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
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?
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
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.
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.
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
Are these pilot controls? Would you have been using the auxiliary hydraulics for anything lately?
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.
Yes but there are no active codes or events on computer right now
And yes been using auxiliary hydraulics every day had grapple bucket attached when this problem started
What about Logged Codes or Events.?
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.
What happens when you use the grapple, does it also stop the whining from the pump?
Sounds like you may have a switch or solenoid sticking somewhere.
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
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
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
Sounds like a piston pump with a stuck servo or false signal causing the pump to stay stroked up when it should destroke.
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
Anyone had any experience with rebuilding these pumps thought I’d try myself unless there is something complicated I’m not aware of any help would be nice
Swash plate just seen phone changed spelling on me in previous post
I have experience in rebuilding some pumps with swash plates and wish I didn’t. Lol They can cause some anxiety but really not that bad. One thing that concerns me is if a swash plate is sticking, it’s usually caused by wear on the pivot bearing and at that point, the whole pump is suspect. I have a Char Lynn drive motor on my bench at the moment and it needs seals and a front shaft and bearing, which are a sealed unit. The cost for the shaft and bearing from Eaton, exceeds the cost of a new unbranded drive motor, never mind the expensive seal kit.
Apart from the fact that there are no repair parts shown for that pump - no issues. See the attached. There is a replacement control valve listed for the piston pump and a seal kit for the gear pump and that's it. The pump group was upgraded after TAW05991 (so well after your machine) to Part Number 487-6181. "The new pump group has improved piston and swash plate springs to improve the reliability of the pump." To install the latest Part Number on your machine will require some other parts (a new hose and an elbow) apart from the pump
Ok thanks everyone for all the help and knowledge guess I will get a new pump coming was hopeful that it would be something simple or cheaper but that seems to never happen lol thanks again for all the help
If you get the latest 487-6181 Part Number of pump and want the installation instructions for the update, just ask.
One last question before I order pump and spend ton of money what are the chances of the pump control valve on bottom of the pump could be bad would this not cause same problem or is that not right and is there way to test it
On my 248b, changing the valve did not not cure it. On ours, if you just slightly bumped the pilot control, the pump would destroke.
Ok good to know thank you I am about to order $3800 pump and just trying make sure it’s not that valve instead it is a lot cheaper and would hate buy pump if valve was all I need mine is all working perfect until you release the joystick or shut auxiliary off then it won’t destroke it build pressure against control valve and pulls engine down until you move left joystick and give pressure place to go was pretty sure it was swash plate in pump but just making sure it’s not this control valve before I buy pump
If you don’t mind some downtime why don’t you take the pump apart before you order the new one. Other option is take the pump off and get someone to inspect it for you.
Unless the machine is needed immediately, I agree with the idea of taking the pump off and inspection. There is no core and you will have to make sure everything is super clean, to avoid contamination. You will have to get plugs and caps, might as well use the downtime, to get everything ready. I take it, you are going OEM and not unbranded?
OEM don't offer a Reman pump assembly which quite surprised me. The problem is no internal parts are available if anything is found to be broken - swash plate springs maybe.? See my earlier comment regarding the pump P/N upgrade. It may be work investigating the possibility that a reputable aftermarket supplier offers a Reman for this pump.
Or you could find a pump servo valve has come loose and screwed out of the housing causing it to stay stroked up. You might get away with just screwing it back in . Sounds like a lot of stroking and screwing. Better call Vetech63
Anyone got a recommendation for aftermarket pump for this that might save some money without sacrificing quality
Found the problem broke pump in half it was obvious
Guessing that’s the servo and it was broke and stuck against swash plate holding it fully stroked
That pump ain’t A swishing and a swashing no more. Good Find.