PRODUCT INFORMATION
INDEX
DATE
Dep. 2
IT-G-E-30-001e
B
September 2015
VENTURI TYPE CARBURATION - DESCRIPTION
2/5
Figure 2 Zero pressure regulator
The ZPR shall be mounted as near the adjustment screw or the gas control valve as possible, respecting the
minimum distance specified by the regulator manufacturer, and in such a way as to avoid the engine vibrations
Kohler
uses two models of pressure regulators:
-
FRN: This regulator must always be placed with the outlet pressure adjusting spring facing downwards. It
needs an inlet air pressure compensation line downstream of the filters.
-
FRNG: This type of regulators can be installed with the outlet pressure adjusting spring facing up or facing
downwards. They require no inlet air pressure compensation line downstream of the filters; fitting a
compensation line could lead to problems with the engine operation. Since there is no compensation line, they
require more frequent monitoring of the exhaust emissions to avoid air-fuel ratio misadjustments due to
clogged air filters.
For this type of regulators (supplied by
Kohler
), the inlet gas pressure must not exceed 50 mbar.
3.
GAS FLOW CONTROL
3.1 MAIN ADJUSTMENT SCREW (MAS)
The main adjustment screw for the mixture ratio lies between regulator and carburettor. It checks the flow of
fuel to the carburettor.
For the MAS setting procedure, see IT-G-A-30-001e
Gas outlet
Gas inlet
Outlet pressure adjustment
2.4.6
O&M_2.002211.810_A_10_2016
