Pressure relief valve, location/task/design/function

GF47.31-P-3100A

11.5.98

ENGINE 112, 113 in MODEL 129 with CODE (494a) USA version

ENGINE 111, 112 in MODEL 170 up to 31.8.00 with CODE (494a) USA version

ENGINE 112, 113 in MODEL 210.2 with CODE (494a) USA version

ENGINE 112, 113 in MODEL 210.0 up to 31.5.01 with CODE (494a) USA version

ENGINE 112, 113, 137 in MODEL 220 up to 31.8.00 with CODE (494a) USA version

ENGINE 137, 113 in MODEL 215 up to 31.8.00 with CODE (494a) USA version

P47.31-2001-10

Pressure relief valve design

82 Pressure relief valve

a ORVR vent line (from filler neck to activated charcoal canister)

b Hose line to pressure relief valve

c Fuel overflow line to atmosphere

d Air admission to diaphragm chamber

Pressure relief valve location	Model 129	GF47.31-P-3100-01A
	Model 170	GF47.31-P-3100-01G
	Model 210	GF47.31-P-3100-01F
	Model 215, 220	GF47.31-P-3100-01M
Pressure relief valve task	Limiting the pressure in the ORVR vent line if fuel tank overfilled or if gasoline pump nozzle faulty (does not switch off).
Pressure relief valve design	Housing with internal diaphragm which seals off the line to the pressure relief valve by means of a spring.
Pressure relief valve function	The diaphragm lifts off at a pressure of approx. 60 to 90 mbar. The fuel overflow line to atmosphere opens. Air is admitted to the diaphragm chamber.