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330B slow stick in , slow bucket curl

Kalvin Factor

Member
Joined
Dec 31, 2022
Messages
7
Location
Ontario Canada
Having issues with stick cycle times in and bucket curling in on a 330B 6DR prefix

Checked pilot pressure
Checked RPM speed sensor throw service menu
Checked each pump individually (swing stall /each track) both are reaching 5000psi

Pilot pressure good 600psi

Pilot shuttle is below 200 psi when stoking pumps

Both pumps stroke up to 5000 psi when boom is held over relief

Checked speed times for tracks stick boom

Stick in is almost 5.38 seconds

Bucket in or curl in is 6.68 seconds curl out is 3.8 seconds

Changed the pattern valve to cat controls did not change stick speed was thinking pilot valve on joystick issue

Engine is reaching full RPM speeds are at 10 pressure checks are at 3-4 on the speed dial

PRV is reading in service mode. And to spec as well

Cylinders don’t drift or settle (no squeaking

Filters and oil have been changed well kept machine and cat lubricant additive has been put in tank few times.

Cut filters nothing in them

Any thoughts beside flow testing

No weird noises from pumps no leaks

And good power just slow if I go

To load a truck etc swing is fine and travel is fine tracks straight boom is fine.

Stick out is fine bucket out is fine
 

HarleyHappy

Senior Member
Joined
Sep 30, 2020
Messages
3,406
Location
So NH
Occupation
Welder/Mechanic
How long has this been going on? Did it just start? Any work done recently.
Must be cold where you’re at. Possible that cold Hydraulic fluid, not helping.
Does it get better or worse or stay the same after warming up?
Check lines, cylinders and pumps for excessive heat, compared to everything else. Sounds like a restriction somewhere.
 

Kalvin Factor

Member
Joined
Dec 31, 2022
Messages
7
Location
Ontario Canada
Hello sorry for late reply

7 seconds for bucket curl in time or (cylinder extend/out ) which is on the high end of cats cycle time , I’ve checked pump pressures , and cycled both pumps by stalling swing , stalling tracks out all pressures get up to 5000psi on engine speed 3 that’s with machine warm

Tracks rotate at same speed.

Pilot pressure is perfect , engine rpm/ speed sensor is working

No cylinders drop or creep down

So squeaking in cylinders

My pressure tests rule out main relief but

Im curious if pulling out stick circuit relief or bucket relief checking them and or turning them up

No banging or hammering near pumps all clamps are tight no air leaks , Hyd fluid is good , filters are new , cat hyd additive x2 added when serviced

New fuel filters and checked tank / ensured engine was getting to full rpm and reading , to stroke pumps out so it doesn’t default
Check pilot psi, 575-600.

Main relief, boom raise speed dial 3-4, should be close to 5000.

Power shift should be low in stall 180-230psi or the engine is weak/flywheel speed sensor issue

Checked that as well

The extend retract times are close to serviceable but at full rpm I feel the bucket or stick in should be a touch faster for loading trucks in KW+ and in dig it’s slow and I feel I’m waiting for the machine to catch up all the time. Or I have to show up for the stick to raise to get up over the side of the truck when loading

We have multiple deere excavators and I know they aren’t completely the same as a cat for cycle times , I’ve run a few cat
Hoes but for some reason I’m not convinced it’s right

Swing , boom up , tracks all work well no slow issue's stick out is fine , curl out on bucket is good but stick in or bucket in slow
IMG_4435.jpegResized_20251222_141853.jpegResized_20251222_101044.jpeg
IMG_4539.jpeg
 

Simon C

Senior Member
Joined
Jul 1, 2015
Messages
3,014
Location
Rocky Mountain House , AB., Canada
Occupation
Heavy Equipment Mechanic
Hello sorry for late reply

7 seconds for bucket curl in time or (cylinder extend/out ) which is on the high end of cats cycle time , I’ve checked pump pressures , and cycled both pumps by stalling swing , stalling tracks out all pressures get up to 5000psi on engine speed 3 that’s with machine warm

Tracks rotate at same speed.

Pilot pressure is perfect , engine rpm/ speed sensor is working

No cylinders drop or creep down

So squeaking in cylinders

My pressure tests rule out main relief but

Im curious if pulling out stick circuit relief or bucket relief checking them and or turning them up

No banging or hammering near pumps all clamps are tight no air leaks , Hyd fluid is good , filters are new , cat hyd additive x2 added when serviced

New fuel filters and checked tank / ensured engine was getting to full rpm and reading , to stroke pumps out so it doesn’t default
Check pilot psi, 575-600.

Main relief, boom raise speed dial 3-4, should be close to 5000.

Power shift should be low in stall 180-230psi or the engine is weak/flywheel speed sensor issue

Checked that as well

The extend retract times are close to serviceable but at full rpm I feel the bucket or stick in should be a touch faster for loading trucks in KW+ and in dig it’s slow and I feel I’m waiting for the machine to catch up all the time. Or I have to show up for the stick to raise to get up over the side of the truck when loading

We have multiple deere excavators and I know they aren’t completely the same as a cat for cycle times , I’ve run a few cat
Hoes but for some reason I’m not convinced it’s right

Swing , boom up , tracks all work well no slow issue's stick out is fine , curl out on bucket is good but stick in or bucket in slow
View attachment 354555View attachment 354552View attachment 354553
View attachment 354551
Read your whole description above. Could you have some binding happening in the pin between the stick and boom. Could a hose have been changed that has a smaller inside diameter or a restricted fitting on the hose which would not affect pressure, but would affect speed.
Simon C
 

nikthewho

Well-Known Member
Joined
Oct 23, 2024
Messages
152
Location
Delhi
Occupation
Hydraulic Engineer
Pull the stick and bucket control spool assemblies & Inspect for:
  • Scoring, scratches, or rough machining on the spool lands
  • Burrs or contamination in the bore
  • Corrosion or varnish deposits (common in older machines or with old fluid)
  • Verify spool moves freely by hand without binding
---

Your pump shuttle pressure (below 200 psi during stroking) is good, but the load-sensing margin on the stick/bucket inlet valve maybe drifting:
  • The LS compensator on the main pump may not be responding equally to all load-sensing signals
  • If the stick LS signal line has a restriction (kinked hose, partially blocked shuttle), the pump's margin calculation fails, reducing flow to that circuit
Verify LS line pressures:
  • Measure pump discharge pressure minus stick circuit load pressure during stick-in extension (Should be approximately 25-30 psi margin)
  • Compare to swing LS margin (which works fine)
  • If stick LS margin is significantly higher, the compensator isn't properly tracking. (LS pressure should be load pressure + ~25-30 psi)
---

Even though you changed the pattern valve, the proportional control electronics could be degrading:
  • Insufficient dither signal to the stick proportional valve solenoid
  • Valve driver card on the CAN module providing weak command signal
  • Joystick potentiometer drift specific to stick-extend position
In service mode, verify:
  • Stick proportional valve solenoid amperage during extend (should increase smoothly 0-10A)
  • Monitor voltage output from joystick potentiometer for stick extend axis
  • Confirm dither frequency and amplitude on oscilloscope (typically 50-100 Hz, 2-5V peak)
Before committing to spool removal, perform the flow test. This takes 20 minutes and definitively proves whether the problem is in the pump (already ruled out) or the control circuit. If measured flow during stick-in extension is significantly below CAT's specification sheet, you know spool/relief work is justified.
 

oldtom

Well-Known Member
Joined
Oct 15, 2012
Messages
216
Location
Australia
Occupation
diesel equipment maintenancesuperviser
Hello sorry for late reply

7 seconds for bucket curl in time or (cylinder extend/out ) which is on the high end of cats cycle time , I’ve checked pump pressures , and cycled both pumps by stalling swing , stalling tracks out all pressures get up to 5000psi on engine speed 3 that’s with machine warm

Tracks rotate at same speed.

Pilot pressure is perfect , engine rpm/ speed sensor is working

No cylinders drop or creep down

So squeaking in cylinders

My pressure tests rule out main relief but

Im curious if pulling out stick circuit relief or bucket relief checking them and or turning them up

No banging or hammering near pumps all clamps are tight no air leaks , Hyd fluid is good , filters are new , cat hyd additive x2 added when serviced

New fuel filters and checked tank / ensured engine was getting to full rpm and reading , to stroke pumps out so it doesn’t default
Check pilot psi, 575-600.

Main relief, boom raise speed dial 3-4, should be close to 5000.

Power shift should be low in stall 180-230psi or the engine is weak/flywheel speed sensor issue

Checked that as well

The extend retract times are close to serviceable but at full rpm I feel the bucket or stick in should be a touch faster for loading trucks in KW+ and in dig it’s slow and I feel I’m waiting for the machine to catch up all the time. Or I have to show up for the stick to raise to get up over the side of the truck when loading

We have multiple deere excavators and I know they aren’t completely the same as a cat for cycle times , I’ve run a few cat
Hoes but for some reason I’m not convinced it’s right

Swing , boom up , tracks all work well no slow issue's stick out is fine , curl out on bucket is good but stick in or bucket in slow
View attachment 354555View attachment 354552View attachment 354553
View attachment 354551
its not pressure but flow that increases or decreases cycl times, how much oil going in the cylinders
 
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