9
Parker Hannifin
Pump and Motor Division
Trollhättan, Sweden
Service Manual
Series F11
Bulletin HY30-5503-M1/UK
If play indicated in the figure is exceeded then re-
place all piston and ring assemblies in the unit. Never
replace individual worn piston and ring assemblies.
5. Check that the shaft surface in contact with the
shaft seal is in good condition; if grooved, corroded,
or otherwise damaged, the shaft should be replaced.
Note
When lapping the valve plate, up to .002 in. can be
removed. If .002 in. is not sufficient to obtain a flat
surface free of scratches, the part should be repla-
ced.
4. If the bearing cups are loose, the shaft lock nut
should be tightened. Correct bearing pre-load has
been obtained when the spacer ring can be moved
sideways without being loose. Note, for the bigger
units quite a substantial force is required.
Reconditioning and Replacement of
Parts
After disassembly, all parts should be thoroughly clea-
ned in a suitable solvent.
Caution: Follow directions for use of solvent carefully.
Protect your hands and eyes from the solvent.Solvent
may also be inflammable.
If leakage of the F11 unit was too high, the following
parts are generally worn or damaged:
Series F11-5 through -150:
- Valve plate
- Cylinder barrel port surface (facing valve plate)
- Piston rings or piston assy
Series F11-250:
- Bearing plate
- End cap port surface (facing bearing plate)
- Piston rings or piston assy
Max 50%
Old version
Not available
Scratches and wear marks on these parts always affect the
performance of the unit; they should be replaced if scrat-
ched or worn.
1. Shaft seal and o-rings should always be replaced.
2. Replace spherical piston rings that are worn more
than 50 % of the spherical surface as shown. A small
retaining ring pliers will facilitate the removal. When
installing a new piston ring, make sure the spherical
surface coincides with the shape of the piston head.
3. On series F11-5 through -150, the valve plate
surface can be reconditioned by careful lapping.
Series F11-250 end cap port surface can be lapped
but the bearing plate must be replaced if worn.
Production of the spherical piston ring is discontinued.
The old ring and piston has to be replaced by the
laminated version.
Max .0.2 mm
