AJ16 Engine Service Manual
4.3
SRO 12.29.48
1 Remove camshaft cover, see Section 4.2.
1 Rotate the engine as necessary to measurethevalve clear- ances between the heel of the cam and the cam follower
(Fig.
1). See Service Data in the Preliminary Pages for the
correct valve clearances.
1 Make a note of each clearance measurement.
1 Should the clearances be incorrect, proceed as follows:
1 Rotate the engine and set No. 1 cylinder at TDC using Ser- viceTool 18G 1433 (1 Fig. 2).
Push back the lock tabs (1 Fig. 3) from the camshaft
sprocket securing bolts (2 Fig. 3).
1 Slacken off the bolts and tab washers.
1 Remove the upper chain tensioner valve clamp bolt
(3 Fig. 3), remove the clamp (4 Fig. 3) and remove the
valve (5 Fig. 3).
1 Using a 3 mm Allen key, wind back the tensioner (turn
clockwise) until the snail engages in the park position.
1 Remove the tensioner housing securing bolt (7 Fig. 3) and
remove the tensioner assembly (8,9 Fig. 3).
1 Remove and discard the '0' ring (9 Fig. 3) and gasket (10 Fig. 3).
1 Remove the camshaft sprocket securing bolts/tab washers (1,2 Fig. 3) and remove the sprockets (1 1 Fig. 3).
1 Remove the cylinder head bolt from No. 2 cap, left-hand
camshaft (1 Fig. 4).
1 Remove the cap securing bolts from No. 2 cap, left-hand
cams haft.
. Remove No. 2 cap from the left-hand camshaft.
1 Fit spacer tool 18G 1435 (2 Fig. 4) to the head.
1 Fit and torque tighten the cylinder head bolt.
1 Repeat the procedure for Nos 3,4,5 and 6 caps, left-hand
camshaft
(3 Fig. 4).
1 Remove the cylinder head bolt from No. 7 cap, left-hand
camshaft.
1 Loosen in sequence the securing bolts from Nos 1 and 7 caps, until the left-hand camshaft is free. Lift the camshaft
from the cylinder head and fit spacer tool 18G 1435 to No. 7 cylinder head bolt position (5 Fig. 4). Fit and torque
tighten the bolt.
Valve Clearance, Check and Aa'just
1 Repeat the procedure for the right-hand camshaft.
CAUTION: The cylinder head bolts
MUST be renewed dur- ing assembly and torque tightened as de- scribed in Section 2.1, SPS Joint Control
System.
111 ...
Fig. 1
1
Fig. 2
Fig. 3
Fig. 4
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AJ16 Engine Service Manual
1 Move all the slack in the chain to the tensioner side.
1 Fit upper chain tensioner tool 18G 14361A (2 Fig. 1). Fit and
tighten the tool securing bolts (1 Fig. 1).
1 Tension the cam chain.
1 Remove the camshaft coupling (12 Fig.2) from the
sprocket (11 Fig. 2) and align the securing bolt holes. Fit
the bolts (2 Fig. 2) and tab washers (1 Fig. 2), tighten the
securing bolts and lock over the tabs.
1 Repeat the procedure for the other sprocket.
1 Slacken off the chain tensioner tool securing bolts
1 Remove the tensioner tool.
1 Clean the tensioner assembly and gasket faces.
= Fit a new housing gasket (10 Fig. 2). Fit and lubricate a
new ‘0’ ring (9 Fig. 2).
1 Fitthetensionerassembly (8,9 Fig. 2)tothecylinderhead.
Fit andtighten thetensioner assembly securing bolt (3 Fig.
2).
(1 Fig. 1).
1 Fit but do not tighten the valve clamp bolt.
1 Clean the valve assembly and fit new ‘0‘ rings (13 Fig. 2).
Lubricate the tensionervalve (5 Fig. 2). Using an Allen key,
release the tensioner, by turning the
Allen key anti-clock- wise.
1 Fit the tensioner valve (5 Fig. 2). Position the clamp (4 Fig. 2) over the valve.
1 Tighten the clamp bolt (3 Fig. 2).
1 Refit the camshaft cover, see Section 4.2. Fig.
1
I Fia. 2
Issue 1 August 1994 12
AJ16 Engine Service Manual
4.4 Cylinder Head Gasket, Renew
SRO 12.29.01
Drain the cooling system, see Section 4.1 and depressurize
the fuel system,see Section 5.1 (thesesections are in the ap- propriate Vehicle Service Manual). Disconnect the exhaust
system with the vehicle supported on axle stands. Remove
components as required for access to the cylinder head and
proceed as follows.
1 Rotate the engine to TDC No. 1 cylinder.
1 Remove the camshaft cover, see Section 4.2.
1 Push backthe lock tabs and remove the camshaft sprocket
securing bolts (2 Fig. 1). Remove the tab washers (1 Fig. 1).
1 Remove the upper chain tensioner valve clamp bolt (1 Fig. 2), remove the clamp (2 Fig. 2) and remove the
valve (3 Fig. 2).
1 Using a 3 mm Allen key, wind back the tensioner (turn
clockwise) until the snail engages in the park position.
1 Remove the tensioner housing securing bolt (4 Fig. 2) and
withdraw the tensioner assembly.
1 Re-position thetiming chain between the upper dampers.
1 Remove the cylinder head front securing bolts.
1 Remove the remaining cylinder head securing bolts/ nuts.
Remove the upper static damper pedestal assembly and
remove the cylinder head.
0 1 Fit an elastic band to retain the dampers and chain.
. Remove and discard the head gasket.
1 Remove and discard the exhaust manifold sealing rings.
1 Place the cylinder head on suitable blocks on a bench.
Clean the cylinder head thoroughly and check the cylinder
head and cylinder block for warping, bowing or cracks.
Renew if defective.
1 Fit a new cylinder head gasket.
1 Fit the cylinder head assembly to the engine, ensure no
hoses or cables are trapped.
A2616
Fig. 1
Fin. 2
Issue 1 August 1994 13
AJ16 Engine Service Manual
= Refit the upper static damper assembly.
lighten the cylinder head bolts with reference to the se- quence shown in Fig. 1.
CAUTION: The cylinder head bolts MUST be renewed dur- ing assembly and torque tightened as de-
scribed in Section 2.1, SPS Joint Control
System.
Ensure that the camshaft is still on TDC using Ser
-
vice Tool 18G 1433 (1 Fig. 2).
Fit the harness clip and hose bracket to the cylinder head
front securing bolts.
Fit and tighten the front securing bolts.
1433 (1 Fig. 2).
b:
= Check the camshafts are set atTDC using Service Tool 18G
= Raise the timing chain from between the upper dampers.
Remove the elastic band.
= Fit and engage the sprockets to the chain and camshafts.
. Move all the chain free play to the tensioner side.
Fit upper chain tensioner tool 18G 1436/A (2 Fig. 3).
Fit and tighten the tool securing bolts (1 Fig. 3).
Tension the timing chain.
sprocket
(1 1 Fig. 4) and align the securing bolt holes.
bolts
(2 Fig. 4). Lock over the tabs.
Release the tension on the timing chain.
Re
-position the
chain over the camshafts.
. Remove the camshaft coupling (12 Fig. 4) from the
. Fit the tab washers (1 Fig. 4). Fit and tighten the securing
. Slacken off the upper chain tensioner tool securing bolts.
Remove the upper chain tensioner tool 18G 14361A (2 Fig.
Clean the tensioner assembly and gasket faces.
3).
Fit a new housing gasket (10 Fig. 4). Lubricate andfita new '0' ring (9 Fig. 4).
. Fit the tensioner to the cylinder head.
. Fit and tighten the tensioner assembly securing bolt
Clean the valve assembly and fit new '0' rings.
Using an Allen key, release the tensioner, ie turn the Allen
(4 Fig. 3).
Lubricate the tensioner valve.
key
anti-clockwise.
I
104 2 5 7 I l2
I Fig. 1
1
Fig. 2
Fig. 3
Fig. 4
Issue 1 August 1994 14
AJ16 Engine Service Manual
4.5 Cylinder Head, Overhaul
SRO 12.29.19
1 Remove the cylinder head, see Section 4.4.
1 Place the cylinder head on suitable blocks on a bench.
1 Remove the spark plugs and the intake and exhaust mani-
folds.
1 Mark the position of the camshaft caps relative to the
head, remove the cap securing bolts and remove the caps
(1 Fig. 1).
1 Remove the camshafts.
. Using a magnet, lift out the cam followers (1 Fig. 2).
1 Remove the valve springs, using Service Tool MS 1519A,
1 Retrieve the collars, collets and spring retaining plates.
1 Remove the valves, noting the relationship between valve
and guide to ensure correct pairing during re-assembly.
* Remove the seals from the intake valve guides and re- move the cylinder head rear blanking plate.
1 Clean all component parts.
1 Check for wear and burning of valves or seats.
1 Check the cylinder head face for distortion.
1 If distortion is evident, a maximum of 0,25 mm may be re- moved by skimming the cylinder head.
1 Taking care not to damage the inside surface of the com-
bustion chambers, clean the intake and exhaust ports.
CAUTION: When using scrapers or wire brushes for re- moving carbon deposits, avoid scratching the
valve faces and seats. A soft wire brush is the most suitable implement for this purpose.
1 Clean all carbon and other deposits from the valve guide
using a suitable valve guide brush. Thoroughly wash the
cylinder head to ensure that all loose carbon is removed
and dry the cylinder head with a high pressure air line.
. After cleaning and polishing each valve, examine the
stems for straightness and wear, using a suitable dial
gauge and vee
-block see example at Fig. 3.
1 Examine the valve faces for burns, pitting and distortion.
Renew any valves that are excessively worn, bent, or too
badly pitted to be salvaged by refacing.
Support the
valves using a wooden block.
valve spring compressor.
/ 112 310
Fig. 1
Fia. 2
I
JlZ 268
Fia. 3 I " 1
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AJ16 Engine Service Manual
. The dimension must be taken between the valve stem and
the back of the cam. Should
this dimension not be ob-
tained, metal must be ground from thevalveseat of the in-
sert.
&&: Use only suitable grinding equipment.
* Remove only very small amounts of metal from the valve
seat at one time before re-checking the clearance.
. Examinethecamfollowersforwear on the topface. Check
for any sign of barreling on the side faces (Fig. 1). Renew
all followers that are worn or suspect. Wash the valves,
springs, collets, followers and air dry.
. After the valve springs have been thoroughly washed,
they must be examined for fatigue and distortion. Renew
as necessary.
. Test the valve springs either by comparison with the fig- ures given in Service Data in the Preliminary Pages, or by
comparison with a new valve spring (using a recom- mended valve spring testing machine).
. To test against a new valve spring, insert both valve
springs end to end between the test equipment. Apply a
load to partly compress the springs and measure their
comparative lengths (Fig.
2).
&@:
. If the distance 'A' is smaller than the distance 'B', then 'A'
b: Spring distortion is determined by positioning the
spring upright on a surface plate and checking the
squareness of each end with a set square (Fig.
3). All
valve springs which have diminished in length and/ or are not square must be renewed.
. Fit the valves into the guides and place the cylinder head
on wooden blocks.
. Fit the valve spring seats, intake valve guide oil seals,
springs and collars.
. Compress the springs using Service Tool MS 1519A and
insert the split collets.
. Refit the original shims (1 Fig. 4) in the valve collar re- cesses. (Ensure that the shims are seated correctly and fit
the cam followers, see Section 4.3).
If the cylinder head has been overhauled to the ex-
tent of having the valve seats recut, each shim
should be 0,010 in. smaller than the original.
. Lubricatethecamshaftsand fittothecylinder head,ensur- ingthattheyarefittedwiththeslotsto thetop. Fitthecam- shaft caps and torque tighten the securing bolts. Measure
the valve clearance between the heel of the cam and the
cam follower, turning the camshaft as necessary to
measure
all the clearances see Section 4.3.
It is advisable to set the valve clearances to the
upper
limit to allow for the clamping effect exper- ienced through torque tightening upon engine re- assembly.
Afinal checkof the valve clearances should be done
when the cylinder head is fitted and torque tigh
- tened to the cylinder block.
Clean the cylinder head thoroughly and checkthe cylinder
head and cylinder block for warping, bowing or cracks.
. Fit the cylinder head, see Section 4.4.
'A' is the old spring.
must be renewed.
&&:
m:
&@:
Fig. 1
K
Fig. 2
I Fig. 4
Issue 1 August 1994 18
0 4.6 Cylinder Head Casting, Renew
SRO 12.29.15
1 Remove the cylinder head, see Section 4.4.
1 Place the cylinder head on suitable blocks on a bench.
1 Remove the spark plugs.
1 Remove the intake valve camshaft cap securing bolts.
1 Remove the camshaft caps.
1 Remove the camshaft.
1 Repeat the procedure for the exhaust camshaft.
1 Remove the cam followers and shims, noting the posi-
1 Remove the valves using Service Tool MS 1519A valve
1 Remove the seals from the intake valve guides.
1 Remove the rear blanking plate.
1 Clean all components and examine for wear and damage.
Renew any worn or damaged parts as necessary.
1 Clean thoroughly the new cylinder head casting.
1 Refit the rear blanking plate to the new cylinder head.
0 1 Smearfinegrindingcompound on tothe face ofonevalve.
1 Oil the valve stem.
1 Fit the valve to the head.
1 Lightly lap the valves into the seats, leaving a smooth fin-
ish to both surfaces.
Note: Excessive lapping will groove the valve face, result- ing in poor seating when hot.
1 Clean the valve and seat.
1 Repeat the procedure for the remaining valves.
1 Fit a new seal to the intake valve guide.
1 Lubricate the valve stem. Fit the valve to the guide. Fit the
. Fit Service Tool MS 1519A spring compressor to the valve.
1 Compress the valve spring, fit and seat the collets, and re- lease the clamp.
1 Repeat the procedure for the remaining valves.
. Refit the shims.
1 Ensure that the shims are seated correctly.
1 Lubricate and fit the cam followers (Fig. 1).
. Lubricate the camshafts and bearings.
1 Fit the camshafts.
1 Fit the camshaft caps.
1 Fit and torque tighten the camshaft cap securing bolts.
. Measure the valve clearance between the heel of the cam
and the cam follower (Fig.
21, turning the camshaft as
necessary to measure all the clearances, see Section 4.3.
Afinal check of the valveclearancesshould be done
when the cylinder head is fitted and torque tigh- tened to the cylinder block.
1 Clean the cylinder head thoroughly and check the cylinder
head and cylinder block for warping, bowing or cracks.
Renew if necessary.
tions
for re
-assembly.
spring compressor.
spring seat, spring and collar.
Note:
1 Fit a new cylinder head gasket.
1 Fit the cylinder head assembly, see Section 4.4.
I II
Fig. 1
JI1 U4
Fig. 2
Issue 1 August 1994 19
AJ16 Engine Service Manual
4.7 Piston
and Connecting Rod, Engine Set, Renew
SRO 12.17.10
. Remove the engine and transmission unit from the ve- hicle, see Section 3.1 in the appropriate Vehicle Service
Manual.
1 Remove the transmission unit from the engine and fit the
engine to a stand.
. Remove the cylinder head, see Section 4.4.
* Remove the oil pan, see Section 4.27.
1 Remove the oil pump, see Section 4.31.
. Remove the windage trays securing bolts. Remove the
windage trays (6 Fig. 1).
* Remove the connecting rod nuts (1 Fig. 2) in connecting
rod pairs(1 &6,2 &5,3&4cylinders)andremovethecon- necting rod bearing caps (2 Fig. 2). Note the position of
the cap to connecting rod. Discard
the connecting rod
bearing nuts.
Push the pistons up and through the top of the cylinder
block.
. Remove the piston pin snap-rings (1 Fig. 3)from each pis- ton, remove the piston pin (2 Fig. 3) and separate the pis-
ton (3 Fig. 3) from the connecting rod (4 Fig. 3).
. Check the connecting rods for out of balance, twist and
bend. If any connecting rod is bent, twisted or out of bal- ance with the other five, then the complete set must be re- newed. Renew
the connecting rod bearing bolts.
.a
Fia. 1
,11613
Fig. 2
I 4 Ii I
Fig. 3
-3
ill 631
Issue 1 August 1994 20