Concentric Hydraulic Pump, 28 GPM, 2-Stage, Model# 1080036

This is a clockwise pump designed to be directly coupled to the engine's PTO shaft (use a jaw-type flexible coupling).

All Haldex two-stage pumps are a 4:1 ratio. That is, the theoretical GPM when the unloader activates (around 700 PSI) will be one fourth the free-flow rating. Therefore, the approximate GPM when in high pressure mode will be 7.

To power the pump from a tractors PTO, you would need a speed-increasing gearbox. 549 RPM would be too low for the pump. It is designed to operate at around 1750 RPM.

The maximum RPM for this hydraulic pump is 3600 RPM.

This hi-low pump will produce two different flow rates, depending on the system pressure. For pressures above 650 PSI, this should produce about 2.5 GPM at 1750 RPM. For pressures below 650 PSI, this will produce about 13 GPM at 1750 RPM. The electric motor horsepower should be fine for this pump at high pressures.

This pump uses a MAG 1 AW ISO 32 Hydraulic fluid or equivalent.

To get a 3000 PSI output, this pump requires 20 HP.

Components such as hose must be the same size as the input and output ports on this pump as well as fluid capacity (3/4 of the gpm flow rate) for operational efficiency.

This hydraulic pump can be used on a log splitter with an engine that is 390cc or larger. Each of the 2-stage pumps is designed to perform at a different range of performance. The advantage of this 28 GPM pump is that it can be used for larger hydraulic requirements.

The Concentric/Barnes Hydraulic Pump has a displacement of 1.395 cubic inches per revolution at the high flow low pressure stage and .465 cubic inches per revolution at the low flow high pressure stage.