Valve Guide Replacement & Machining

As part of our cylinder head reconditioning process, we assess the condition of the existing valve guides to determine the clearance between the valve stems and the valve guides.

If the clearance is excessive this can cause a number of issues, including excessive oil burning and damage to the valves and valve seats. If this is the case, the valve guides will need to be replaced.

For alloy and some cast iron heads, they will have removable valve guides, which we will replace with new ones, or in the case of many cast iron cylinder heads, the guide hole is machined straight into the casting from the factory and the only way to fix them is to bore them out and fit new replaceable valve guides, that can be easily replaced in the future. In both cases the valve guides are honed to achieve the exact clearance required.