Flushing Instructions - WÄRTSILÄ WÄRTSILÄ 50DF Product Manual

7. Lubricating Oil System
7.5

Flushing instructions

Flushing instructions in this Product Guide are for guidance only. For contracted projects,
read the specific instructions included in the installation planning instructions (IPI).
7.5.1 Piping and equipment built on the engine
Flushing of the piping and equipment built on the engine is not required and flushing oil shall
not be pumped through the engine oil system (which is flushed and clean from the factory).
It is however acceptable to circulate the flushing oil via the engine sump if this is advantageous.
Cleanliness of the oil sump shall be verified after completed flushing.
7.5.2 External oil system
Refer to the system diagram(s) in section External lubricating oil system for location/description
of the components mentioned below.
The external oil tanks, new oil tank and the system oil tank (2T01) shall be verified to be clean
before bunkering oil.
Operate the separator unit (2N01) continuously during the flushing (not less than 24 hours).
Leave the separator running also after the flushing procedure, this to ensure that any remaining
contaminants are removed.
If an electric motor driven stand-by pump is installed this pump shall primarily be used for the
flushing but also the pre-lubricating pump (2P02) shall be operated for some hours to flush
the pipe branch.
Run the pumps circulating engine oil through a temporary external oil filter (recommended
mesh 34 microns) into the engine oil sump through a hose and a crankcase door. The pumps
shall be protected by the suction strainers (2F04, 2F06).
The automatic filter (2F02) should be by-passed to prevent damage. It is also recommended
to by-pass the lubricating oil cooler (2E01).
7.5.3 Type of flushing oil
Viscosity
In order for the flushing oil to be able to remove dirt and transport it with the flow, ideal viscosity
is 10...50 cSt. The correct viscosity can be achieved by heating engine oil to about 65°C or
by using a separate flushing oil which has an ideal viscosity in ambient temperature.
Flushing with engine oil
The ideal is to use engine oil for flushing. This requires however that the separator unit is in
operation to heat the oil. Engine oil used for flushing can be reused as engine oil provided that
no debris or other contamination is present in the oil at the end of flushing.
Flushing with low viscosity flushing oil
If no separator heating is available during the flushing procedure it is possible to use a low
viscosity flushing oil instead of engine oil. In such a case the low viscosity flushing oil must
be disposed of after completed flushing. Great care must be taken to drain all flushing oil from
pockets and bottom of tanks so that flushing oil remaining in the system will not compromise
the viscosity of the actual engine oil.
7-16 Wärtsilä 50DF Product Guide - a16 - 9 September 2016
Wärtsilä 50DF Product Guide