How to Rebuild a Cylinder Headby Dan Ferrell
Rebuilding the engine cylinder head on your car is an involved process that requires attention to detail. However, working systematically and focusing on one part of the job at a time, you can reach your goal in a matter of days. Depending on your knowledge and skills, it is better to work along with a more experienced person and follow the advice of a machine shop, which can work on the more precise job like head inspection and reconditioning.
Remove each rocker arm, valve, valve keeper, oil seal, valve spring and the rest of the valve assembly. Use a ratchet and socket, valve spring compressor and needle-nose pliers. Keep each valve and related parts in a properly labeled plastic bag. This will help you assemble the valve set in its exact same place unles you need to replace them.
Clean the head from old gasket material, carbon buildup, sludge and remaining deposits around the head, coolant and oil passages. Use a gasket scraper, solvent and a wire brush. If the head has hard buildup or sludge on it, it is a better idea to take it to a machine shop where it can be cleaned with special equipment.
Inspect the head for cracks and the valve seats for burns, cracks and pits. Also, check the camshaft for wear and damage, and make sure it is within the manufacturer specifications using a micrometer. You can find these specifications in the vehicle service manual for your particular engine. See Tips for more information.
Examine the head for warping using a straight edge and a feeler gauge. Lay the edge of the straightedge diagonally and lengthwise on the gasket surface of the head. You should get no more than 0.003 inches of gap between any two points within six inches below the straight edge. If necessary, send the head to the machine shop for resurfacing.
Check the rocker arms, pushrods, studs, valve guides and stems for wear and damage. If there is too much wear or damage on any of these parts, take the head to a machine shop where they can measure valve seats, valve guides and related components if necessary. The head might need rectification and new parts.
Assemble the head using new oil seals once all the parts have been thoroughly cleaned and inspected. Make sure to assemble each valve assembly in its corresponding place unless you are replacing parts with new ones.
- Consult your vehicle service manual for manufacturer specifications on your engine model. You can buy a manual at most auto parts stores or consult one for free at your local public library.
Items you will need
- Photo courtesy of Thekingofazle at Wikipedia.org.