Rocker Arm and Shaft Inspection

WARNING: This page is about a different car, the 2013 Acura MDX, 2012 Acura MDX, 2011 Acura MDX, and 2010 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.

Remove the rocker arm assembly (see ROCKER ARM ASSEMBLY REMOVAL ).
Disassemble the rocker arm assembly (see ROCKER ARM AND SHAFT DISASSEMBLY/REASSEMBLY ).
Measure the diameter of the shaft at the first rocker location.

Fig 1: Measuring Shaft Diameter
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Zero the gauge (A) to the shaft diameter.

Fig 2: Setting Gauge To Zero In Shaft Diameter
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Measure the inside diameter of the rocker arm, and check it for an out-of-round condition.
Intake Rocker Arm-to-Shaft Clearance

Standard (New): 0.015-0.046 mm (0.00059-0.00181 in)

Service Limit: 0.046 mm (0.00181 in)

Exhaust Rocker Arm-to-Shaft Clearance

Standard (New): 0.018-0.047 mm (0.00071-0.00185 in)

Service Limit: 0.047 mm (0.00185 in)

Fig 3: Measuring Inside Diameter Of Rocker Arm
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Repeat for all rockers and both shafts. If the clearance is over the limit, replace the rocker shaft and all over-tolerance rocker arms. If any intake rocker arm needs replacement, replace all rocker arms in that set (primary and secondary).
VTEC Rocker Arms
Inspect the rocker arm piston (A). Slide them into the rocker arms. If they do not move smoothly, replace the rocker arm set.
NOTE:
- Apply new engine oil to the rocker arm piston when reassembling.
- When removing rocker arm piston from the intake secondary rocker arm (B), carefully apply air pressure to the oil passage of the rocker arm.
Fig 4: Identifying Rocker Arm Piston And Intake Secondary Rocker Arm
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Reassemble the rocker arm assembly (see ROCKER ARM AND SHAFT DISASSEMBLY/REASSEMBLY ).
Install the rocker arm assembly (see CAMSHAFT, ROCKER ARM ASSEMBLY, CAMSHAFT SEAL, AND PULLEY INSTALLATION ).