2000 bobcat 334 operarating presure?

[buster1]

I have 2300 lbs a full throttle at hydraulic pump what should it be?

 

[SSdoxie]

Some of the pressure circuits have lower relief setting than the main relief, and there were variations of hydraulic circuits used during production of 334. Not all 334s are the same.

 

[buster1]

thanks my hydraulic are slow and are week except the travel so I checked the pressure at the pump to see what I'm working with but I don't have a service manual yet. checking out to see if any one knows correct pressure.

 

[J_J]

Do you mean psi.

My Case 1845c relief is 2300 psi.

Weak is related to psi, and speed is related to GPM's.



Hydraulic System
334
Auxiliary Std Flow 16.4 GPM
Auxiliary Pressure 2600 psi

Bobcat Historical Specifications - Bobcat Company

 

[SSdoxie]

A year 2000 era 334 will have manual (cable) control for the travel and blade valve spools. Boom, dipper, bucket, & house swing have hydraulic pilot operated valve spools. If the manual controlled functions seem fine and the pilot operated functions are slow & somewhat weak, chances are the pilot circuit pressure is low not enough pressure to fully stroke the valve spools. All functions run from same pump system so if travel speed and power is fine, pumps should be OK.

 

[buster1]

my blade barely lifts machine I was told pressure should be 4200 . I should be able to get a service manual this week.

 

[J_J]

Once again.

Hydraulic System
334
Auxiliary Std Flow 16.4 GPM
Auxiliary Pressure 2600 psi

Bobcat Historical Specifications - Bobcat Company

Adjust it to secs and you should get a little more.

As far as speed of operation, if you are putting the rated GPM, that is the best you can do.

You will gain some force by adjusting the relief to 2600 psi.

You could cheat and go higher, but that is up to you.

 

[SSdoxie]

Once again.

Hydraulic System
334
Auxiliary Std Flow 16.4 GPM
Auxiliary Pressure 2600 psi

Bobcat Historical Specifications - Bobcat Company

Adjust it to secs and you should get a little more.

As far as speed of operation, if you are putting the rated GPM, that is the best you can do.

You will gain some force by adjusting the relief to 2600 psi.

You could cheat and go higher, but that is up to you.

That is only 1 version of the 334 & is from 2003 year.
2600 PSI @ auxiliary is only 1 circuit.
Yr. 2000 (D series) has 3 pump circuit. 2 of these have main relief @ 2800 psi. include travel motors, boom, dipper, bucket, auxiliary, & boom offset. 3rd pump feeds to blade & house and supply for pilot pressure. Main relief on this is 3400 psi. Only way to test this 3400 relief is dead heading blade up, all other circuits have lower circuit reliefs.

 

[buster1]

section 1 @ 2300 psi section 2@ 2800 psi section 3@ 2500psi full throttle .

 

[melli]

SYSTEM CHECK FUNCTION TO ENGAGE CIRCUIT PRESSURIZED
TEST
PORT
TARGET
(PSI) ACCEPTABLE RANGE (PSI)
JOYSTICK PILOT PRESSURE ANY JOYSTICK FUNCTION JOYSTICK PILOT GI 435 406 - 450
PRESSURE BUILD - UP VALVE NONE - CONSOLE DOWN P3 G 600 530-670
SYSTEM BY - PASS NONE - CONSOLE UP DUMP TO TANK G 60 MAX ALLOWABLE 100
MAIN RELIEF ON MANIFOLD BLOCK SWING AND ARM P3 & P2 G 3500 3400-3550
MAIN RELIEF ON CONTROL VALVE - FRONT BOOM OFFSET P1 G 2650 2550 - 2700
MAIN RELIEF ON CONTROL VALVE - REAR ARM P3 & P2 G 2900 2800 - 2950
SWING MOTOR - CROSS PORT RELIEF SWING RIGHT P3 G 2800 2650-2950
SWING MOTOR - CROSS PORT RELIEF SWING LEFT P3 G 2800 2650-2950

Pump outlet one (Item 1) [Figure 20-50-1] & [Figure 20-
50-2] provides hydraulic fluid to the right hand travel,
boom swing and boom valve sections.
Pump outlet two (Item 2) [Figure 20-50-1] & [Figure 20-
50-2] provides hydraulic fluid flow to the left hand travel,
arm and bucket valve sections.
Pump outlet three (gear pump) (Item 3) [Figure 20-50-1]
& [Figure 20-50-2] provides hydraulic fluid flow to the
upperstructure swing, blade and boost valve sections.