1. Camshaft on intake side — 2. Hydraulic tightener —
3. Camshaft on exhaust side — 4. MORSE chain —
5. Rocker arms — 6. Hydraulic reacting tappet —
7. Valve assembly.
Description
The timing system is the type with a twin camshaft in the head
and four valves per cylinder with hydraulic tappets.
Motion is transmitted by the crankshaft, via a toothed belt,
to the gear keyed onto the intake valve drive shaft. The drive
transmission of the exhaust valve drive shaft takes place via
a MORSE-type chain kept under tension by a hydraulic
tightener.
The toothed belt, moreover, drives the water pump and the
high-pressure pump CP3 and is kept at the right tension by
an automatic tightener roller.
The four valves move by the action of the “free” rocker arms
(with no supporting shaft).
The rocker arms, one per valve, are always in contact with
the corresponding cam and are kept in this position by a
hydraulic reacting tappet, thereby eliminating the need for
periodical adjustment.
75469
75471
75470
75472
75473
Figure 180
Figure 181
Figure 182
Figure 183
Figure 184
Take out the screws (1) and remove the rear cover (2)
together with its gasket.
Insert a suitable pin (2) in the hole (
⇒) of the chain drive (3).
Take out the screws (4) and (6) with their washers (5) for
fixing gears to the camshafts.
Take out the screws (7) and remove the chain drive (3) from
the overhead (1).
Turn over the overhead (1) and, taking care not to damage
the seats, extract the camshafts (2) and (3) from it.
TIMING SYSTEM DIAGRAM
5412
TIMING SYSTEM
F1A ENGINE
99
D
AILY
E
URO