RAM 2500 Van V8-5.2L VIN Y (1998)
Refacing Valve Seats
CAUTION: DO NOT un-shroud valves during valve seat refacing.
1. When refacing valve seats, it is important that the correct size valve guide pilot be used for reseating stones. A true and complete surface must be
obtained.
2. Measure the concentricity of valve seat using a dial indicator. Total runout should not exceed 0.051 mm (0.002 inch) total indicator reading.
3. Inspect the valve seat with Prussian blue to determine where the valve contacts the seat. To do this, coat valve seat LIGHTLY with Prussian blue
then set valve in place. Rotate the valve with light pressure. If the blue is transferred to the center of valve face, contact is satisfactory. If the blue
is transferred to the top edge of valve face, lower valve seat with a 15° stone. If the blue is transferred to bottom edge of valve face raise valve seat
with a 60° stone.
4. When seat is properly positioned the width of intake seats should be 1.016-1.524 mm (0.040-0.060 inch). The width of the exhaust seats should be
1.524-2.032 mm (0.060-0.080 inch).
VALVE SPRING INSPECTION
Testing Valve Spring For Compressed Length
Whenever valves have been removed for inspection, reconditioning or replacement, valve springs should be tested. As an example the compression
length of the spring to be tested is 1-5/16 inch. Turn table of Universal Valve Spring Tester Tool until surface is in line with the 1-5/16 inch mark on
the threaded stud. Be sure the zero mark is to the front. Place spring over stud on the table and lift compressing lever to set tone device. Pull on torque
wrench until ping is heard. Take reading on torque wrench at this instant. Multiply this reading by 2. This will give the spring load at test length.
Fractional measurements are indicated on the table for finer adjustments. Refer to specifications to obtain specified height and allowable tensions.
Discard the springs that do not meet specifications.
