PGO BR-500, Руководство по обслуживанию

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- To obtain a proper lubrication
of the brasses, it is necessary
to have an optimum lubrication
pressure (4 bar) and a good oil
rate; to this purpose, the
brasses must be placed
properly, so as to not have
shuttering in the oil feeding
channels.
- Bench brasses are realised
with 2 half-bearings, one of
which is solid while the other
has holes and seats for
lubrication.
- The solid half-bearing is intended to stand the thrusts caused by combustion, and for this
reason it is arranged opposed the cylinder.
- To prevent shutters in the oil feeding channels, the matching surface of the two half-
bearings must be perfectly orthogonal to the cylinder axis, as shown in the figure.
- The oil feeding channel section is also affected by the brass driving depth relative to the
driving shaft axial clearance containment plane.
N.B.:
To keep such position of the brasses on the crankcase, driving is forced on cast-iron
rings inserted in the casting of both half-crankcases.
- Check the brass diameter in
the 3 directions shown in the
figure.
- Repeat the measurements
for the other half of the brass.
See figure.
N.B.
: Do not take the measure
on the half-bearing matching
surface since the ends are
released to allow deformation
upon insertion.
- The standard brass diameter after driving is variable on the basis of a coupling selection.
- The brass seats into the crankcases are classified into 2 categories as for the driving shaft
Cat. 1 and Cat. 2.
- Brasses are divided into 3 categories according to their thickness. See the table below:
TYPE IDENTIFICATION THICKNESS
A
Red 1,982 ~ 1,987
B
Blue 1,987 ~ 1,992
C
Yellow 1,992 ~ 1,997
PGO BR-500 ENGINE
N.B.: For overhauling with spare parts, match the shaft withtwo shoulders of category 1 to crankcase
FC1 (or category 2 to crankcase FC2).
A spare crankcase cannot be combined with adriving shaft with mixed categories. Spare shafts have half-shafts of the
samecategory.
N.B.:
To replace the half-shafts, remove the counter-shaftbearings as described above. Remove the complete
driven pulley and theanti-flapping roller from the transmission side half-crankcase, as described inChapter 3 ?
Legal Notes
Half-shaft
category
Half-shaft
category
Brass
category
1 B FC1
Dwg. CM1033015001
2 C
1 A FC2
Dwg. CM1033015002
2 B
P.10-113
Crankcase & Driving shaft