DCE80-100E
Technical Handbook
Hydraulpump
Service
31
P.Group 70
TDCE01
04GB
Permissible wear of the pump components
9. Pump body
The pump pressure presses the pump gears towards the walls of
the body on the low-pressure side, and since the shafts and bear-
ings wear, the pump gears will rub against the body.
If the pump body has worn more than 0.13 mm, it must be
changed. Check by placing a straight edge inside the pump body,
and use feeler gauges to measure the wear.
10. Driven gear
The driven gear must be replaced if any kind of scoring or wear
is found on the shaft ends or teeth.
11. Driving gear
Fit a new driving gear if wear can be felt on the sealing surfaces.
12. Pressure plates
The pressure plates seal at the sides of the pump section. Wear
of the pressure plates will cause internal leakage. The maximum
permissible wear is 0.05 mm. Fit new pressure plates if the exist-
ing ones are scored, worn or pitted.
Check the centres of the pressure plates where the teeth mesh.
Wear here indicates that there are impurities in the fluid. Pitting
indicates cavitation or the formation of gas. Discolouration of the
pressure plates indicates overheating.
13. Dowels
If a dowel or its hole has been damaged, the dowel and possibly
the section containing the dowel must be changed.
If more than reasonable force is needed for pressing in a dowel,
this may be due to inadequately deburred or fouled parts, defor-
mation of the dowel or poor fit of the dowel hole.
14. Plain bearings and roller bearings
If new gears are fitted, the bearings must also be changed. Plain
bearings must be a hard press fit. Roller bearings must be a light
press fit, and it is acceptable if they can be pressed in by hand. If
a bearing can drop out of its seat, the hole is too large.
15. Seals
Replace all rubber and plastic seals, including all O-rings, seals
at the pressure plates, shaft seals and gaskets.
To Next Page
Loading...
