160clc problems. Hydraulic stall.

[Diesel Dave]

See the speed sense solenoid (Y5) valve operation from the manual in screenshot below.
Suggest to monitor the speed sense solenoid signal to the two pump regulators by tee in a guage at the speed solenoid outlet port hose.

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[imgonnadigtochynaa]

Okay. And what should I see in this test? Pilot pressure decreasing as engine rpm pulls down?

 

[Diesel Dave]

Okay. And what should I see in this test? Pilot pressure decreasing as engine rpm pulls down?

As a load on the engine increases, the speed difference between target and actual engine speed becomes less.
The pump and valve controller decreases the voltage to the speed sensing solenoid valve which increases the speed sensing pilot oil pressure to the load piston.

 

[imgonnadigtochynaa]

So the pressure on the gauge should go UP as the voltage goes DOWN?
I should have 28v no load and theoretically 0v at full stall load?

I will get the stuff at the hydraulic shop to do that test.
Today I was able to see codes on the mpdr. Program Again it had every code imaginable. 10 codes in total. I should have wrote them down, the first code was for one of the pressure sensors, so I reverted back to monitor mode to see if it was working, and it was, then back to the fault codes and they were gone?
I'm wondering if I'm having an issue with the PVC controller communicating the fault codes?

 

[Diesel Dave]

If and when the codes return , post them all.

 

[stephenrobinson98741]

Been working on my 160clc
Just went through the whole machine this spring, used it around the shop to dig a bit, and had it working great.
The hydraulics were a bit slow on the main lift at the end of the winter and I did a pump setup as per the manual when we got it back and it has never worked so darn good.
Pulled it into the shop to finish it up, did a few nuts and bolts, went to pull it out, and the hydraulics put a crazy load on the engine.
You can stall it with the main boom, and the dipper. They seem to get real hot real fast.
Oddly enough not at the pump, the pump isn't as hot as the reservoir.
The only other thing was the batteries died before we pulled it in. Not sure what difference that would make.

I plugged it into the mpdr and it shows no codes, and I don't see anything out of the ordinary?
No flashing light on the dash for engine codes.

Sounds like the pumps may be staying at full stroke or the destroke/control circuit isn't working. If it was fine before and suddenly started loading the engine that hard, I'd be checking pilot pressure, pump control solenoids, and any wiring/connectors that may have gotten disturbed while it was in the shop. The fact the tank gets hot fast points to hydraulic oil bypassing somewhere and generating a lot of heat. I'd also verify the pump setup values didn't get lost when the batteries went dead, although I'd expect a code if that happened. No codes makes me lean more toward a hydraulic control issue than an electrical one.

 

[mg2361]

I should have 28v no load and theoretically 0v at full stall load?

Technically no. The voltage varies. You most likely will be reading an average voltage at that moment in time. The speed sense solenoid is a proportional solenoid, and under most conditions, is always activated to some degree.

 

[imgonnadigtochynaa]

Sounds like the pumps may be staying at full stroke or the destroke/control circuit isn't working. If it was fine before and suddenly started loading the engine that hard, I'd be checking pilot pressure, pump control solenoids, and any wiring/connectors that may have gotten disturbed while it was in the shop. The fact the tank gets hot fast points to hydraulic oil bypassing somewhere and generating a lot of heat. I'd also verify the pump setup values didn't get lost when the batteries went dead, although I'd expect a code if that happened. No codes makes me lean more toward a hydraulic control issue than an electrical one.

The pumps definitely stroke and destroke, as they change based on whether or not the solenoids plugged in. I will check the hydraulic output of the solenoid like was mentioned before.
But I'm leaning onto it being an electrical/sensor issue.
We had some welding done on the attachment at the end of the stick when it was inside. Hoping that didn't cause eronious issues with the PVC controller

 

[imgonnadigtochynaa]

So, I attached a gauge on the output of the speed solenoid.
The gauge starts at zero or low when functioning. When the machine attempts to stall, the gauge goes to up. When it's unplugged it stays at maximum. So I assume it is working.
When doing so I noticed the engine rpm on the dash reads almost 2300.
It's never read that high before in the years I have owned the machine, when I set the pump up before I almost want to say it read something like 2250 at wot in hp mode.
I reset the pulldown to closer to 2100, as was previously mentioned by ohdeereme around 125 rpm drop individually with the tracks stalled, and it works the way it should.
Somehow I believe my speed reference on the machine has changed. I'm assuming with the loss of battery power. I've never had that happen before. I'm also unsure of the switch behind the seat and how it works. I checked the voltage on the speed dial and it reads within spec.

 

[ExcavatorPartsVincent]

Since the speed solenoid outlet pressure is changing now, I would be careful about condemning the pump, main valve, or relief valve until the electrical reference side is nailed down.

From a parts/replacement point of view, the part that would make me nervous is the behavior changing after the batteries went dead and after welding was done at the end of the stick. Before buying hydraulic parts, I would want a written baseline of:

- actual engine rpm checked with an independent tach, compared with the dash/MPDR reading
- battery voltage and charging voltage while operating a function
- ground straps and battery/frame/engine/cab/PVC grounds, especially if the welder ground clamp location was not ideal
- PVC plugs and pins for the speed dial, engine speed sensor, pressure sensors, and speed sense solenoid: loose pins, corrosion, stretched wires, or a connector not fully seated
- all fault codes written down before they clear, even if they disappear after switching screens
- speed solenoid outlet pressure noted at no load, slow lever movement, fast lever movement, and track stall, next to actual rpm

For reference, this is the kind of evidence checklist I mean when checking a main control valve before ordering one: https://primaexcavator.com/how-shou...ain-control-valve-before-ordering-from-china/

If the hydraulic side is following the electrical command but the controller thinks engine speed is different from reality, changing a main control valve or pump parts could get expensive without touching the cause.

 

[Diesel Dave]

I'm also unsure of the switch behind the seat and how it works.

The “engine speed learning“ switch is not applicable on the 160CLC.
From the manual below.
“The machine has an engine learning switch like the previous models. The engine learning switch cannot be used to change the default engine speeds and must remain in the middle position. The engine rpm dial may not change engine speeds if the engine learning switch is not in middle position.”
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I noticed the engine rpm on the dash reads almost 2300.
It's never read that high before in the years I have owned the machine, when I set the pump up before I almost want to say it read something like 2250 at wot in hp

With the speed dial at max ,
What’s the engine speed in P mode and HP mode ?
What is engine speed in HP mode with arm in over releif ?

 

[Steve Austin]

A simple test is to back probe any sensor at the positive terminal and monitor the 5 volt power supply to see if it stays constant when acting up. You mentioned many fault codes than they are clearing out if the 5 volt power supply gets interrupted that sometimes can generate a code for each sensor. It only takes one little strand of wire to ground out and kill or decrease the 5 volts. Or a bad connection or faulty PVC.

 

[imgonnadigtochynaa]

The max rpm is 2300. Like I stated before it's never been nearly that high, it sounds the exact same as before just says higher on the dash.
The arm over relief droops down to 2080, then climbs instantly to 2150 and stays there.
And as mentioned previously, it appears to be working properly with the speed sense solenoid plugged in, and not making excessive heat, I used it today for hours on end without any issues.

I'm not certain the codes weren't from me messing around. But I will tie into the 5v on the system moving forward with any other issues.
It had every sensor code imaginable when I read it. That's a very likely culprit indeed

 

[Diesel Dave]

All I was trying to determine with the engine speed inquiry was if HP mode over relief was actually working.
Sounds like it is , so good stuff !