low oil pressure FIAT 127 1973 1.G Workshop Manual

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Ignition distributor clamp nut 11 1.5
Oil pump to crankcase bolts 13 1.8
Cylinder head outlet pipe bolt 16 2.2
Water pump/alternator drive pulley nut 101 14
Alternator bracket to crankcase bolt 20 2.8
Alternator to lower bracket bolt 36 5
Cylinder head upper bracket bolt 20 2.8
Alternator to upper bracket nut 36 5
Upper bracket securing bolt 13 1.8
Oil pressure switch 24 3.3
Coolant temperature switch 36 5
Spark plug 27 3.8

Sport models only
Engine
Flexible mounting to body (engine side) 65 9.0
Flexible mounting support (engine side to body)
18 2.5
Flexible mounting upper support to gearbox 18 2.5
Engine crossmember to body 18 2.5
Flexible mounting support nut (gearbox side) 18 2.5
Flexible mounting support bolt to body
(gearbox LH side) 65 9.0
Steering and suspension
Steering wheel retaining nut 22 3.0
Front wheel bearing ring nut 44 6.0
Front wheel hub nut 160 22.0
Roadwheel bolts 64 8.8
Front suspension track control arm to body 20 2.7
Front suspension balljoint to hub carrier 40 5.5
Rear wheel hub nut 160 22
Transmission
Starter motor bolt to bellhousing lower support 18 2.5
Gear selector shaft nut 18 2.5
Upper gear lever relay lever 22 3.0
Idler support securing nut 18 2.5
Differential case flange to gearbox housing 18 2.5

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3.8 The half thrust washers are fitted each side of
the
centre bearing


3.9 Oil the bearings and crankshaft journals…





3.10 … and then fit the crankshaft into the crankca se 12 Refit the main bearing cap bolts and screw
them up fingertight. Spin the crankshaft and, if
all is well, tighten the bolts to the specified
torque load and turn the crankshaft again to
check freedom of rotation (photo).
13 Measure the crankshaft endfloat with feeler
gauges. If this exceeds the specified tolerance,
oversize thrust washers will have to be fitted.
Pision rings - refitting
14 Follow the procedure given in Chapter 1,
Section 42.
Pistons and connecting rods–reassembly
15 Follow the procedure given in Chapter 1,
Section 43 (photo).
Pistons – refitting
16 Follow the procedure given in Chapter 1,
Section 44.
17 Note that the connecting rods in the 1049 cc
engine have two oil jet holes leading from the
big-end bearing (photo).
18 When the piston is correctly fitted it will have

the valve depressions adjacent to the side of the
block with the cylinder head studs in (photo). C
onnecting rods to crankshaft-
r
eassembly
19 Follow the procedure given in Chapter 1,
Section 45.
20 Torque load the big-end cap nuts to the
reading quoted in the Specifications of this
Chapter 13 - it is different from the value quoted
for the 903 cc engine (photo).
Oil pump - reassembly
21 The oil pump fitted to the 1049 cc engine is a
Hobourn-Eaton rotor type of pump which is quite
different from the gear pump fitted to the 903 cc
engine. It consists of a four lobed rotor rotating
in a five slotted outer rotor which is mounted
eccentrically to the inner rotor. As the inner roto r
rotates the outer rotor is driven round, and the
spaces between the lobes on the inner rotor and
the slots in the outer rotor increase and
decrease once per revolution. The increasing
spaces are connected to the pump inlet and
cause oil to be drawn into the pump. The
decreasing spaces connect with the pump outlet
through which the oil is forced to feed the
engine. A springloaded relief valve in the outlet
of the pump vents excessive oil pressure into
the sump. The efficiency of the pump depends

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3.25 …and the inner to outer rotor clearance 3.27A Fit the oil pump pressure relief valve plunge r and
spring…


3.27B …followed by the retainer plate and circlip 3.28 Refit the pump lower half body


3.29 Fit the oil pump to the crankcase 3.30 The oil tube is secured by a bracket to the ce ntre main
bearing cap with a bolt and washer

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3.32 Fitting the crankshaft seal and carrier at fly wheel
and… 3.33 …and at the timing cover end



3.34 The timing indicator bracket is located behind the two
top bolts of the seal carrier 3.36 Fit the sump to the crankcase

on fine clearances and these should be checked
during assembly.
22 Fit the outer rotor to the pump body and then
fit the inner rotor (photos).
23 Lay an accurate straight edge across the
faces of the rotors and pump body and measure
the clearance with feeler gauges (photo).
24 Insert a feeler gauge between the outer rotor
and the pump body to measure the clearance
(photo).
25 Similarly insert a feeler gauge between the
inner rotor lobe tip and the outer rotor to
measure the clearance between the two (photo).

26 Compare the clearances with the tolerances
quoted in the Specifications to this Chapter. Any
excessive clearance could result in low oil
pressure, and as the inner and outer rotors are
matched pairs the only solution is a new or
reconditioned pump assembly. 27 Fit the oil pressure relief valve plunger to th
e
pump body followed in turn by the spring,
retainer plate and circlip (photos).
28 Lubricate the rotors with clean engine oil and
refit the pump lower half body and strainer
(photo).
29 With a new gasket, fit the assembled oil
pump to the crankcase block and secure with
the two long bolts (photo). Tighten to the
specified torque load.
30 Fit the oil tube to the crankcase securing it by
its bracket to the centre main bearing cap with
its retaining bolt. Tighten to the specified torque
load (photo).
Craknshaft oil seals and carriers-refitting
31 Clean the flywheel mounting spigot on the
end of the crankshaft and lubricate the
crankshaft seal with clean engine oil. Fit a new
gasket.