Introduction
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Installation and maintenance
Requirements for the installation site
ProVent² 500 can be mounted on the engine or frame of the machine / vehicle.
Inlet connection to the engine
The blow-by gases reach the ProVent² 500 via the inlet nozzle. Possible extraction points for the blow-by gas
must be in an area with a low oil content. These are areas in which there are no moving parts and no splash oil
is present, e.g. upper areas of the crankcase or the cylinder head cover.
This crankcase outlet must be connected to the ProVent² 500 system inlet port.
Connection principles Oil return
Connection below oil level
The oil return is connected to the engine via a drainage pipe below the minimum permissible oil level of the oil
pan. When the engine is switched off (no blow-by gas), the same oil level is present in the oil pan and the
drainage pipe.
When the engine is running, this oil trap acts like a siphon so that the blow-by is led over the oil separator when
the oil is sucked out of the outlet nozzle. The differential pressure of the oil separator determines the height of
the oil column in the oil return line. If an oil separator element is installed in the system, the same negative
pressure is present in the oil return line during operation as at the oil separator. These relationships must be
taken into account when selecting the installation location.
Connection above oil level
This connection variant requires an optionally available non-return valve. The valve is installed in the drainage
pipe as close as possible to the oil level (approx. 30 to 50 mm above maximum oil level).
During operation, the separated oil accumulates above the non-return valve. During operation, the check valve
is closed by the differential pressure of the separator. If the weight of the oil column exceeds the closing
pressure of the valve, or after switching off the engine, the separated engine oil flows back into the oil pan.
Any inclined positions that may occur in mobile applications that lead to a fluctuating oil level must always be
taken into account. MANN+HUMMEL generally recommends the use of a check valve for all ProVent
installations.
Outlet within closed systems
The outlet nozzle is connected to the engine intake (after the air filter, but before the turbocharger, if fitted). The
highest possible point above the oil level or non-return valve must be selected as the installation location, but at
least 350 mm for the standard separator element.
The suction vacuum present during operation of a closed system sucks the blow-by via the respective ProVent²
500 and returns the cleaned blow-by gas to the intake tract of the engine. When selecting the installation
location, the type of oil return must be taken into account.
Outlet within open systems
The outlet nozzle remains open. The cleaned blow-by gas is discharged into the open air.