I have a Cat 279C S/N CAT0279CLMBT03099 with 1900 hours. When driving the machine in forwards or reverse and the engine at an idle the machine will slow to a creep and eventually stop moving. If you move the left hand joystick back to neutral and then start again it will move at normal speeds and gradually slow back to a creep and stop. You can continue to put the joystick back to neutral and back to keep the skid steer moving. When the engine is reved up all the way the machine moves as it is supposed to pushes strong and never slows down. I do not have the advanced display but have an aftermarket computer I can plug into it. With that computer I have looked at codes which I have none of. I have also calibrated the left joystick, and calibrated the forwards and reverse stroke in the hydrostats. As per the advice of a previous thread I have also had someone watch the hydraulically driven cooling fan while running the machine to see if it slows down and it is maintaining proper speed as far as my eye can tell. I'm looking for any advice I can get. Thanks
You may not have the Advanced Display but can you post a photo of what you do have please. When the machine slows down does the Driver Alert start flashing.? I suspect that your aftermarket computer might be telling you porkies. What type of scanner is it.?
There is no flashing light indicating a code when the machine slows down and stops. I have a Jaltest diagnostic laptop.
Bad luck. Your machine is equipped with the only type of panel which will not permit access to Diagnostic Codes. I think there have been reports on this forum of the Jaltest product performance being less than optimum when working with Cat comms but I can’t remember any specific details. Have you done any basics such as replacing the hydraulic filter and cutting open the old one for inspection, or an oil analysis of a sample of hydraulic oil.?
I have replaced the old hydraulic oil filter with a Cat filter and cut open the old one. It was dirty inside but there was no large concerning ammounts of metal in the filter. Nothing to indicate a large scale pump failure.
That in itself is not a good sign. It doesn’t have to be a pump failure. Every component in both the drive and implement systems get the same oil from the same tank. Did you happen to take any photos of the old filter you inspected.? My next suggestion is an analysis of an oil sample paying particular attention to elements such as iron, copper, & silicon as well as the particle count, aka the ISO Cleanliness Code. My prime suspicion at the moment is internal leakage in the mechanism that strokes the hystat pump swash plates. What’s the back story on this machine.? How long have you owned it.? How/when did the problem start..?
How much is difficult to interpret as only a tiny piece of steel imbedded in the wrong place can cause problems. How about changing out the filter again and open with a proper filter cutter to examine the squished paper element. Maybe something is coming apart, would be good to rule out. Simon C
We just bought the machine and don't know any of the history of it. It has had the problem since it arrived.
OK, so it was bought with a problem. It would’ve been nice to know that earlier. That answers that question then. You need some information to go on from this point - oil analysis next, plus another filter cut as Simon suggested. I’ll forecast it now - this is going to get expensive right quick.