Repair Manual

IGNITION AND INJECTION
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CATALYTIC CONVERTER
The catalytic converter (drawing 1, position 17) is placed on the burned gases evacuation
track between the primary down tube and the detector it is three ways type and it is used for
simultaneous transformation of the three gases existing in the evacuation gas, according to the
following chemical reactions:
C m Hn + ( m+n/4 ) O
2 m CO2 + n/2 H2 O
2 CO + O
2 2CO2
2 NO + 2 CO N2 + 2CO2
The catalytic converter is honeycomb shaped, in ceramic, covered with a very thin film of
active catalytic substances (Platinum, Rhodium and Palladium). It accelerates the
oxidation and chemical reaction of the noxious substances existing in the evacuated burned gases.
This ceramic structure is protected by a stainless steel case, resisting to high
temperatures and environmental agent action.
WARNING !
Knowing that the catalytic converter reaches high temperatures during the func-
tioning it is forbidden to install it in areas storing inflammable materials – fire hazard.
In order not to damage the catalyst during a difficult engine starting, do not insist
in repetitiously trying to start the engine; pushing the vehicle it is also forbidden, one
can use a helping battery.
The engine shouldn’t run without sparking at one of its cylinders, even during test-
ing; a not burned fuel can reach and damage the catalyst.
The maximal permitted values of the noxious substances (vehicle technical checking):
- CO < 0,4 % vol.
- HC < 100 ppm
- CO
2 > 12 % vol.
- 0,97 < λ < 1,03
The above mentioned formula determination is done at an idle rotation of 800 ± 50 rot/min
after a minimum period of 5 minutes since the engine start up (engine T = 85 – 90 °C).
DESCRIPTION OF THE SYSTEM
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