I recently went to work for a county road department. I was very fortunate to be given the newest machine a 08 CAT 140H. I was a little surprised that the new guy would get the newest unit. After acouple weeks I found out that the other guys didn't want the machine because it didn't have any hydraulic power on the right side pressure down. Not a problem as long as your just grading the gravel roads, but the first time I got myself into a soft spot & tried to lift myself out I found the problem. The machine wouldn't lift itself off of the ground to jack myself out, so I had to call the other blade operator to come pull me out. I later found that if I tickled the left blade control down while pushing the right blade control down it would finally lift itself. I found that out the first day I needed to put the chains on to plow snow..........Any suggestions or advice:beatsme. Cat replaced the left control valve saying it gets the oil first & then feeds all the other valve going right :bash& the poppet valve & spring were piled up in the valve bank. But it is still weak on the right side:Banghead. Thanks in advance. I've spent several hours reading some of your posts & have posted a few thoughts myself. I really appreciate finding a place that is like FACEBOOK for dirt stiffs:drinkup. Is it 5 yet?
I would check the resolver circuits first...I had problems with those before. The springs breaks apart and disapear or the seat gets pounded out of shape.
Alberta, Thanks for the quick repy!! Cat replaced the left hoist valve @ 1850 hrs because of the damage that had been done to the valve & seat & probably because it is still under warranty. The mechanic spoke of the resolver curcuits at that time. The machine went back in for some other repairs @ 2280 hrs & I complained that the right side still didn't have any power down so they dissasemble the left hoist valve & replaced the spring and poppet valve in the new valve because it was wadded up. What do you suppose is causing this problem to reoccur? The machine today has 2910 hrs and is acting just the same way as it did @ 1850 hrs. I think cat is stumped. It would be nice if we could give them a lead.
You said it was an 2008 140H or M series: conventional controls or joystick ?
2008 140H conv. controls
Okay. The resolver problem would be on the right valve stack. The offending valve is the one that has good hydraulic "power". Any valve/control that is after that one would be "weak". The best way to find out is to tap into the resolver line with a pressure gauge and move the levers one at the time. The bad circuit would be the one that cause the pressure reading to go back to specs.
I'm assuming that the hydraulic circuits are similar to the 14H.......
If I remember right the mechanic had told me the same thing about the problem from the beginning, Then when we went in to pick the machine up he said the left hoist valve was the first in the resolver stack (and that was the spring & valve that were damaged) and that was why all of the other valves downline ie... right of the left hoist valve weren't getting the full amount of oil or pressure when activated. I am going to take my computer down to cat with me when we take the unit in for the 3000 hr checkup & show him your post. If you have any other suggestions I would really appreciate them & I think the mechanic would too. Thanks, Alberta
Im headed out to feed the cows, will be back in a few minutes. Thanks woops had to wait 120 seconds to repost. I'm back
Lost Signal Pressure I had a 16H with just over 1000 hours that had a crack in the compact valve casting. Performed fine when it was cold, but as soon the machine got warmed up it would lose some of the signal pressure through the crack. When ever I went to backslope with the machine on the right side I could barely pick the moldboard up. I would pull on the ripper control, which was up against the stop to signal the pump. As soon as I pulled on the ripper and signaled the pump up the right side would come. I also had a 14H where the resolver ball popped back and got stuck inside the spring. Same effect; couldn’t pick the right side of moldboard up when I had the lift linkage rolled to the far right. Same 14H had a broken spring behind the flow compensator or balancing valve inside the circle drive compact valve. It’s your “Signal Pressure” that’s being lost. You are trying to send a signal to the compensator on the side of the pump, which tells the pump to stroke up, but the signal is being lost/leaking some where. Like Alberta said, either a broke spring, ball stuck in a spring, pounded out seat or a crack in the compact valve casting. All the H Series used the same compact valve casting; from the 120H to the 24H. It was the stem, which was the unique part depending on machine and implement. Good Luck, Randy
Resolver Valve problem Randy, Thanks so much for taking the time out of your busy schedule to relay your past experiences with this problem. You mentioned a problem with the circle control valve that brings to light a second problem I was going to post, but it may be related. The circle breakaway slip clutch seems to be malfunctioning (premature breakaway) & we have plans to have Cat R&R the clutch pack & adjust it @ the 3000 hour checkup. Is it possible the right side breakaway of the moldboard could be hyd fluid leaking back through the circle contrl valves & not the slip clutch releasing prematurly. Even while plowing snow if I hit a small drift with the right side the blade breaks loose & spins back to the tire. Damn aggrivating & probably pretty dangerous. The left side circle slip clutch (has to be the same clutch) functions properly with no premature breakaway. The mechanics have continued to blame the problem on the fact we have 2 foot extensions on each end on a 14' moldboard. But have no explanation as to why the left side doesn't have the problem. Thanks for posting the photos. Especially the rig & housing moves. Almost surreal thinking they being supported on a roadbed of ice. Have a great 2 week break @ home. I'll keep you & Alberta up to date on the outcome of our problem. Thanks again to you & Alberta for your suggestions for solving this problem. I think I can forward this entire discussion to our Cat shop to give them some new direction to look to solve this problem. C Ya, Dan (Patrol Man) This will be my signature when Steve allows me to have a signature. I'll relate the story behind the name another day. Won't post. Will retry.
hi goodearth 13 Have you checked the standby pressure?I had a machine with similar problem.We did pressure checks and the standby pressure was out of spec.We set the pressure to spec and it has worked fine since .You might have other problems but i thought i would mention my experience.Good luck
Grader09, Thanks for the suggestion. I think I remember the mechanic mentioning checking the standby press & it was ok. It was the resolver valve & spring stackup that caused the problem both times so far. I am going to take all of this information in to the Cat dealer to read through. It will probably be at least a month before I get the 100 hrs on the machine to get to the 3000 hr checkup. Depends of the amount of snow we get, and the ambient temperature we have. We've actually been grading the gravel in the afternoon. Kind of nice to get off shop duty & sign detail. Thanks to everybody that have replied to this problem. I really appreciate the help. Never had access to such a wealth of knowledge until I joined HEF. Like I said before it's the Facebook for "Dirt Stiffs". C Ya, Patrol Man (Dan) Goodearth13 grader09, Does the grader 09 designate you are "9" man in Colorado?
CAT 140H HYD Problem Thanks to everyone for helping with this problem. We will be taking the machine in for the 3000 hr checkup & would appreciate any other suggestions anyone has. I'm pretty confident that the mechanics will be able to find & solve the problem with this machine with the suggestions from Alberta & Randy. Thanks, again. Patrol Man (Dan) goodearth13:usa
Sorry i have the same sumptoms on my 143h. Where is this valves to check?