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Acura RL. Manual - part 422

Fig. 112: Compressing Spring
Courtesy of AMERICAN HONDA MOTOR CO., INC.

4. Remove the special tool, then remove the valve retainer, valve spring, and valve.

5. Install the valve guide seal remover (A).

Fig. 113: Identifying Valve Guide Seal Remover
Courtesy of AMERICAN HONDA MOTOR CO., INC.

6. Remove the valve seal.

2007 Acura RL

2005-08 ENGINE Cylinder Head - RL

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Fig. 114: Removing Valve Seal
Courtesy of AMERICAN HONDA MOTOR CO., INC.

VALVE INSPECTION

1. Remove the valves (see VALVE, SPRING, AND VALVE SEAL REMOVAL ).

2. Measure the valve in these areas.

Intake Valve Dimensions

A Standard (New): 35.90-36.10 mm (1.413-1.421 in.)

B Standard (New): 116.55-117.15 mm (4.589-4.612 in.)

C Standard (New): 5.485-5.495 mm (0.2159-0.2163 in.)

C Service Limit: 5.455 mm (0.2148 in.)

Exhaust Valve Dimensions

A Standard (New): 29.90-30.10 mm (1.177-1.185 in.)

B Standard (New): 113.90-114.50 mm (4.484-4.508 in.)

C Standard (New): 5.450-5.460 mm (0.2146-0.2150 in.)

C Service Limit: 5.420 mm (0.2134 in.)

Fig. 115: Identifying Valve Dimensions
Courtesy of AMERICAN HONDA MOTOR CO., INC.

VALVE STEM-TO-GUIDE CLEARANCE INSPECTION

1. Remove the valves (see VALVE, SPRING, AND VALVE SEAL REMOVAL ).

2. Slide the valve out of its guide about 10 mm (0.39 in.), then measure the guide-to-stem clearance with

a dial indicator while rocking the stem in the direction of normal thrust (wobble method).



If the measurement exceeds the service limit, recheck it using a new valve.



If the measurement is now within the service limit, reassemble using a new valve.



If the measurement with a new valve still exceeds the service limit, go to step 3.

2007 Acura RL

2005-08 ENGINE Cylinder Head - RL

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Intake Valve Stem-to-Guide Clearance

Standard (New): 0.04-0.09 mm (0.002-0.004 in.)

Service Limit: 0.16 mm (0.006 in.)

Exhaust Valve Stem-to-Guide Clearance

Standard (New): 0.11-0.16 mm (0 004-0.006 in.)

Service Limit: 0.22 mm (0.009 in.)

Fig. 116: Measuring Valve Stem-To-Guide Clearance
Courtesy of AMERICAN HONDA MOTOR CO., INC.

3. Subtract the O.D. of the valve stem, measured with a micrometer, from the I.D. of the valve guide,

measured with an inside micrometer or ball gauge. Take the measurements in three places along the
valve stem and three places inside the valve guide. The difference between the largest guide
measurement and the smallest stem measurement should not exceed the service limit.

Intake Valve Stem-to-Guide Clearance

Standard (New): 0.020-0.045 mm (0.0008-0.0018 in.)

Service Limit: 0.08 mm (0.003 in.)

Exhaust Valve Stem-to-Guide Clearance

Standard (New): 0.055-0.080 mm (0.0022-0.0031 in.)

Service Limit: 0.11 mm (0.004 in.)

VALVE GUIDE REPLACEMENT

Special Tools Required



Valve guide driver, 5.5 mm 07742-0010100



Valve guide reamer, 5.5 mm 07HAH-PJ7A100

1. Inspect valve stem-to-guide clearance (see VALVE STEM-TO-GUIDE CLEARANCE

INSPECTION ).

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2005-08 ENGINE Cylinder Head - RL

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2. As illustrated, use a commercially available air-impact valve guide driver (A) modified to fit the

diameter of the valve guides. In most cases, the same procedure can be done using the special tool and
a conventional hammer.

Fig. 117: Identifying Valve Guide Dimension
Courtesy of AMERICAN HONDA MOTOR CO., INC.

3. Select the proper replacement guides, and chill them in the freezer section of a refrigerator for about

an hour.

4. Use a hot plate or oven to evenly heat the cylinder head to 300°F (150°C). Monitor the temperature

with a cooking thermometer. Do not get the head hotter than 300°F (150°C); excessive heat may
loosen the valve seats.

Fig. 118: Heating Cylinder Head
Courtesy of AMERICAN HONDA MOTOR CO., INC.

5. Working from the camshaft side, use the driver and an air hammer to drive the guide about 2 mm (0.1

in.) towards the combustion chamber. This will knock off some of the carbon and make removal
easier. Hold the air hammer directly in line with the valve guide to prevent damaging the driver. Wear
safety goggles or a face shield.

6. Turn the head over, and drive the guide out toward the camshaft side of the head.

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2005-08 ENGINE Cylinder Head - RL

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