Hydrostatic Transmission Service, LLC offers lip type shaft seal on Series 40 pumps and motors The seals on these pumps and motors can be replaced with no major disassembly to the unit, although, replacement of the shaft seal calls for removal of the pump or motor from the machine. Then take out the retaining ring from the housing.
With great ease take out the seal from the housing bore. A slide hammer type puller should be used to aid in prying the seal out, otherwise the seal may become punctured if using a sharp instrument. Restraint should be taken so the housing bore or shaft doesn’t become damaged. The seal is not reusable after it’s removal.
Before installing the new seal, look the sealing areas over on the shaft for rust, wear, or contamination. Also if it calls for it polish the sealing area.
The key end of shaft needs to be wrapped with lightweight plastic to avoid damage to the seal lip during installation. Grease the inside thickness of the new seal with petroleum jelly.
Slide the new seal over the shaft and press it into the housing bore. Be careful not to damage seal. A seal installer tool can be made to aid in installing the seal.
Sundstrand Hydrostatic Pump - Sundstrand Hydraulic Pump
Bypass Valve (Pump)
Unbolt the bypass valve from the housing. Look over the valve and mating seat for damage or foreign material and while this is open Hydrostatic Transmission Service,LLC recommended the O-ring and back up ring be replaced.
NOTE: Bypass valves are available with basic bypass orifices for specific applications. Hydrostatic Transmission Service,LLC recommends referring to the suitable Service Parts Manual for more information.
Then put back the bypass valve into the housing. Torque to 7to10tt.lbs. (9.5 to 13.6 Mm).
Drive shafts - a wide assortment of options are offered to suit every requirement.
High power swash plates on variable pumps and motors - oppose deflection under high load.
High potency cast iron housings -
supply greater noise damping and wall force.
High flow check valves in pumps –maintain the system at it’s highest performance with very little drop in pressure.
Charge pumps on pumps - gerotor type, numerous displacement options are accessible to curtail the needs of every purpose. Pumps are made of cast iron.
Cartridge shaft seal-allows itself to easy serviceability. Motorized face seal design makes the pumps more efficient for high speed and case pressure
Advanced cylinder barrel design –helps with high pressure and speed.
Fixed clearance slipper hold down -
Models 33 through 64 allow functions at high speed and decrease resistance. Model 76 is a ball guide unit.
Pistons - have more contact with cylinder bore ensuring low leakage.
Hydraulic servo control – offers effortless operation, along with very low control pressure.The hefty servo pistons grasp the swash plate position and offer damping.
Large case drain ports - lessen case back pressure.
Model (unit Number) 33 39 46 54 64 76 Displacement in'/rev 3.32 3.89 4.60 5.44 6.44 7.62 cm'/rev 54,4 63,7 75,3 89,1 105,5 124,8 Highest Shaft Speed RPM @ 18° 4510* 4160 4160 3720 3720 2775 RPM @ 10° 5380- 5380- 5380" 4810- 481(T 3425- Highest Amoutn of Torque t Ib-in 2959 3511 4149 4916 5807 6911 Nm 334 397 469 556 656 781
The highest swash plate angle on model 33 motors is 15.5°. These shaft speeds need the highest amount of charge pressure release: 340 psi [23 bar] pump and 280 psi [19 bar] motor.