So im been searching forms. Im sorry if someone eles covered this topic. I have a cat 248b 2004 high flow. Skid steer. Running it at low rpm's its got a growel noise form the hydraulics. You can make same noise if you max the bucket out in one direction and dont leave off. Just above the idle. To 3/4 throttle. Just curling the bucket, lifting , driving is labor intensive for the machine and makes the hydraulic noise. Using the machine not being wide open sounds bad. Wide open throttle it runs like a champ. No noises. Great pressure picks the back wheel off the ground. Has good power. Controls are smooth and quick. At a idle its got little winding noise but is smooth not laboring to and move any function. Its has New t0-4 hydraulic oil and filter. The machine got about 600 hour on it. Is there a low speed relef. That sticks. Iv hear theres anti stall on cats. I dont have any manuals and have been struggling finding infomation. Any help would be great.
First up - Serial Number please That gets you a hydraulic schematic and a document explaining how the system operates. Then hopefully one of the experets will chime in. From the sounds of the problem as you describe it, the first place I'd be looking is the implement pump suction side. You say you've changed oil & filter. Did you think to pull the tank out and clean it while you were changing the oil.?
SCL00274 The machine has sat for last 3 years with a bad injection pump. I Got it going again over winter. And put 12 hours on since. ----- forgot key detail --- it quiet ,no noise at any rpm, till i put a good load on the hydraulic system. Just moving the machine around and running at speed not enough of a load. It needs a good load. But Once the noise starts i have to run it a full throttle for it to go away. And or Its always quite when i start it for the first time that day. I felt real good about tank. i did inspector it before refilling. It was spotless. No gunk, particals or anything. Other than age and the machine sitting it did not look like it needed changing.
I posted in the wrong area.