Valve Guides

Having proper valve guides installed in your cylinder head and with the proper clearances, along with high quality valve stem seals, ensures leak-free operation. This prevents excess oil consumption as well visible blue smoke while your vehicle is accelerating.

Proper sealing between the valve seat in the cylinder head and the head of the valve is critical to maximize power and performance in your engine. The proper installation of valve guides ensures that the valve will be centered in the head, and with the proper valve guide clearance, will reduce excess noise caused by too much guide-to-valve clearance.

Determining when to replace valve guides can be done with some simple observations and tests. Possible symptoms of worn cylinder head valve guides include excessive oil consumption as well as blue smoke under vehicle acceleration (which can be either worn guides or piston rings). Checking the spark plugs for sediment that is grayish or brownish on one side can also be a sign of a worn valve guide(s). With the cylinder head off the engine, check the clearance between a valve stem and the guide. Too much side-to-side movement or "wiggle" of the valve within the guide points to excessive wear. However, if the valve stem has no side-to-side movement or wiggle inside the guide, it's too tight, requiring valve guides replacement. If after coating the valve stem lightly with motor oil and the wiggle is gone, the clearance is correct. If the valve is still wiggling with a coating of oil within the guide, the clearance is too great, also requiring replacement.

Depending on the cylinder head type and material, the steps to replacing valve guides can vary and change. It is important to research the specific instructions for your application before installation is performed or get help from a machine shop if you don't fully understand the installation process. In many applications, after removing the old engine valve guides, heating up the cylinder head in a cleaning oven and cooling the automotive valve guides in a freezer will help with reducing clearance issues during installation, in addition to using lubrication. The direction valve guides are installed is also dependent on the specific application. Cutting the seat counter bores with a cutting tool kit may also be necessary in some applications in preparation for guide installation.