was using my backhoe when suddenly I had very weak hydraulics. good fluid level. replaced the pressure relief valve, got better for a few days. started happening again (less than 5 hrs). new filter installed. pump pressure appears good 2800 psi. in the last couple of minutes the HSC (turtle switch) stops all hyd. function when activated. any ideas? i am fairly mechanical.
check the switch , relays etc
What year in your machine? What colour is your control valve? Where are your testing your main pressure, most of the backhoes I work on here in Oz are above 3200psi
Hi Jock, apologies for no responding sooner, out of the loop. my machine is a 98 series 3. since i last posted my hsc (turtle switch) only operates in the full open mode. when i activate the hsc all work load stops. work returns when turned back to normal but requires high rpms to even lift the unburdened front loader. i have been checking my pressure at a test port on a metal pipe on the right side of the machine. as far as the color of the valve i assume its black, not red, yellow or some outstanding color.
all switches and relays appear good.
We have had problems with Precision Control machines with weak hydraulics, these have a blue control valve hence that question. These are around the 2005 era so not your machine. Do you still have strong steering or is it all hydraulics function which are weak? Your HSC drops out 1 pump, or allows machine 2 pump flow. It may be worth removing your steer priority valve and stripping to make sure its working fine. I'm thinking there may be a chance when in turtle mode all flow is going to the steering and the steer priority valve isn't working correctly, hence no oil going to the rest of the machine Also was there any metal in the filter when you changed it?
I believe we tracked it down. The loader valve is not opening completely, hence fluid is bypassing in the valve body and pressure is not reaching max. Will remove on Monday and check seals,springs, ect.
Did you get this problem sorted out? Was the loader valve the problem? As of this morning my backhoe is experiencing the exact same problems.
I have a 215s3 with about 7000 hrs. Great machine for my purposes, but the hoe cause a lot of heat in the hydraulics. Dealer says it isn't that hot and to keep using. Trouble is the sticks get stiff and sticky. Hard to move them. The hotter it gets, the stiffer they get. Why? iirc the hyd tank got to 210F, which is technically within spec according to the dealer. The way I see it, its either the pump, valves, or a cylinder. Isn't a problem with the loader, just the hoe. Ken
So where do I start to trouble shoot this? Should I check fluid pressures? What type of gauge do I need for this? I have very little experience with hydraulic systems. This problem is intermittent, sometimes its slow and weak and sometimes it works perfect. It will jump back and forth between working properly and not while digging. HSC switch and button seem to be working, when engaged hydo function slows almost to a stop. All of the different functions seem slow and weak. The steering feels normal, but that's a little harder to gauge from feel. It may be my imagination, but it seems to work consistently better after the machine has been running for a few hours. Fluid looks clean and is at proper level. The only filter I know of (in the tank) has a few hundred hours on it and looks perfect. Is there another filter? Is there a screen that may be plugged?
No words of wisdom?
Still trying to figure this problem out..... So I had a chance to play with it and see exactly how its functioning. When the problem occurs if you engage the HSC (turtle) switch and try to pull any control on the hoe it will move extremely slow or not at all. If you reverse that function it operates at normal HSC (reduced speed). Then you throw HSC switch off and the hoe operates 100% normal, full speed and power. Sometimes it works for 5 seconds, sometimes 5 minutes, seems the average is a couple cycles. Any ideas?