Nissan Frontier. Manual — part 717
CAMSHAFT
EM-57
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Measure the outer diameter of camshaft journal with a micrometer.
CAMSHAFT BRACKET INNER DIAMETER
• Tighten camshaft bracket bolts with the specified torque. Refer to
EM-54, "Removal and Installation"
.
• Measure inner diameter “A” of camshaft bracket with a bore gauge.
CAMSHAFT JOURNAL OIL CLEARANCE
• (Oil clearance) = (Camshaft bracket inner diameter) – (Camshaft journal diameter)
• If out of the standard, replace either or both camshaft and cylinder head.
NOTE:
Camshaft brackets cannot be replaced as single parts, because they are machined together with cylinder
head. Replace whole cylinder head assembly.
Camshaft End Play
1. Install camshaft in cylinder head. Refer to
EM-54, "Removal and Installation"
2. Install a dial indicator in thrust direction on front end of camshaft.
Measure the camshaft end play on the dial indicator when cam-
shaft is moved forward/backward (in direction to axis).
Standard:
No. 1
: 27.935 - 27.955 mm (1.0998 - 1.1006 in)
No. 2, 3, 4, 5 : 23.435 - 23.455 mm (0.9226 - 0.9234 in)
PBIC0040E
Standard:
No. 1
: 28.000 - 28.021 mm (1.1024 - 1.1032 in)
No. 2, 3, 4, 5 : 23.500 - 23.521 mm (0.9252 - 0.9260 in)
PBIC1645E
Standard
: 0.045 - 0.086 mm (0.0018 - 0.0034 in)
Standard
: 0.115 - 0.188 mm (0.0045 - 0.0074 in)
PBIC2446E
EM-58
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CAMSHAFT
• Measure the following parts if out of the standard.
- Dimension “A” for camshaft No. 1 journal
- Dimension “B” for cylinder head No. 1 journal bearing
• Use the standards above, and then replace camshaft and/or
cylinder head, if necessary.
Camshaft Sprocket Runout
1. Put V-block on precise flat table, and support No. 2 and 5 journals of camshaft.
CAUTION:
Do not support No. 1 journal (on the side of camshaft sprocket) because it has a different diameter
from the other four locations.
2. Measure the camshaft sprocket runout with a dial indicator.
(Total indicator reading)
• If it exceeds the limit, replace camshaft sprocket.
Valve Lifter
Check if surface of valve lifter has any wear or cracks.
• If anything above is found, replace valve lifter. Refer to
Valve Lifter Clearance
VALVE LIFTER OUTER DIAMETER
• Measure the outer diameter of valve lifter with a micrometer.
VALVE LIFTER HOLE DIAMETER
Standard
: 25.800 - 25.848 mm (1.0157 - 1.0176 in)
Standard
: 25.660 - 25.685 mm (1.0102 - 1.0112 in)
KBIA2426J
Limit
: 0.15 mm (0.0059 in)
PBIC0930E
KBIA0182E
Standard
: 33.965 - 33.980 mm (1.3372 - 1.3378 in)
JEM798G
CAMSHAFT
EM-59
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Measure the diameter of valve lifter hole of cylinder head with an
inside micrometer.
VALVE LIFTER CLEARANCE
• (Valve lifter clearance) = (Valve lifter hole diameter) – (Valve lifter outer diameter)
• If out of the standard, referring to the standard of valve lifter outer diameter and valve lifter hole diameter,
replace either or both valve lifter and cylinder head.
INSTALLATION
1. Install valve lifters.
• Install them in the original positions.
2. Install camshafts.
• Distinction between intake and exhaust camshafts is per-
formed with the different shapes of rear end.
• Install camshafts so that camshaft dowel pins on the front side
are positioned as shown.
3. Install camshaft brackets with the following procedure:
a. Remove foreign material completely from camshaft bracket backside and from cylinder head installation
face.
Standard
: 34.000 - 34.021 mm (1.3386 - 1.3394 in)
PBIC0043E
Standard
: 0.020 - 0.056 mm (0.0008 - 0.0022 in)
Intake
: Signal plate shape for camshaft posi-
tion sensor (PHASE)
Exhaust : Cone end shape
KBIA0246E
KBIA0051E
EM-60
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CAMSHAFT
b. Install camshaft brackets (No. 2 to 5) aligning the identification
marks on upper surface as shown.
NOTE:
Install so that identification mark can be correctly read when
viewed from the exhaust side.
c.
Install camshaft bracket (No. 1) with the following procedure:
i.
Apply liquid gasket to camshaft bracket (No. 1) as shown.
Use Genuine RTV Silicone Sealant or equivalent. Refer to
GI-21, "Recommended Chemical Products and Sealants"
.
CAUTION:
After installation, be sure to wipe off any excessive liquid
gasket leaking from part (A).
ii.
Apply liquid gasket to camshaft bracket (No. 1) contact surface
on the front cover backside.
Use Genuine RTV Silicone Sealant or equivalent. Refer to
GI-21, "Recommended Chemical Products and Sealants"
.
• Apply liquid gasket to the outside of bolt hole on front cover.
iii. Locate camshaft bracket (No. 1) near installation position, and
install it without disturbing the liquid gasket applied to the sur-
faces.
4. Tighten bolts of camshaft brackets in the following steps, in numerical order as shown.
SBIA0256E
PBIC2579E
SBIA0258E
PBIC2746E
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