I'm continuing to spend all my time researching on-line, rather than in-person, as I'm too busy to get to any dealers. Now that I've narrowed it to a B-series 2320-2920 model, I'm trying to figure out my needs h.p.-wise. The tractor is going to primarily be used for FEL work and to run a MMM... but I do plan to get a generator and
chipper down the road.
When I look at the specs on these tractors, they all share the same hydraulic pumps. They all have the same output.
My question is: if I were to get a higher h.p. model like the 2920, could I run it at lower RPMs and still get similar hydraulic output as a 2320 running at full RPM? I have a 2305 and it has to be really dialed up to move the loader.
No
"Hydraulic pressure is a result of resistance to a load in a hydraulic circuit."
A "specific volume-cubic inches/centimeters" of hydraulic oil will travel through the gear pump at any given engine speed/pump rotation and that is permanent until the pump dies or becomes weak in flow.
"Hydraulic pumps offered for sale are tested for a baseline flow and pressure at 1200 rpm and 100 PSIG."
As a rule hydraulic pumps for engines in small packages are shopped and if a pump frame fits within a mounting situation it is bought and specd by the manufacturer.
Small engines sets are built from the botttom up like mining equipment and the smaller the pump the better as the hydraulic oil reservoir is very small and this is key.
Your engine is doing or could be doing a number of jobs at once
1. power steering
2. pump flow to the hydraulic circuit at rest
a pump flow to the hydraulic circuit while under load being one or both loader valves at one time, and the lift cylinder for the mower.
3. powering the alternator and its loads, charging the battery, powering lights, the cooling fan, the four wheel drive of the tractor
4. pump flow to the circuit doing work when required by the operator
5. the transmission oil charge pump is working just as fast as the engine is and that adds to the engine loading.
6. providing energy for the rear PTO at 540 rpm and a mid mount PTO through a reduction gear box.
========================================================================================================================================================================================================
You could do one thing to improve the volume and pressure and flow rate with your tractor by buying a 3 point hitch mounted hydraulic reservoir which uses an independent pump powered by the PTO shaft at 540 rpm.
The ones I have seen for sale are built on a mounting stand to allow it to be left on the ground while working too.
BUUUT you would have to:
1. buy a pump rated for the flow rate of the loader or snow blower etc.
to be sure the circuit is not overloaded with higher flow rates than the system can tolerate or was designed for.
2. change the plumbing routing of the loader to the independent pump and reservoir by adding quick connects and additional hose.
========================================================================================================================================================================================================
A generator will require you to operate the PTO at 540 rpm which is the typical rated speed to create adequate electrical power and provide it for use other wise the brushes will be burned up/and system overheat will occur.
The
chipper will require 540 rpm as the fly wheel has to be rotated at a set speed to provide usefull work energy for the knives to chip wood.
A rear mounted flail mower will operate at 540 rpm and be less of a load on your tractor and be a safer mower that will not throw objects.
It may be that you simply need just a filter change as well as getting the pump flow rated by the dealer to see if it needs to be changed.
leon
