During this "How To" guide, I will try to describe the procedure for removing and refitting the cylinder head of a CVH. You may skip the Removal of the head and go for the Refitting by clicking the link below.

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Removal

Tool List:

• A decent Socket set with 10/13/15/19/41mm sockets.
• A decent 19mm ring spanner.
• A breaker bar or long handled ratchet.
• Torque Wrench.
• Suitable container for the reusable parts.

1. Make sure you have all the correct tools as listed above.
2. Drain the coolant system.
3. Disconnect the battery + terminal.
4. Disconnect and remove the air filer box.
5. Disconnect the PCV (Progressive Crankcase breather Valve) from the rocker cover.
6. Disconnect any ancillary connections/leads from the head.
7. Disconnect any earth straps from the head.
8. Mark up the HT leads with their cylinder number, then unplug from the spark plugs.
9. Remove the coil pack HT lead.
10. Remove the spark plugs.
11. Disconnect the fuel lines from the carburetor, suitably plugging them when done.
12. Remove the coolant hoses.
13. Disconnect the brake servo vacuum connection from the carburetor.
14. Undo the bolts connecting the exhaust manifold to the downpipe, drop the downpipe leaving the manifold bolted to the head. Leaving both manifolds on the head helps when we come to lifting the head off the block, as they provide a good holding for lifting and levering.
15. Remove the upper timing belt cover.
16. Remove the crank case breather pipe from the rocker cover.
17. Remove the timing belt as described in the previous section. Click here.
18. Remove the lower timing belt cover.
19. Undo the 9 rocker cover retaining bolts.
20. Remove the rocker cover.
21. You will see 10 head retaining bolts located as pictured below:
    
    
    
22. WARNING! These bolts must be removed following the procedure detailed in the next few steps. Failure to do so may result in head warping. Also note that these bolts can be very tight, care should be taken whilst removing.
23. The diagram below illustrates the order in which the head bolts must be undone:
    
    
    
24. Starting with bolt #1, using a breaker bar and a 15mm socket, break the tightness of the bolt and move on to the next.
25. Once all the bolts have been "Broken", rotate them each through 90 degrees at a time, still following the order above.
26. Once the bolts have been removed, we're ready to remove the head from the block. WARNING! Don't be tempted to knock the head to the side, the head is located on 2 dowels, so any knock side on could cause damage.
27. Using the two manifolds as handles, rock the head lightly from pulley end to dizzy end to break the seal of the gasket, then carefully lift the head off the block, and place it on a clean dry cloth on an even surface.
28. You have now successfully separated the head and the block. Now clean up both surfaces and keep them covered to avoid damage. I like to place the rocker cover back over the head, to avoid any dust entering the valve train. Remember to keep the old head gasket for comparison to the new one.

Refitting

1. Thoroughly clean the surfaces of the head and block, removing any traces of dirt, oil or grease.
2. Place the two head locating dowels in their respective holes.
3. Place the new head gasket on to the head. WARNING! Check that the head gasket is on the correct way. If it is marked with "OBEN-TOP" this face should be upwards, with the writing to the back of the block. If it isn't marked, check that the oil and water galleries match up, and that the diagonal elongated water gallery at the back of the block face if covered correctly.
4. Place the head back on to the block, being careful and making sure that it locates correctly on the dowels.
5. Place all 10 head bolts in to their respective holes, and hand tighten them (Without using a socket or spanner)
6. Set your torque wrench to 25Nm and tighten each bolt following the order as illustrated below:
   
   
   
7. Once they have all been tightened, set your torque wrench to 55Nm, and repeat the process.
8. Now, take some marker paint or Tip-Ex and mark an edge of each bolt head. This is to ensure that the next step is carried out correctly.
9. Take your breaker bar and a 15mm socket, and tighten each bolt in order through 90 degrees. WARNING! I found this to be very strenuous.
10. Rotate the bolts through a further 90 degrees following the order above. WARNING! I found this to be very very strenuous. The head and block have now been reunited.
11. Refit the timing belt as described in the previous section. Click here.
12. Replace the lower and upper timing belt covers.
13. Replace the crank case breather pipe ont to the rocker cover.
14. Re-fit the exhaust manifold to the downpipe.
15. Replace the brake servo vacuum connection to the carburetor.
16. Replace the coolant hoses.
17. Replace the fuel lines to the carburetor.
18. Replace the spark plugs.
19. Re-connect the HT Leads.
20. Re-connect the PCV.
21. Replace the air filter box.
22. Re-fill the coolant system.
23. Re-connect the battery.
24. Don't forget before starting the engine to prime the oil pump if the oil has also been replaced.

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