Hitachi FH 150-3

[Agrimax]

Hello folks,Just joined up and rather than faff about get nowhere I thought I'd ask here. Am well used with working at tractors and rubber tyred diggers but not so much with 360s.
The above machine has decided to track on one side while slewing or working the bucket ram and that's without touching the track lever. Both track levers are sticky and don't return to centre on their own,although the springs seem to be fine. So that needs sorted! When the track turns with other functions being operated,if I stop everything and then work the track lever on it's own,the track will not move. The lever has to be pushed and pulled a number of times to regain track movement. Hope you can follow. Anyone know what the problem could be? I'm thinking maybe the seals in the rotary coupling underneath perhaps?

 

[V8Druid]

Hello folks,Just joined up and rather than faff about get nowhere I thought I'd ask here. Am well used with working at tractors and rubber tyred diggers but not so much with 360s.
The above machine has decided to track on one side while slewing or working the bucket ram and that's without touching the track lever. Both track levers are sticky and don't return to centre on their own,although the springs seem to be fine. So that needs sorted! When the track turns with other functions being operated,if I stop everything and then work the track lever on it's own,the track will not move. The lever has to be pushed and pulled a number of times to regain track movement. Hope you can follow. Anyone know what the problem could be? I'm thinking maybe the seals in the rotary coupling underneath perhaps?

Welcome boyo ....
sounds like a strange one ..... slice in the block split perhaps ?? slew is usually a very separate circuit from everything else too ?
the rotary won't have either of those two services you mention through it, so can't see how they could cross feed a track with a split o ring in the rotary ??
Crawler of that size will have very limited services through the rotary .... five or six galleries at most for the track motors .... nothing else down there, unlike a duck or a smaller machine with a blade as well ......... strange!

 

[Mogman]

Maybe the track leavers are not quite in neutral but not far enough for it to track as not enough pressure but when another service is used it can build up pressure in the pumps to track it one track is linked to two lever functions and the other track likewise (it may look like it only has one pump on the machine but it has two running from the same rotor in the pump therefore two out lets

 

[Agrimax]

Thanks folks. Will get a look this week and see why the track levers are sticky first. I assume the control valve they work, below the floor is low pressure activating the high pressure spools on the distributor unit?
Just thinking about it, the rotary wouldn't need anything else going through it right enough!

 

[Shovelhands]

Are the track levers servo operated or cable operated to the spool block?

As Mog says, one side of the pump feeds one track, the slew and the bucket operations, and the other side of the pump feeds the boom, dipper and the other track. I’d say there’s an issue in the spool block on the track circuit, it’s not in neutral for some reason? Broken return spring perhaps?

 

[Agrimax]

They're servo. Small valve block under the floor that the levers are connected to. Will check again this week as to what other functions cause the one track to work. Strange that both track levers are sticky,but I think it was just the one side that loses its function after tracking through the slew.Have to work the lever back and forth a lot of times to get tracking back.I can centre the track levers ok,but I guess the main spool may not be centreing.......Will investigate later in the week.

 

[Grifferr]

Maybe swap the 2 left servo pipes to the right and 2 right to left. See if it changes side. Has she been parked for a long time?

 

[Agrimax]

Will bear that in mind....
Gets used regularly with a timber grab mainly.

 

[Agrimax]

One of the track servo buttons was partially stuck down...! A good clean out round, a few taps and it came up again. Just gave everything a good dose of penetrating oil and it seems fine again. Simple enough in the end....... If it lasts!

 

[doobin]

Result! I love a simple fix.

 

[Mogman]

Maybe the track leavers are not quite in neutral but not far enough for it to track as not enough pressure but when another service is used it can build up pressure in the pumps to track it one track is linked to two lever functions and the other track likewise (it may look like it only has one pump on the machine but it has two running from the same rotor in the pump therefore two out lets

A result

 

[Agrimax]

You got it in one Mm. Thanks for the input.