Cat 289d hydraulic issues

[Sbird]

I hav cat 289d that started acting up yesterday sn# taw02801 the hydraulics are making whining sound all the time but if you use the lift or tilt it will quite sounds normal until you release joystick then it returns and causes engine lose couple hundred rpm’s and acts like hydraulics are under heavy load but soon as you move right joystick to control bucket it stops and regains power seems something is sticking just not sure what I put my brushog on it and kicked the continuous flow on to it and everything acts normal and operates perfect until you kick it off any ideas where to start

 

[HarleyHappy]

Sounds like your hydraulic filter is going into bypass.
Any other functions possibly on?
Is there water in the system.
Does the noise sound like when your pressure relief valve, when it is activated, like when you curl yo bucket all the way up, then it won’t go no more?

 

[Sbird]

All functions are off and yes that’s what it sounds like is pressure release valve activated but if you move the lift arms or activate auxiliary hydraulics it quits and sounds normal till you release button or return joystick to neutral position

 

[HarleyHappy]

I’m sure you have checked the hydraulic fluid level.
Generally when the hydraulic pump sounds quieter, when you use something, the system is in some type of bypass.
Or, something is restricting flow and when you use a function, that fluid is returning to tank, releasing the bypass.
How cold has it been and when is the last time you changed the hydraulic filter.
Don‘t get a cheap hydraulic filter, they aren’t cheap, in the long run.

 

[Sbird]

Yes, fluid level was the first thing I checked. It’s full second thing I’ve done was went to Cat and got new hydraulic filter and replaced it even though I replaced them on a regular basis didn’t see anything abnormal in the filter I took out temperatures have been hovering around the 40 upper 40s.

 

[Sbird]

And when you move the machine forward or reverse on the left joystick, it is very slow and strains the machine to move, but if you raise the lift arms or tilt the bucket while driving, it has full power until you release the right joystick

 

[HarleyHappy]

Are these pilot controls? Would you have been using the auxiliary hydraulics for anything lately?

 

[Nige]

Are these pilot controls?

No they are electronic.

Interesting the comment about the effect of operating the drive joystick along with the implements.

Do you have any way of accessing Diagnostic Codes.? That would be the logical next step.

 

[Sbird]

Yes but there are no active codes or events on computer right now

 

[Sbird]

And yes been using auxiliary hydraulics every day had grapple bucket attached when this problem started

 

[Nige]

Yes but there are no active codes or events on computer right now

What about Logged Codes or Events.?

 

[Sbird]

No logged ones either the only logged ones are old

 

[Nige]

No logged ones either the only logged ones are old

How about posting the list up and let us have a look at it.?
Who knows, someone might just spot something you may have missed.

 

[HarleyHappy]

What happens when you use the grapple, does it also stop the whining from the pump?

 

[HarleyHappy]

Sounds like you may have a switch or solenoid sticking somewhere.

 

[Sbird]

Yes it stops as long as you are using aux hydraulics or moving loader functions that’s what I was thinking is something is sticking just not sure where to look I will post the logged events and codes when I get home this evening

 

[Sbird]

Only codes and events it shows are stored one they are engine temp high which was bad heat sensor I changed 6 months ago speed sensor abnormal voltage which I changed sensor due to broken wire and dpf filter high when I changed exhaust filter two years ago and that’s it

 

[Sbird]

I’m no professional mechanic but in my mind what I think is pump has constant supply of fluid to control valve and when you are not moving any of the controls the fluid has to bypass somehow I’m guessing and whatever controls the bypass of fluid seems to me would be the problem because as long as you’re using at least one thing on control valves the hydraulics are quite and normal but when you’re not using them it is building pressure and pulling engine down and reduces power so does anyone know if my theory is right and if so what controls the bypass of the fluid to the control valve when not using

 

[Mobiltech]

Sounds like a piston pump with a stuck servo or false signal causing the pump to stay stroked up when it should destroke.

 

[Sbird]

Just had experienced mechanic tell me he had fixed this problem on similar machine and it was awash plate sticking in the pump he said one he fixed had to replace pump due to bearing but the awash plate is my problem he thinks