Wanted to ask for you guys to help me with an issue I have with my 279c. About two weeks ago I tried lifting something too heavy for my machine to lift. The next day went on to do a job and discovered that I had lost a tremendous amount of bucket lift and curl power. Everything else was fine including pushing power. Called cat and of course they want me to bring it in and have them look at it. The tech I spoke to says that it is probally a damaged relief valve that is allowing hydraulic fluid to bypass back into the tank. Does this sound normal to you guys and Have any of you ever tried replacing the valve yourself or is this something I need to let cat look at. Also the machine runs and operates well except for this problem. Thanks Chuck...
So what is the pressure you are able to obtain at this point in time?
Also possible you blew out an O-ring on a relief valve or some such, it happens.
Thanks guys, Mike I don't know what pressure I have now for I don't have gauges to check it.. I know that is probably the best and first thing I should do... Lantraxco, makes sence to me.. How hard or difficult are the relief valves to get to? Also the cat tech said that they where separate hydro pumps for the tracks and the boom, Do you guys know where this relief valve is located on the machine?? Thanks Chuck
Let's start from the basics........Serial Number..?
297c Cat 297c mtb02247
Actually the S/N is MBT02247 but near enough. With the Serial Number the dozen or so options for the control valve are reduced to only one. Can you confirm your machine is High Flow..? Either way, here is the Control Valve that according to the system is installed in your machine. The main solenoid valve is #9 and it has a screen inside it #17 which may well be blocked with debris from something. The relief valves for lift and tilt are #6 (one above the other) and there is also another relief valve for the tilt function which is #7.
Sorry, didn't identify all the relief valves...........
Awesome... Exactly the information I was looking for. Yes it is high flow xps. Thanks so much man!!!!
Be careful pulling those relief valves off not to change any settings or to lose any loose parts. TBH I would pull the solenoid valve #9 first and look in the screen.