Hi, i have a 850c II, and it wont move front or forward with joystick, but if i use manually the pcp valves on the front and back pump the ones under the cabin then the track move, if i use the pcp that are on each final drive they dont do anything, now what i do know is that somebody put 12v directly to does pcp valve on the final drives, what i have read is that does pcp may be damage because the only use a max of 5v, is there a way that i can test does pcp to see if they are damage?
Welcome to HEF emarr . Serial number ? Damaged motor PCP’s shouldn’t shut down the transmission. Any service codes ?
Ok serial is T0850CX899052 F636 F437 F645
F645 is hydrostatic pump speed sensor wiring open circuit which is causing the transmission shutdown. F636 is right and left motor speed sensor wiring short to ground F437 is fuel temperature sensor/ circuit fault . The link below has a hydrostatic pump speed sensor to transmission controller wiring schematic along with wiring diagnostic checks @mg2361 . JD 850c 2001 - Series II Hello, As of writing this I will have to update with the serial # but the issue I am having is dozer will not move at all, throwing code F640. Thanks. HeavyEquipmentForums
Now i have F653 and F437 codes
F653 is for neutral start switch wiring open circuit . F437 is fuel temperature sensor/ circuit fault. . FYI, the Transmission and Engine service code list is also in the Operators Manual .
How i can troubleshoot the F653 or were is located if any idea
https://partscatalog.deere.com/jdrc/sidebyside/equipment/67497/referrer/navigation/pgId/77024947 . .
Hello, well now i manage to move, but is not movin like it supposed to, and the track speed switch does not let me go faster or lower, is in the lowest right now wish is one, when i try to move it goes all diferent direction but the one that im trying to go, and went go in reverse is reallly slow like no power at all
Any service codes ?
655
F655 , is for Neutral Start Switch Input Wire Short or Switch Short or Sensor Not Moved through Full Travel During Calibration . The result is transmission operates at very slow (creep) speed.
Okok, o guess i will work on checking does wires tomorrow, thank
Hello, im back, now is running but is going left when turning right, can that be fix with calibration? No codes
Hello, the calibration manual indicates that put the rpm on 1500, but the lowest it goes is 2000, is that normal?
Nope. Need to get your rpm issue fixed before you can calibrate.
Ok, and what is the lowest that machine suposed to go on rpm?
900
Is there a way to fix that?
Follow the throttle cable down to its end. You’ll find a linkage that actuates a throttle position sensor. If all the linkage looks in place and functioning , remove the sensor from the linkage. With the sensor wire harness still connected , manually rotate the internal hub of the sensor and see if you are able to control the engine speed. https://partscatalog.deere.com/jdrc/sidebyside/pin/T0850CX899052/equipment/388906/referrer/navigation/pgId/400830034 .
Ok, i will try that tomorrow, thank you
Hello, any idea were i can buy the pcp for that equipment?
Pump and motor PCP are the same number. Reman part # AT189678 Does Deere not have stock ?
AT189678 Parts For Sale | MachineryTrader.com AT189678 Parts For Sale | MachineryTrader.com at MachineryTrader.com www.machinerytrader.com
RFP-AT186588 | RFP-AT189678 | John Deere Hydraulic Pilot Control Valve RFP-AT186588 OEM pressure control pilot.Dual coil, 4 wireDeere does not sell these new any longer. Deere 750C & 850C (S/N -883331), 700H, 750C-II & 850C-II (S/N 883332-) Click here for reman option! www.riverfluidpower.com . AT186588 was the original PCP part #
Well, after finally work with the pcp, now it say tha the trans oil temp hot.
Is the oil actually hot ? or is there temperature switch /wiring issues. Have you measured the actual transmission oil temperature with a heat gun when the warning is active ?
Yes the oil is hot, i have not chek with a heat gun but i know is hot because it melted the hydrologic measure tube on the back of the tank, the one that tell you until were to fill the tank
Have a good look at the transmission oil cooler core for plugging with dirt /debris. I suggest to remove any shrouds, guarding etc. so it can be pressure washed well. There could also be issues with the oil cooler bypass valve not sending the proper oil flow through the cooler.
Ok, i will check tomorrow, were is located?
https://partscatalog.deere.com/jdrc.../pgId/77024970/partnumber/AT186410/callout/37 . .
Hello, is that the valve?
Yes , it’s the transmission oil cooler bypass valve
Is there a way to test it, or just replace it? Or any acreen to chek
You could take it apart and check it for debris, stuck spools or broken / collapsed springs. https://partscatalog.deere.com/jdrc/sidebyside/equipment/67497/referrer/search/pgId/77025012 . .
Hello, i turned the machine on, in parking for about 20 minutes and the hydraulic transmission tank got hot a lot more than the one next to it, that could be the valve right? Or is there any other test that i can do?
If the transmission oil only is getting hot under “no load” I would suspect there is something else going on. When the park brake is released do the track (s) creep in any direction ?