Figure 4-23(2). Heavy duty bearing assembly, application parts, exploded view.
uneven weight distribution plus faulty lubrication. Wear
4-10. Journal Care
marks will indicate whether the journal will become
Overheating (hotboxes) causes the oil in the journal box
tapered or not.
to carbonize or burn. After the oil in the packing has
b. Renewal Precautions. In the process of changing
burned, the remaining black residue sticks to the journal
wheels and/or applying new journal bearings to car
bearing and scratches or cuts the journal, which is
wheels, the following precautions will be observed.
relatively soft when hot. A "rough" journal can be
detected by feel, either by using the tips of the fingers,
(1) The surface of the journal should be smooth and
or preferably by using the pointed end of a waste grab
thoroughly clean before the bearing is applied. Abrasive
paper or cloth should not be used on or about axle
becomes scarred, it is unsafe for further service and that
journals under cars. Journal surfaces should not be
pair of wheels will be replaced.
wiped with waste.
4-11. Journal Bearings
(2) Plain journal bearings should be clean and
smooth before application. Do not use abrasive paper
a. General. Like the journal, the main cause of
or cloth for removing irregularities If necessary use a
journal bearing failure can be traced to the lack of
half-round file or scraper.
lubrication Bearing damage will occur when there is not
enough oil on the journal to overcome the effects of
(3) Apply a thin coat or car oil to the lining before
friction developed between the journal and bearing,
applying a bearing. Never wipe the lining or journal with
whether babbitt lined brass or steel roller bearing If one
end of the bearing is excessively worn, the journal
should be examined for tapering. Tapering is caused by