Tech Tip: Piston Ring Installation Tips – UnderhoodService

Tech Tip: Piston Ring Installation Tips

File fit ring sets require filing of the top and 2nd rings to achieve the correct end gap. To properly measure the ring gap, the ring should be square in the bore one inch down from the deck.

File fit ring sets require filing of the top and 2nd rings to achieve the correct end gap. To properly measure the ring gap, the ring should be square in the bore one inch down from the deck.

Measure the ring end gap with a feeler gauge or equivalent device. Calculate the recommended ring end gap from the chart (Figure 1).



figure 1 - installation chart for manley piston rings. A proper ring gap filing tool must be used. Ring filing should be done in an inward direction and square to the sides of the ring. Be sure to de-burr all edges after filing.



Correct ring installation is critical. Only Manley rings, top ring has a shiny gray edge. When the top and 2nd ring has a dot, install dot side up. Unmarked top rings with an inner bevel install with bevel up. Unmarked 2nd rings with inner bevel install with bevel down.

Narrow rings (1.0/1.2mm) that aren’t marked or beveled can be installed with either side up. Do not overlap the ends of the oil ring expander. See orientation diagram (Figure 2).



figure 2 - do not overlap the ends of the oil ring expander. Ring to piston groove back clearance should be a minimum of .005˝ deeper than the radial wall dimension of the piston ring. The piston ring should not stick out of the groove by any amount. Ring groove side clearance should be a minimum of .0015˝ to a maximum of .0030˝.



When included, the oil rail supports are installed on the bottom of the oil ring groove underneath the oil rail on Manley rings. The oil rail supports feature a special protruding dimple to prevent rotation of the oil rail support and the protruding dimple should be installed facing the bottom of the piston.

This dimple should be positioned directly in line with the piston pin. Keep the oil rail support gap 90° from the piston pin bore opening.



Tech Tip courtesy of Manley Performance Products.

You May Also Like

Diagnosing Intercooler Boost Trouble Code P0299

The criteria for setting the code is very basic.

A code P0299 for lower- than-normal boost can be one of the most challenging DTCs to resolve. You might think it is a code for a leak, but it could be more than a leak. The criteria for setting the code is very basic. The engine management system is looking at the desired boost pressure and the actual boost pressure, if the actual and desired do not match for the conditions. 

Honda Electronic Throttle Body Service Tips

Using care and following OEM procedures will help you to avoid unnecessary parts replacement and comebacks.

Why Alternators Are Subject To Ripple Voltage

The alternator produces an AC current that must be converted into DC current by way of a rectifier.

Belts and Pulley Alignment

A misalignment of the plane of the belt can occur when a pulley is not parallel to the other pulleys on the belt drive system.

Diagnosing Misfires

What if there are no codes and a misfire is intermittent? This is where it gets complicated.

Other Posts

Lifter Deactivation

The area of contact between the lifters and cam lobes is the highest loaded surface inside an engine.

Alternator Testing For No Charge Conditions

Many alternator problems turn out to be nothing more than a bad connection at the alternator or a bad wiring harness.

Understanding Coolants

All-season coolant used inorganic acid technology and worked great for almost 30 years.

Ignition System Do’s and Don’ts

Why do ignition systems give technicians problems when diagnosing ignition-related misfires? The answer is that some technicians use tests that might give inconclusive results or do damage to the coil or drivers inside a module.