Cat 247b how to lock the aux hydraulic to stay running Jerome Madson
How are you trying to engage the Aux Hydraulics now and what is the machine Serial Number.?
Rotate the switch and hit the top right button on left joystick
It’s a 2010 247b
Sorry machinery doesn't work like vehicles with model years. We're going to need a Serial Number, MTL-something I would imagine. The title says "Aux hyd. on 247b won't stay running". By that do you mean the Aux Hydraulics actually start up but then stop again when you release the thumbwheel roller/push button switch.? Have you tested anything yet.?
Yes it starts when I roll it forward and stops when I release it. Can’t get it to stay running
That's weird. Do the aux hydraulics also stop if you release the button on the LH joystick while still holding the thumbwheel rolled forward or back.?
I’m not sure where to start checking
As long as I hold the roller it runs
This is how I think it works. I'm not 100% sure, maybe someone else can confirm. The roller signal tells the ECM to energize the auxiliary hydraulics. When pressed, the button on the LH joystick provides a "latching signal" to continuously engage the aux hydraulics. I would suggest to find the 12-pin wiring harness connector underneath the LH joystick. Unplug it and use a multimeter to check the continuity between Pins 5 & 6, you should find it is open circuit. Press the front RH button and you should have continuity. Do the same test for the rear RH button between Pins 5 & 8. Post back with what you find.
Ok I won’t be home till next week and I’ll check this out thank you
Meantime I'm trying to confirm that is definitely how the system works. If I find anything different to the above I'll post it up.
i cant get my continuous flow switch to work either. Im just looking for some ideas does this have a fuse or relay that can go bad. I don’t have the operation manual and doesn’t tell me which each fuse is for. Any info would be great. Thanks advance
Confirming what I posted above. This is definitely how it works. The thumb roller turns on the system, the press-button on the LH joystick provides the latching signal. First need a Serial Number to identify the correct electrical schematic for your particular machine. I can send that to you once we've identified the correct one. I'll post up the fuse layout as well once we have a S/N. Does your Continuous Flow not turn on at all, or it turns on but won't stay on.?
247b Mtl01923. The aux. Hydraulic run with the rocker switch but when i hit the continuous flow button ( on the left joystick, lower left button as far as my schematic shows) and release everything they wont stay running. I am the new owner of this machine and don’t know if they previously worked.
I’ll send you a schematic but the snip above will work. First thing you need to check is that the push-button switches marked C1 & C2 are working correctly.
am i just checking to see if there is power there. From the line digram it looks like those have nothing to do with the continuous flow switch?
All you’re checking for at this point is that the switch contacts close when pressed and open when released. So open the 12-pin connector and check for continuity between pins 5&6 and 5&8.
Effectively continuous flow depends on two signals. You have the first one from the roller switch, but it appears as though the "latching signal" from the LH joystick push button is missing. The LH joystick C1 push button sends a voltage to pull in the C1 continuous flow relay. The C2 button sends voltage to pull in the C2 relay. I sent you an electrical schematic. Check your messages.
i was able to check the left joystick buttons out , c-1 and c-2 work along with the continuous flow had horn they all ohm out the same amount so I take that as working. the one thing I did notice was that if I am holding the roller switch in and hit the continuous flow switch multiple times (3) the hydraulic flow stops (so it is doing sone thing) and then I have to reset the roller switch to get flow again. I also flipped the hydraulic hose on the implement so i know both sides of the roller switch works with flow Does the latching signal go to a relay or solenoid that i can check or straight to the ecm?
Follow the wiring on the schematic from the C-1/C-2 push buttons. I think they both go to relays but not 100% sure.
At the LH joystick. 1. With the key ON, do you have power on Pin 5, wire #120 yellow.? (Measure between Pin 5 and machine frame ground) 2. Press button C1. Do you have power on Pin 6, wire 781 Pink.? 3. Press button C2. Do you have power on Pin 8, wire 782 Grey.? 4. Follow wires 781-PK & 782-GY on the schematic. They will lead you to Grid G-8 where you will find Relays C1 & C2 located on fuse block #2. See if these relays pull in when you press C1/C2 respectively.
thanks will check tomorrow, does the cont flow switch go to a relay or ecm
I was able to check relays c1 and c2 both working suppling 12.3 volts to the round plug sitting above the auxiliary hydraulic hookup left lift arm, pin letters c & d. Let me note the electrical plug does not have any jumper wires in the dust cap and this implement ( brush cutter) does not have any electrical hook up just two hydraulic hoses
Sorry this on fell through the cracks. I also have to apologise I was sending you the wrong way on the AUX side. To activate continuous flow to the AUX hydraulic system you need to roll the thumbwheel in either direction then straight away press and release the continuous flow button on the LH joystick. That is the button on the LH side of the stick directly behind the horn button.
The hydraulics run forward and backwards that all works we just can't get them to lock on to continues run postion so we can take our finger off the thumbwheel, all switches work going to the ecm it just won't lock to continuous run, so we went to Cat and they checked it out with Cat ET and the ecm is telling them it is getting a signal to lock in to continuous run but it does not do it
Could the valve spool be loose where it doesn't lock in position?
I don't think so the flow is controlled by a electric variable solinoid it works on thumbwheel it just won't lock . I believe it is not getting a locking signal from the ECM
The "locking signal" is sent to the ECM from the Continuous Flow (rear LH) button on the LH joystick. Did you confirm that side of it was working.? If you disconnect the 70-pin connector at the Machine ECM there should be continuity from Pin 39 (wire # P993 Orange) of that connector to machine frame ground when the Continuous Flow button on the LH joystick is pressed.
I have had a customer with a 247B also that could not engage the continuous flow, turns out they just weren't releasing the thumb wheel fast enough, if you hold it for a split second too long after tapping the continuous flow it won''t engage.
sorry for the delay, we've had to put the machine back into production we will attack the problem later, thanks
Did you ever figure this out? I'm having the same issue.
The relay in the ecm was not working properly. Still trying to find a replacement one or i might just install a locking switch to turn it on and off with. That is in parallel with the rocker switch.