Dodge ram truck 3500 1996 Service Manual page 1040

9 - 50 3.9L ENGINE
B R
C L E A N I N G
AND INSPECTION
(Continued)
If inner rotor measures 20.9 mm (0.825 in.) or less,
replace inner rotor and shaft assembly (Fig. 63).
Fig. 68 Measuring inner Rotor Thickness
Slide outer rotor into pump body. Press rotor to the
side with your fingers and measure clearance
between rotor and pump body (Fig. 64). I f clearance
is 0.356 mm (0.014 in.) or more, replace oil pump
assembly.
8 0 2 0 c d 6 f
' Fig. 64 Measuring Outer Rotor Ciearance in
Housing
Install inner rotor and shaft into pump body. I f
clearance between inner and outer rotors is 0.203
mm (0.008 in.) or more, replace shaft and both rotors
(Fig. 65).
Place a straightedge across the face of the pump,
between bolt holes. I f a feeler gauge of 0.102 mm
(0.004 in.) or more can be inserted between rotors
and the straightedge, replace pump assembly (Fig.
66).
Inspect oil pressure relief valve plunger for scoring
and free operation in its bore. Small marks may be
removed with 400-grit wet or dry sandpaper.
The relief valve spring has a free length of approx­
imately 49.5 mm (1.95 in.). The spring should test
between 19.5 and,20.5 pounds when compressed to
Fig. 65 Measuring Ciearance Between Rotors
8020cd71
Fig. 66 Measuring Ciearance Over Rotors
34 mm (1-11/32 in.). Replace spring that fails to meet
these specifications (Fig. 67).
I f oil pressure was low and pump is within specifi­
cations, inspect for worn engine bearings or other
reasons for oil pressure loss.
RN98
Fig. 67 Proper Installation of Retainer Cap