Flex-Hone® Applications: Deglazing Cylinder Walls

Deglazing removes the polished surface, or glaze, from the walls of engine cylinders so that piston rings seat properly, friction is reduced, and proper lubrication is achieved. In gasoline and diesel engines, the reciprocating or up-and-down movement of pistons causes the piston rings to rub against cylinder walls. Over time, this mechanical motion polishes the walls to such a smooth finish that the piston rings can’t provide a tight enough seal. Glazed cylinder walls can also cause lubrication problems since engine oil won’t adhere properly to a mirror-smooth surface. Fortunately, the Flex-Hone® tool from Brush Research Manufacturing (BRM) provides a cost-effective solution to these potential engine problems.

Deglazing and Piston Rings

End gap is a critical measurement when fitting new piston rings. If the end or ring gap is too small, the piston rings can bend or break. If the end gap is too large, engine cylinder compression will suffer and the engine may begin to burn more oil. Before installing new piston rings then, engine mechanics use cylinder hones to true worn cylinders and break the glaze. The Flex-Hone tool from Brush Research produces a controlled surface condition and creates a cross-hatched pattern that’s extremely efficient at creating grooves for oil retention. By contrast, conventional-type rigid hones produce unidirectional or uneven grooves that may interfere with optimum lubrication. Flexible ball hones from Brush Research also use a low-temperature abrading process to produce a long-wearing surface.

Is Cylinder Honing Recommended?

If you’re ever unsure whether cylinder honing is right for your chrome or cast-iron piston rings, check the ring manufacturer’s recommendations. Typically, this information accompanies the installation instructions. An old issue of Car Craft magazine once called engine honing a “complete waste of time”, but we disagree. As ddude2cu in Nissan Forums explained, it’s “vital” to deglaze a cylinder “if you don't bore it out”, and to ensure proper piston seating. When Joel4JC, a Nisan Forum newbie continued to disagree, dude2cu student cited a textbook – and invited the cylinder honing skeptic to “find out by trial and error”. Learning the hard way isn’t something we recommend if you’re serious about engine performance, so we hope you’ll remember the facts in the face of opinion.