Pfaff 433 - Changing the Oil

The operator will not encounter any difficulties in regulating the oil flow
correctly when she remembers that more oil is required for stitching
heavily
dressed materials or for long runs at high speed (bed sheets or
bath towels) and that the normal oil flow, or even a little less, will suffice
for sewing flimsy ond delicate materials which, without an exception, ore
all undressed.
For short runs and speeds below 4,000 s.p.m. in the garment manufacture,
fhe oil flow to the hook may be shut off completely in favor of manual
oiling.
If the hook should either blacken the thread, or become so hot that you
cannot touch it with your hand, this is a sure indication of inadequate oiling.
On the
other hand, if oil spots appear on the bobbin case this indicates
that there is an excessive flow of oil passing to the sewing hook and that
soiling of the material may result.
These signs greatly help in keeping the oil flow to the hook at the correct
level ond in adapting it to specific operating requirements.
24. Changing the Oil
As with any other high speed sewing machine with automatic lubrication,
regular changing of the oil will do much to increase the service life
of the
machine. Particularly during the break-in period, the oil should be changed
more frequently.
This is necessary in order to remove the grit which occurs
particularly while a new machine is being broken in. As the overheating
Of the oil does not affect its lubricity, it is not necessary to change the pil
in order to correct this condition.
To comply with the above requirement, follow the schedule given below.-
First change
after one week's operation
Second change after four week's operation
Third change after three months' operation
and thereafter every three months
Of course, this schedule applies only to the automatic lubrication system.
The oil which is used up in the separate hook lubrication system has to be
replenished at shorter intervals.
To drain the oil from the bed oil reservoir, take out the large drain screw
while the machine is idle. Take care that no used oil, mud or grit remains
in the reservoir.
The drained oil may be reused for other lubricating purposes after it has
been filtered through several lays of linen.
New oil is filled in as instructed in Section 2.
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From the library of: Superior Sewing Machine & Supply LLC