How’s it going guys, I have an old 444 loader, it has no steering, won’t go into gear, and the bucket barely lifts at all, last mechanic to touch it replaced the pump, he didn’t even change the filters when he did it. I changed steering filters on it along with the return filter in the hyd tank. The suction screen was a disgusting mess, I have a new one coming Thursday but it’s not making sense to me why the loader won’t go into drive or reverse because of that. If this were a cat or Komatsu it would have been fixed yesterday but I am new to the jd loaders. In my mind it seems like something electrical. Thanks
Welcome to HEF korbind96 . What model of loader , just a straight 444 with no letter designation ?
Correct, it’s pretty old
Which hydraulic pump did the mechanic change, the one below the radiator or the one below the operators seat ?
It’s A. I don’t know them. I worked on J.
Does it have remote torque converter and the drive line to transmission? Like I said - I work on “J” mostly
Put transmission in gear or try to operate steering - and look whether drive line between engine and transmission stop turning
The one below the radiator
I will have to look at that tomorrow
Brief component layout of the machine , - the closed center steering and service brake functions are supplied by the hydraulic pump mounted under the radiator. The pump is supplied oil from the transmission. The pump is driven by a coupler on the front crank pulley. - the open center loader functions (boom and bucket) are supplied by the hydraulic pump under the operators seat. The pump is supplied oil from the hydraulic tank. The pump is mounted to a flange on the transmission charge pump. . Off the engine flywheel housing is a short driveline that powers the torque converter/ transmission, make sure it is turning. Check the oil level in the transmission with the engine running. Is the oil clean and with no burnt smell ? Check that the transmission clutch cut off control knob is ”in“ . The knob is on the vertical panel just below the operators seat. What’s the dash mounted transmission pressure guage reading with engine idling ?
That helps me a bunch but also none at all as I’m not next to the machine haha, I have a feeling the mechanic before me didn’t get flow off the pump and ruled it out, a little understandably. But from my understanding on this model the transmission and other hydraulics require separate pumps and separate oil, I can’t see why the transmission pump would send oil to the other pump, when there’s a suction screen in the hydraulic tank going to the acc pump. Especially when it says do not run the same oil in the transmission as to the acc pump in the owners manual, with that being said my brains hurting on why it says that, yet I have no steering, boom functions, reverse, drive, but the brakes work fine
Just so we are talking the same language. The loader pump (mounted to the transmission below the cab floor) supplies oil from the hydraulic tank to the loader control valve for the boom and bucket cylinders is shown in screenshot below. .
The steering/ brake pump (mounted under the radiator) is supplied oil by the transmission. See screenshots below showing some of the plumbing. . .
Okay thanks for the diagrams, this is a little head smashing to me as to these issues happening at the same time
Are oil levels in both reservoirs OK? IF yes, i would suggest checking splines on drivelines and couplers. Or if there any ball/gate valves installed on suction lines - see maybe he forgot to open them up.
Oil levels are good, coupled to pump under radiator is good, I will check for ball valves, supposedly they parked the loader one night, then came out to run it the next day and this problem happened, then he installed the pump and no change
@korbind96 , What’s the dash mounted transmission pressure guage reading with the engine idling ? Is the short driveline between the engine and the torque convertor/ transmission turning ?
The transmission pressure says 75 (who knows if it’s right, and no the shaft is not turning, I just got to the loader today
I take that back, the driveline is spinning, just very slowly
What other splines should I check besides the drive line connecting the engine and torque converter?
That shaft between engine and torque converter/ transmission should be turning at engine speed. There is a drive coupler in the flywheel housing made up of (5) rubber pucks sandwiched between steel plates. The rubber pucks must have failed but are somewhat dragging
Awesome thank you so much for the information, I’m going to pull that apart now
Another possibility is the splines could have torn up in # 7 or # 13 . The (5) pucks I’m referring to is # 12 Screenshot below.
Diesel Dave you were spot on. The rubbers were disintegrated inside of there
Hey Dave, I got everything back together, the booms working awesome, only issue is no steering still and it will only drive about 5 feet
Transmission oil level is good ? Replace the transmission filter looking for metallic debris. Check the standby hydraulic pressure on the steering / brake pump mounted under the radiator.