I recently pickup up an '04 ls180 with just shy of 4000 hours, really clean and runs good. when it's cold and I first start the machine, then try to move it wants to stall, like a heavy load on the engine. but once it warms up a bit, it runs fine. just needs to warm up...? here's the issue. when I move the levers the machine wants to quickly lunge forward (or back). it's hard to control it or do anything precise. like the drive motors engage too fast?? I am scarred to get too close to anything b/c it jumps so fast. once moving in forward or revers it's fine, i, no bucking, slipping, anything strange, it's just that initial push where it almost takes off too fast. sometimes seems to be less jerky if I try and take off with the right side than the left, it's still takes off fast. also if I let go of the levers while moving the machine doesn't want to stop, especially the left side. I kinda need to physically pull back on the lever to return it to neutral. very little creep at idle, I expect there to be some with a machine with these hours. the creeping isn't bad at all compared to other machines I've run. when the machine has been run for a while, the left side (which seems to be more problematic than the right) seems to be weak, doesn't even always want to move unless I return the lever to neutral and then go forward again. but on the flip side I remember the other day while digging in a pile of dirt the left side would keep spinning and even stalled the motor b/c like I said before all I did was let go of the lever and not actually pull it back to neutral. so maybe once it's hot it gets worse? also seems to not have as much power in forward, reverse seems fine. I haven't a whole lot of time on this machine, but I have a lot of dirt to move with it in the next few weeks. I want it running 100%, I know I'm not used to it being new to me, but something just doesn't seem right about it. I've run skid steers all my life I used to have a L785 and a LX865 10+ years ago. This machine just has a strange feel to it. again the engine runs great. again i understand it's old and has a lot of hours on it, and it's not gonna run like a new one. any help is appreciated, before it goes to the dealer for a big repair bill... or I just need to live with it...
Sounds like you have a pump control problem. Is the controls mechanical linkage (check for wear, looseness, or binding) or pilot (bad pilot pump, joystick, air in system, swash plate controls damaged)
Does it have a two speed system? If so, I have had problems with the shift linkage coming disconnected or getting loose and causing control problems. The pump has all of the control mechanism in it. There is a return to center valve which works on the swashplate angle control valve lever which may not be working to return it to center. The control handle operates a lever moving a valve which then controls the swashplate angle with a built in cylinder. It may not be smoothly moving the plate, causing the jerky action. Look on New Holland's website and pull up the parts page. There is a complete breakdown of the pumps which will give you a better idea of what you are dealing with. I have worked on two machines several times and the problems have always been the pumps, controls, or on one, the two speed control which is external. Forward should work as well as reverse as it is merely changing the oil routing and flow direction between the pump and motor. You may also have a charge pump issue which is a gerotor pump located in one of the pumps (don't remember which one) not keeping the system charged and pressurized. The loading problem may be in the parking brake setting as they screw in when turned to clamp down on a set of plates in the motors. Minor pressure from incorrect adjustment can cause them to self apply and lock down.
thanks for the help. the machine is NOT a 2 speed. I looked under the seat and all the linkages look there and in tact, without excessive play. as far as digging inside the pump(s) themselves I've never worked with such things and don't feel too comfortable tearing into them. so the problem most likely is in the pump(s), the drive motors are ok? I guess b/c of the number of hours on the machine it's gonna need some work... I probably need to have all the controls and linkages adjusted correctly first, then it would be nice to have the system pressure checked. could it somehow be too high pressure?
First off, the charge pump is in the right side drive pump. Of all the problems I have fixed on the two I have worked on, the motors haven't been a problem. The pumps are actually easy to work on, just difficult to get out (tilt loader over (use another skidder )). I have had to fix the control mechanism on both of them. The latest was while having the engine out for a broke crankshaft???, a pin in the control lever (P# 20 on servo pump page) had broken, giving no operator control. If I recall correctly, one had the key sheared out in the gerotor charge pump andthinking back, it may have had some of the same symptoms. The hydrostat system could work as a closed system but to provide some leakby for cooling, lubrication, and anti-cavitation, it uses a charge pump. I don't know what pressure it should run but it won't be very high (others on here may know). Pumps and motors are Eaton. As long as your control links are tight, adjustment won't matter too much for testing purposes.
ok thanks. I have access to another skid steer and backhoe to lift the cab if in fact I do try and tackle removing the pump. so all the problems would be in the one right side (sitting in the seat right) pump? I guess worse case scenario would be I need the pump(s) rebuilt? I'm gonna go and try and find those schematics now so I can visualize what you are talking about!
If you do have to tilt the cab, raise loader and safety lock it, unbolt it at the back and remove the rear of two large bolts at front base of cab on both sides. I have a hole in my pallet forks so I used a clevis and short chain around the quick tach plate bar to pull it over then let it down. Took all of 3 minutes to pull it over and less to put it back after disconnecting all lines and removing air filter. Right drive pump will be on right side setting in seat. If you can work on much of anything mechanical, the pump isn't anything to be afraid of. Just keep everything clean. I don't have a manual as they are expensive, just been willing to tear into them as long as I have some breakdown pictures.