AJ16 Engine Service Manual
FAULT DIAGNOSIS
3.1 Introduction
The following diagnostic procedures are provided to assist properly qualified persons to identify and rectify the faults
relating to the engine which are most likely to encountered. Reference is made to the Electrical Diagnostic Manual
(EDM), which should be consulted where necessary. Faults related to the cooling system are dealt with in Section 4.1
and to the fuel system in Section 5.1 in the appropriate Vehicle Service Manual (VSM).
3.2 Diagnostic Procedures
(fails to rotate)
I Engine rotates but 0 I will not fire
I
i
/Overheating
Overheating at tick-
Too cold
Loss of coolant Possible
Cause
Battery leads loose or ter
- minals corroded
Battery discharged
Starter motor inoperative
Starter motor speed too
low
Faulty ignition system
Fuel system defect
Oil requires changing
Worn crankshaft journals
Excessive crankshaft
end- float
Worn main bearing shells
Worn oil pump Oil pressure relief valve stick
- ing open
Oil pressure relief valve
spring too weak
Insufficient oil in oil pan
Engine overheating
Faulty gauge or sensor
Incorrect grade oil (viscosity
too low)
Water in oil Check
Check the condition of the
leads and terminals
Check condition of battery
with hydrometer
If the lights dim when ignition
switch is operated, the starter
may be jammed in starter
ring.
Check for loose and dirty con
- nections to the starter motor
Check battery leads and ter
- minals
Check state of battery charge
Refer to EDM
Remove the spark plugs
Check oil level and color
Listen for rumble or knock
Fit dial gauge and measure
Listen for rumble
Remove oil pump and check
the clearances
Remove valve and check for
sticking
Remove spring and check
spring rates
Check oil level
Refer to EDM
Check oil viscosity
Checkoil level and check if oil
is a milky white color
Check for leaking head gasket Remedy
Clean and tighten as necess
-
ary
Charge or renew battery as
necessary
Remove starter motor, free
off pinion and refit
Clean and tighten connec
- tions
Clean and tighten terminals
Charge or renew battery
as necessary
Rectify as required
Clean and re
-gap the spark
plugs, renew if worn out
Refer to Fuel System fault
finding in Section
5.1, VSM
Refer to Section
4.1, VSM
Refer to Section
4.1, VSM
Refer to Section
4.1, VSM
Refer to Section
4.1, VSM
Change oil and filter
Renew crankshaft
Renew thrust washers
Check crankshaft journals for
wear and renew shells
Renew oil pump
Renew valve
Renew spring
lop-up as required
Refer to Overheating fault
finding in Section
4.1, VSM
Rectify as required
Renew oil and filter
Renew oil and filter
Renew head gasket
Issue 1 August 1994 3
AJ16 Engine Service Manual
4.24 Auxiliary Shaft, Renew
SRO 12.10.30
Remove the timing cover.
. Remove the pulley woodruff key and remove the oil seal
spacer from the crankshaft.
. Remove the flanged bolts (3 Fig. 1) securing the tensioner
pedestal.
Remove the pedestal / tensioner assembly and chain
damper (1 Fig. 1).
. Remove the tensioner pivot pin (2 Fig. 1) and remove the
tensioner from the pedestal. Clean the pivot pin.
. Remove the flanged bolts (5 Fig. 1) securing the upper
static damper. Remove the damper (4 Fig. 1) and upper
timing chain (6 Fig. 1).
Remove the bolts (11 Fig. 1) securing the chain tensioner
and remove the assembly (17 Fig. 1).
Remove the power assisted steering pump assembly, see
Section 10 in the appropriate Vehicle Service manual
. Remove the pump drive coupling.
. Remove the flanged bolt (1 Fig.2) and the drive-plate (2 Fig. 2).
Using Service Tool JD 118, remove the auxiliary shaft rear
oil seal (3 Fig. 2) from its housing.
. Using right-angled snap-ring pliers remove the snap-ring (5 Fig. 2) securing the drive shaft (4 Fig.2).
. Lift the timing chain (8 Fig. 1) from the sprocket (7 Fig. 11, remove the shaft / sprocket assembly and retrieve the
thrust washer.
. Clean all component parts and checkfor wear or damage.
Renew worn or damaged parts as necessary. Clean the auxiliary bearing housing.
. Check for wear and if necessarychangethe auxiliaryshaft bushes.
. Refit the housing with new gasket. Fit and tighten the se-
curing bolts.
. Lubricate the shaft and refit the to the housing, engaging
the chain with the gear as it is fitted. Lubricate and fit the
thrust washer and secure with the snap-ring.
. Renew the auxiliary shaft rear oil seal, see Section 4.25.
. Refitthe power assisted steering pump assembly, see Sec-
. Refit the lower chain tensioner, see Section 4.22.
Refit the upper chain tensioner, see Section 4.21.
. Renew the oil seal (1 Fig. 3) and refit the timing cover.
tion
10 in
the appropriate Vehicle Service manual.
Fig. 1
Fig. 2
Fig. 3
Issue 1 August 1994 44
