Komatsu PC210LC-7 Hydraulics non operational

[Oldboy]

Komatsu PC210LC-7 Japanese build
We replaced the seal kits in both boom lift cylinders and ran the machine briefly - all good
We then removed, resealed, replaced the dipper arm activation cylinder on the top of the boom- not good
This cylinder retracted then the hydraulics would no longer activate ; topped up the hyd oil - still no action
Checked all solenoids, power to all. Bled every point we could including lines thinking air has entered the system but to no avail.
Put some air pressure into the Hyd tank as someone recommended but no change.
Where we are at now : you can hear the hydraulics engage and you get very very slow movement of the bucket crowd but only a few degrees. its like there is very low pressure. Wont drive, lift the boom more than an inch or 2 and wont slew.
Any ideas would be welcomed, thanks Michael.

 

[funwithfuel]

First thing I would do is pull that cylinder down and disassemble for inspection. Then I would trace the dipper cylinder lines down to the control valve. Remove those spool caps. See if there is anything holding the spool off center. If you don't find anything, remove the hoses to the dipper cylinder, see if there is debris in the port. Let us know what you find.

 

[uffex]

Good day
This machine has a load sensing system could have an issue with pump signal.
Kind regards
Uffex

 

[Oldboy]

Good day
This machine has a load sensing system could have an issue with pump signal.
Kind regards
Uffex

thanks mate. Would that mean a Komatsu laptop/ software to remedy ?

 

[Oldboy]

First thing I would do is pull that cylinder down and disassemble for inspection. Then I would trace the dipper cylinder lines down to the control valve. Remove those spool caps. See if there is anything holding the spool off center. If you don't find anything, remove the hoses to the dipper cylinder, see if there is debris in the port. Let us know what you find.

Good day
This machine has a load sensing system could have an issue with pump signal.
Kind regards
Uffex

First thing I would do is pull that cylinder down and disassemble for inspection. Then I would trace the dipper cylinder lines down to the control valve. Remove those spool caps. See if there is anything holding the spool off center. If you don't find anything, remove the hoses to the dipper cylinder, see if there is debris in the port. Let us know what you find.

First thing I would do is pull that cylinder down and disassemble for inspection. Then I would trace the dipper cylinder lines down to the control valve. Remove those spool caps. See if there is anything holding the spool off center. If you don't find anything, remove the hoses to the dipper cylinder, see if there is debris in the port. Let us know what you find.

Thanks for your suggestion, Ill do this if we cant find any other ( simpler) cause for the problem. Much appreciated Michael.

 

[funwithfuel]

thanks mate. Would that mean a Komatsu laptop/ software to remedy ?

Komatsu doesn't require a proprietary laptop and software. Nearly everything is accomplished through the display screen.
Search equipment consulting services on you tube. This man has gone through the trouble to explain so much about accessing the info available to you. (Thanks John C for that)

 

[Oldboy]

Komatsu doesn't require a proprietary laptop and software. Nearly everything is accomplished through the display screen.
Search equipment consulting services on you tube. This man has gone through the trouble to explain so much about accessing the info available to you. (Thanks John C for that)

Thanks again. I noticed this on the screen today, not sure if it is relevant. We have an ops manual on order which should explain when it gets here. Symbol appears to be a fluid reservoir and a timer symbol next to it.

 

[funwithfuel]

That's an older display, not quite familiar. I would say oil level or pressure in the engine.

 

[uffex]

Good day
This may help.
Kind regards
Uffex

 

[John C.]

Usually if there is an electrical problem, the alarms would be screaming and a light would be flashing at you on the monitor panel. There is all kinds of troubleshooting stuff in diagnostics that you can check. I don't have a video on the Dash 7 machines but do have one on the Dash 8. The difference is that you press and hold the up triangle on the panel and then push 1, 2 and 3 in order and the system will go into the service menus. Here is a video of doing it on the Dash 8 machines. On those machines you push the number 4 and then 1, 2 and 3.

You can check all the electrical switches from the monitor panel. Make sure the hydraulic shutoff switch is working. It is odd that all the hydraulic functions stopped working at one time. You should check that the hydraulic lock out on the left side console is working properly.

 

[Kobelco ireland]

Sounds like something got stuck in main relief valve. Remove it, inspect it and refit

 

[jhonygee]

Sounds like something got stuck in main relief valve. Remove it, inspect it and refit

This guy is absolutely right. It was the first thing I thought about.

 

[Oldboy]

Komatsu PC210LC-7 Japanese build
We replaced the seal kits in both boom lift cylinders and ran the machine briefly - all good
We then removed, resealed, replaced the dipper arm activation cylinder on the top of the boom- not good
This cylinder retracted then the hydraulics would no longer activate ; topped up the hyd oil - still no action
Checked all solenoids, power to all. Bled every point we could including lines thinking air has entered the system but to no avail.
Put some air pressure into the Hyd tank as someone recommended but no change.
Where we are at now : you can hear the hydraulics engage and you get very very slow movement of the bucket crowd but only a few degrees. its like there is very low pressure. Wont drive, lift the boom more than an inch or 2 and wont slew.
Any ideas would be welcomed, thanks Michael.

Update: Our plant mechanic spent a few hours on the machine this week. He disconnected 2 small hoses to the pump and has everything working in terms of functions. We have now walked it to the workshop and I hope he can do a few more hours next week actually sorting out the problem. Sorry I cant give a technical reply to what's been done but I will once he gets back here.
thanks everyone for your help so far.

 

[Bruce Craven]

Update: Our plant mechanic spent a few hours on the machine this week. He disconnected 2 small hoses to the pump and has everything working in terms of functions. We have now walked it to the workshop and I hope he can do a few more hours next week actually sorting out the problem. Sorry I cant give a technical reply to what's been done but I will once he gets back here.
thanks everyone for your help so far.

any update from Mechanic about what else he did and the result afterwards. I have a machine with the same issue.