Jaguar AJV8 engine / 5HP24 transmission. Manual - part 2

Engine

AJ-V8/5HP24

9

Connecting Rods and Pistons

The connecting rods are manufactured in sinter
forged steel. The bearing caps are produced by
fracturing the opposing sides of the connecting rod at
the bearing horizontal center-line. As well as being
easier to manufacture, when re-assembled the
fractured surfaces interlock to form a strong
seamless joint. The cylinder position is etched on
adjoining sides of the joint to identify matching
connecting rods and bearing caps. The connecting
rod bearings are lead/bronze split plain bearings.
The pistons are of the open ended skirt design with
flat upper surfaces to reduce heat absorbtion. Three
piston rings, two compression and one oil control, are
installed on each piston. Each piston is installed on a
wrist pin located in a lead/bronze bushing in the
connecting rod.

Sump

The sump consists of an aluminum alloy structural
sump bolted to the bedplate, and a pressed steel oil
pan bolted to the structural sump. A windage tray
attached to the top of the structural sump isolates
the oil pan from the disturbed air produced by the
rotation of the crankshaft, to prevent oil aeration and
improve oil drainage. A rubber plug at the rear of the
structural sump seals the port that provides access to
the torque converter securing bolts. The engine oil
drain plug is located at the front right corner of the oil
pan.
A silicon rubber in-groove gasket seals the joint
between the oil pan and the structural sump; a bead
of sealant seals the joint between the structural
sump and the bedplate.

CONNECTING ROD AND PISTON

303-014

SEALANT TRACK ON STRUCTURAL SUMP

303-021

Engine

AJ-V8/5HP24

10

Starter and Drive Plate

The engine starter motor is installed at the rear
right side of the engine, at the cylinder block to
bedplate split line (for further details of the
starter motor see Technical Guide, XK8
Introduction).
The starter drive plate is attached to the rear of
the crankshaft. A timing disc, for the engine
speed sensor, is spot welded to the front face of
the drive plate.

STRUCTURAL SUMP AND OIL PAN

STARTER MOTOR

303-062

Torque
Converter
Access

303-010

Engine

AJ-V8/5HP24

11

Cylinder Heads

The cylinder heads are unique to each cylinder
bank. Deep seated bolts, to reduce distortion,
secure the cylinder heads to the cylinder block.
Two hollow dowels align each cylinder head with
the cylinder block.
The cylinder head gaskets consist of a silicon
beaded composite gasket with metal eyelets for
the cylinder bores, similar to that on the AJ16
engine.
Each cylinder head incorporates dual overhead
camshafts operating four valves per cylinder via
solid aluminum alloy valve lifters. Steel shims in
the top of the valve lifters enable adjustment of
valve clearances.
The lightweight valve gear provides good
economy and noise levels. Valve head diameters
are 31mm (1.220 in) for the exhaust and 35mm
(1.378 in) for the intake. All valves have 5mm
(0.197 in) diameter stems supported in sintered
metal seats and guide inserts. Collets, valve
collars and spring seats locate single valve
springs on both intake and exhaust valves. Valve
stem seals are integrated into the spring seats.
The camshafts are manufactured in chilled cast
iron. Five aluminum alloy caps retain each
camshaft. Location numbers, 0 to 4 for the intake
camshaft and 5 to 9 for the exhaust camshaft,
are marked on the outer faces of the caps. The
rear of B bank intake camshaft has a timing ring
for the camshaft position sensor. A flat,
machined near the front of each camshaft,
enables the camshafts to be locked during the
valve timing procedure.

CAMSHAFT POSITION SENSOR
TIMING RING

303-054

The 14 mm spark plugs, one per cylinder, locate
in recesses down the center-line of each cylinder
head.
An engine lifting eye is cast into the front of each
cylinder head (the rear lifting eyes, one on each
cylinder head, are bolt-on tools).

TIMING DISC

STARTER DRIVE PLATE

303-035

303-034

Engine

AJ-V8/5HP24

12

Timing Gear

Single row primary and secondary chains drive
the camshafts of each cylinder bank. The primary
chains transmit the drive from two sprockets on
the crankshaft to variable valve timing units on
the intake camshafts. The secondary chains
transmit the drive from the variable valve timing
units to sprockets on the exhaust camshafts.

A BANK CYLINDER HEAD

303-047

Lifting
Eye

Intake Camshaft

Exhaust Camshaft

(Continued on Page 14)