed. You may need to replace worn or damaged parts.
II. Valve Job Procedure (per cylinder):
1. Compress Valve Springs: Carefully compress the valve springs to remove the keepers and retainers. Use the valve spring compressor correctly to avoid damaging the springs or valves.
2. Remove Valves: Once the springs are compressed, remove the valves.
3. Inspect Valve Guides: Check the valve guides for wear. Excessive wear requires replacement.
4. Inspect Valve Stems and Seats: Examine the valve stems for wear or damage. Check the valve seats for wear, pitting, or cracking. This often requires specialized tools to assess precisely.
5. Valve Grinding (If Necessary): If the valve seats are worn, you'll likely need to use a valve grinder to refinish them to the correct angle. This requires skill and precision.
6. Valve Lapping (If Necessary): After grinding or if only minor lapping is required, lap the valves to ensure a proper seal. Use a lapping compound and lapping tool.
7. Install New Valve Seals: Install new valve seals onto the valve stems.
8. Install Valves: Carefully reinstall the valves, ensuring they're seated properly.
9. Reinstall Springs and Retainers: Reinstall the valve springs, keepers, and retainers using the spring compressor.
10. Repeat for All Valves: Repeat steps 1-9 for all valves in all cylinders.
III. Reassembly:
1. Install Cylinder Heads: Carefully install the cylinder heads, ensuring proper alignment and torqueing the head bolts to the manufacturer's specifications.
2. Reinstall Components: Reinstall all previously removed components, paying close attention to proper placement and torque specifications.
3. Prime the Oil System: Before starting the engine, ensure the oil system is properly primed.
4. Start the Engine: Start the engine and check for leaks and proper operation. Listen carefully for any unusual noises.
IV. Important Considerations:
* Precision: This process requires precision and accuracy. Inaccurate work can lead to engine damage.
* Cleanliness: Maintain a clean workspace to prevent contaminants from entering the engine.
* Torque Specifications: Always follow the manufacturer's torque specifications for all bolts and nuts.
* Safety: Always use appropriate safety precautions, including eye protection and gloves.
This is a simplified overview. A detailed, step-by-step guide with illustrations is crucial for successful completion. Consult a reliable repair manual specific to your Chevy 350 engine. Improperly performing this job can result in serious engine damage. If you lack experience, seek professional help.
