Case 1840 - Installing Hydraulic Motor

CASE 1840 - I'm re-installing one hydraulic motor after it was repaired. All hooked up and it won't turn the axles on that side. I'm GUESSING that the air needs to be bled from the oil.

So far, to bleed it I have:
1) removed one of the 1/8 pipe thread plugs from top of hydrostatic pump, waited 12 hours to get air out, put plug back.
2) loosen sensor at top of hydraulic filter, pull wire off fuel solenoid, crank engine with starter motor to purge air at sensor, tighten sensor.

I would really appreciate some tips on this before I make it worse.

Thanks,
 
That sounds like the pump is not pumping oil to that side,slacken the hoses at the motor,spin the engine over on the starter while engaging the control for each direction,if there is no oil coming from the loose hoses the pump is not pumping,either the control valve is not moving the valve,the regulator valve is stuck open or the pump is not pumping,what was the trouble at first?.
AJ
 
The machine was operating and driving fine but I noticed the hydraulic oil level going down and the chain case oil level going up. Oil was exiting the hydraulic motor at the splined output shaft and filling the chain case. I removed the motor, sent it out for repair, and re-installed it as cleanly and carefully as I know how. The pump was not intentionally drained but some oil did leak out at the fittings when I took off the hoses.

I'll try what you suggest to slacken....and check first. I'm not sure where the regulator valve is that you mention; in the pump or the motor? I downloaded a Service Manual for my pump from Danfoss that I've just started in on. Looks like there are various ports to measure what's going on in there. How much cranking can I do without damaging my pump?
 
Come back if the hoses has flow,it maybe that the motor has an issue,was the engine tone changing when you tried to move that side.
AJ
 
(quoted from post at 20:52:40 11/07/13) Come back if the hoses has flow,it maybe that the motor has an issue,was the engine tone changing when you tried to move that side.
AJ
When I slacken the -16 hose connections between the Variable Displacement Pump and the Hydraulic Motor, there's oil all over the place coming out, but the flow rate does not seem to change with control inputs.

My pump has also an internal Charge Pump that is producing about 120 psi that I measured the "M3" port. From there it goes thru a orifice and on to the Manual Control Valve. It then, depending on the valve position, exits via one of two paths and on to the Servo at the Variable Displacement Pump. One path move moves the Servo (& swash plate) one way while the other path drains; & vice versa.

I measured the pressures at the "M4" and "M5" ports, which are the two paths to the Servo. NO PRESSURE in either one; just a little dribble out.

So I now suspect a plugged orifice, or that the Manual Control Valve is not letting the oil thru to the Servo. The 1/8 NPT plug over the orifice is stucker that stuck so I'm working up the courage to open up the MC Valve.

I don't understand the connection of all this to my motor repair.
 
I meant the hoses that are attached to the motor you changed,not every hose on the power train,the way I would have removed that motor was release the pressure from the reservoir by loosening the cap,mark the hoses,undo them and cap the ends then remove the motor,to replace the motor,fill it with clean oil,put it on and connect the hoses,top up the oil the job done,as the machine was driving ok before the motor was taken off it is fair to assume that the motor or the fitting of it has an issue,
AJ
 

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