#### DISASSEMBLY

Whether it is a single or dual overhead camshaft cylinder head, the disassembly procedure is relatively unchanged. One aspect to pay attention to is careful labeling of the parts on the dual camshaft cylinder head. There will be an intake camshaft and followers as well as an exhaust camshaft and followers and they must be labeled as such. In some cases, the components are identical and could easily be installed incorrectly. DO NOT MIX THEM UP! Determining which is which is very simple; the intake camshaft and components are on the same side of the head as was the intake manifold. Conversely, the exhaust camshaft and components are on the same side of the head as was the exhaust manifold.

Fig. 1: Exploded view of a valve, seal, spring, retainer and locks from an OHC cylinder head

Fig. 2: Example of a multi-valve cylinder head. Note how it has 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 equivalent) and a small magnet to disassemble the head.

Fig. 3: C-clamp type spring compressor and an OHC spring removal tool (center) for cup type followers

1. If not already removed, remove the camshaft(s) and/or followers. Mark their positions for assembly.

   Fig. 4: Most cup type follower cylinder heads retain the camshaft using bolt-on bearing caps

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

   NOTE: It is preferred to position the cylinder head gasket surface facing you with the valve springs facing the opposite direction and the head laying horizontal.

   Fig. 5: Position the OHC spring tool in the follower bore, then compress the spring with a C-clamp type tool

3. With the OHC spring removal adapter tool positioned inside of the follower bore, compress the valve spring using the C-clamp style valve spring compressor.
4. Remove the valve locks. A small magnetic tool or screwdriver will aid in removal.
5. Release the compressor tool and remove the spring assembly.
6. Withdraw the valve from the cylinder head.
7. If equipped, remove the valve seal.

   NOTE: Special valve seal removal tools are available. Regular or needlenose type pliers, if used with care, will work just as well. If using ordinary pliers, be sure not to damage the follower bore. The follower and its bore are machined to close tolerances and any damage to the bore will effect this relationship.

8. If equipped, remove the valve spring shim. A small magnetic tool or screwdriver will aid in removal.
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. However, 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.

Fig. 6: Example of the shaft mounted rocker arms on some OHC heads

Fig. 7: Another example of the rocker arm type OHC head. This model uses a follower under the camshaft

1. If not already removed, remove the rocker arms and/or shafts and the camshaft. If applicable, also remove the hydraulic lash adjusters. Mark their positions for assembly.

   Fig. 8: Before the camshaft can be removed, all of the followers must first be removed . . .

   Fig. 9: . . . then the camshaft can be removed by sliding it out (shown), or unbolting a bearing cap (not shown)

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

   Fig. 10: Compress the valve spring . . .

   NOTE: Due to engine varnish, the retainer may stick to the valve locks. A gentle tap with a hammer may help to break it loose.

   Fig. 11: . . . then remove the valve locks from the valve stem and spring retainer

4. Remove the valve locks from the valve tip and/or retainer. A small magnet may help in removing the small locks.
5. Lift the valve spring, tool and all, off of the valve stem.

   Fig. 12: Remove the valve spring and retainer from the cylinder head

6. If equipped, remove the valve seal. If the seal is difficult to remove with the valve in place, try removing the valve first, then the seal. Follow the steps below for valve removal.

   Fig. 13: Remove the valve seal from the guide. Some gentle prying or pliers may help to remove stubborn ones

7. Position the head to allow access for withdrawing the valve.

   NOTE: Cylinder heads that have seen a lot of miles and/or abuse may have mushroomed the valve lock grove and/or tip, causing difficulty in removal of the valve. If this has happened, use a metal file to carefully remove the high spots around the lock grooves and/or tip. Only file it enough to allow removal.

8. Remove the valve from the cylinder head.

   Fig. 14: All aluminum and some cast iron heads will have these valve spring shims. Remove all of them as well

9. If equipped, remove the valve spring shim. A small magnetic tool or screwdriver will aid in removal.
10. Repeat Steps 3 though 9 until all of the valves have been removed.