843, charge light on

[la350]

I posted yesterday regarding this issue and it appears the charge light is "on". The wire for this sensor has never been connected since I've had the machine, I checked the wiring schematic, found the wire, reconnected it and it stays on while the rig is running and there is no power to either side wheels. Here is the timeline on this problem: I bought it a few years ago and have only put 10 or so hours on it. It had a rattle or hammering on the left side when the joy stick was moved Left side went dead, right side worked. I pulled the left side motor off, removed the hoses off the right side hoping to relieve pressure to make it easier to winch onto a trailer. Parked for 18 months. Checked with Bobcat, they said to switch motors side to side to see if it was a motor problem. Did that. Power to bucket but no power to either side wheels now. If I accidently switched the hose positions at one or both pumps, would that cause this problem? Seems like that would just make the wheels turn opposite the normal joy stick position. Any suggestions where to go next with this issue? I just want to get it operational (at least one side as I suspect possible left side chain case issues) and SELL it.

 

[Tazza]

It could be a few things... It could have been the drive motor making the noise, or even the pump. Its possible the problem has gotten worse and whatever was clunking let go.

 

[frogfarmer]

The drive motors get very noisy when they are bad. It could be they were run bad for some time and have ruined the pumps. The charge pump is a seperate section of the lift tilt hydraulic pump and may be bad or very weak as I have seen this before. Swapping the hoses on the motors will cause no damage and like you suspect will only cause directional changes ie forward stick will cause reverse movement. Charge pressure and volume need to be verified as your next step. With the motors off and the wheels in the air the wheels should turn very easily and any chaincase problems should be evident by noise or lack of movement. Also make sure it has the proper fluid level as it likely drained out over an 18 month span.

 

[OldMachinist]

The drive motors get very noisy when they are bad. It could be they were run bad for some time and have ruined the pumps. The charge pump is a seperate section of the lift tilt hydraulic pump and may be bad or very weak as I have seen this before. Swapping the hoses on the motors will cause no damage and like you suspect will only cause directional changes ie forward stick will cause reverse movement. Charge pressure and volume need to be verified as your next step. With the motors off and the wheels in the air the wheels should turn very easily and any chaincase problems should be evident by noise or lack of movement. Also make sure it has the proper fluid level as it likely drained out over an 18 month span.

I'll add one more possible cause. Left side motor and drive chain bad, moved right side motor to the left and chain still bad so no movement. Bad left side motor now on right side and no movement.
Put a gauge in the charge pressure port and verify low pressure.
843 charge pressure
Serial number 12999 and below 120-140 psi
24001 and up 180-200 psi

 

[la350]

I'll add one more possible cause. Left side motor and drive chain bad, moved right side motor to the left and chain still bad so no movement. Bad left side motor now on right side and no movement.
Put a gauge in the charge pressure port and verify low pressure.
843 charge pressure
Serial number 12999 and below 120-140 psi
24001 and up 180-200 psi

I will also have to check the bronze filter in one of the hyd blocks. The Bobcat tech reminded me that when he assisted me in the purchase of this rig that it wouldn't move. Turned out the bronze filter was plugged up with gunk. I'll check that tomorrow and if that doesn't do the trick, I'll have Bobcat come out and pressure/flow check.