Daewoo 130 lcv - rotary valve/swing center issue

[jtobin34]

Hi All
I am looking for some advice on a 1999 Daewoo 130 lc v that I have just bought
I plan to use it for tidying up my farm but the one issue it has is weak tracking. When I start it up it tracks fine but when it is hot it has no power and in fact will not turn the individual tracks. I am thinking I need to reseal the centre pivot/rotary manifold according to what i am reading online, but i am a bit concerned regarding how difficult this would be.
Any body with any experience with this digger who could advise, or a service manual to guide me in repairing the unit
Thanks for any help
John

 

[Shovelhands]

Has the machine got plenty of digging power once it warms up?

 

[jtobin34]

Yes seems to have good digging power when hot
to be honest I am not that experienced when it comes to excavators

 

[Shovelhands]

If it definitely has good digging power when hot, then it would suggest that the main hydraulic pumps are ok.
It could be the track motors, but for both to be knackered at the same time?....unlikely?...

The rotary coupling is a good place to start, and is the likely cause. It’s something that you can do yourself if your handy with the spanner’s. Make sure you label the pipes and their location, before you start, take pics if necessary.
It’s a messy job, you’ll need to get yourself into the turret of the undercarriage to remove the lower pipes. Although some rotary couplings can be taken apart from the top, without the need to remove the bottom section from the machine. I really have no idea what it will be like on your Daewoo, maybe put a pic up of the rotary if you can?

Having said all that, it may be worth you finding a decent Plant mechanic or hydraulic engineer, to test the pressures for you and diagnose the fault, make sure you find someone who is experienced with excavators and knows their way around Hydraulics. This may save you chasing a fault yourself, and could save you time and money in the long run if you are not that confident yourself. If they also think it’s the rotary, then maybe get them to quote for the repairs, it may not be worth the hassle getting involved yourself.

Back to the fault, you say it tracks fine when cold? Does it track in a straight line when cold? As I’d expect, if the rotary was that worn, to the point where it would not track when hot, that it would have poor tracking when cold and definitely not want to go in a straight line.

 

[jtobin34]

Thanks for the comments and info - yes it definitely has good digging power for example at the weekend it was good and hot at which point the tracking was absolutely horrendous so I tracked over to stump from a good size tree that I had cut down recently and went about pulling it up. The stump was fairly solid and the machine was either pulling itself over (i.e the whole back was lifting up off the ground) or the whole machine was being pulled in towards the stump. Would this indicate that digging power is ok?
On the tracking question it tracks fine when cold in that she will spin herself around without the assistance of the boom/slew and will climb up a fairly steep slope and tracks in a reasonably straight line. Also the high speed tracking seems to also work fine when cold. Once it is hot it doesn't track straight at all and has zero power if I push one on the travel levers on the machine the track tries to turn but fails, the engine does not load up under these circumstances. When I push both levers together it will move the machine around just very slowly
I have got my plant mechanic on it and he is an experienced guy so I have moved the machine to his workshop - he says he wants to replace the seals in the swing center first to remove this as a potential issue as the seal kit is only €220 from Doosan. He will go from there with checking pumps and motors etc. On the track motors would you have any idea what sort of case drain flow rate would indicate the motors were bad/good. Also are there any other diagnostics I can perform on the track motors? I also want to change all the fluids is there a specific grade of hydraulic oil I should be using or one that has better stability when hot
The attached images are of the swing valve - it is very wet and oil as I had a leak from one of the high speed tracking lines which has been addressedy
Thanks for the help and advice

 

[hjwemc]

I have same problem with dh130-2 and interested how you got on