How do I break in my flat tappet camshaft and lifters?
Procedure
Breaking in an engine with a flat tappet camshaft is critical to its performance and long life. This mates the lifters to the cam lobes.
Most camshafts will come with specific break-in procedures. The following procedure could apply to any engine with a flat tappet cam. The specific instructions for your camshaft may vary slightly. Whenever possible, follow the manufacturer's instructions.
Installation Tips
- Always use new lifters when installing a new flat tappet camshaft.
- Apply a coat of Assembly/Break-In Lube to:
- Cam lobes,
- Bottom of the lifters, and
- Distributor gears.
- Use Break-In Oil.
- Do not "pump up" hydraulic lifters.
- Do not exceed Recommended Valve Spring Pressures.
- Performance engines using high valve spring pressures should use a lighter set of springs for the break-in procedure.
- If you have double or triple springs, remove the inner springs during the break-in procedure.
- If possible, break in the engine with the valve covers off. Watch the pushrods to make sure they are spinning.
- If they are not spinning, gently spin them with your fingers to start the process.
Procedure
- Install the Camshaft.
- Set the Valve Lash or Preload as recommended by the manufacturer.
- Prime the Oiling System.
- Set the Initial Ignition Timing.
- For carbureted engines, make sure fuel bowls are full and any air is bled from the fuel lines.
- Start the engine and immediately raise rpm to 3,000.
- Vary rpm between 1,500 and 3,000 for the next 20-30 minutes.
- Use a slow, steady acceleration/deceleration pattern.
- Shut down the engine and let it cool.
- Drain the oil and change the oil filter.
- This removes any metal particles from the break-in process.
- Refill the engine with break-in oil.
The initial break-in is now complete. After the next 500 miles of normal driving, change the oil and oil filter again.
- If you choose a synthetic oil, we recommend putting about 5,000 miles on the camshaft with conventional oil before switching.