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Disassembly

OHV Heads
  1. Remove the rocker arms and/or shafts.
  2. Position the head so that the springs are easily accessed.

    Valve spring compressor tool

  3. Use a valve spring compressor tool, and relieve spring tension from the retainer.

    A small magnet used in removal of valve locks

    Valve locks (keepers)

  4. Remove the valve locks from the valve tip and/or retainer.
  5. Release the spring compressor and remove the valve spring.

    O-ring type seal

    Umbrella/positive type seal

  6. Remove the valve seal.

    Removing exhaust valve

  7. Position the head to allow access for withdrawing the valve.
  8. Remove the valve from the cylinder head.
  9. If equipped, remove the valve spring cup.
OHC Cylinder Heads

Exploded view of a valve, seal, spring, retainer and locks from an OHC cylinder head

Example of a multi-valve cylinder head with 2 intake and 2 exhaust valve ports

Cup Type Camshaft Followers

Most cylinder heads with cup type camshaft followers will have the valve spring, retainer and locks recessed within the follower’s bore. You will need a C-clamp style valve spring compressor tool, an OHC spring removal tool (or its equivalent) as well as a small magnet to disassemble the head.

C-clamp type spring compressor and an OHC spring removal tool (center) for cup type followers

  1. Remove the camshaft(s) and/or followers. Mark for reassembly.

    Cup type bolt-on bearing caps

  2. Position the cylinder head to allow use of a C-clamp style valve spring compressor tool.

    OHC spring tool and C-clamp

  3. Position the OHC spring removal adapter tool inside of the follower bore, then compress the valve spring using the C-clamp style valve spring compressor.
  4. Remove the valve locks.
  5. Release the compressor tool and remove the spring assembly.

    NOTE: Check for burrs or high spots on the valve tip and valve lock area. Use a metal file to remove burrs before removing the valve from the head.

  6. Remove the valve from the cylinder head.
  7. Remove the valve seal.
  8. If equipped, remove the valve spring shim.
  9. Repeat Steps 3 through 8 until all of the valves have been removed.
Rocker Arm Type Camshaft Followers

Most cylinder heads with rocker arm-type camshaft followers are easily disassembled using a standard valve spring compressor. Certain models may not have enough open space around the spring for the standard tool and may require you to use a C-clamp style compressor tool instead.

OHC shaft mounted rocker arms

OHC rocker arm type head

  1. Removed the rocker arms and/or shafts and the camshaft.
  2. If applicable remove the hydraulic lash adjusters. Mark for reassembly.

    Remove the followers

    . . . then the camshaft can be removed by sliding it out (shown), or unbolting a bearing cap (not shown)

  3. Position the cylinder head to allow access to the valve spring.
  4. Use a valve spring compressor tool to relieve the spring tension from the retainer.

    Compressing the valve spring

    Removing the valve locks

  5. Remove the valve locks from the valve tip and/or retainer.
  6. Release the spring compressor and remove the valve spring off of the valve stem.

    Valve spring and retainer

  7. Remove the valve seal.

    Removing valve seal from the guide.

  8. Position the head to allow access for removing the valve.

    NOTE: Some cylinder heads may have mushroomed valve lock grooves and/or valve tips, making it difficult to remove valves. If so, use a metal file to carefully remove the high spots around the lock grooves and/or tip. File enough to make valve removal possible.

  9. Remove the valve from the cylinder head.

    Valve spring shim

  10. If equipped, remove the valve spring shim.
  11. Repeat Steps 3 though 9 until all of the valves have been removed

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