I Noticed when I have a lot of weight on bucket and swing house it doesn't stop as if when bucket empty. Is there adjustment for break.
There’s no adjustment to it. It’s spring applied and hydraulic released. The bulk of my experience is on Cat hoes but there are a couple things to check. I assume it’s controlled through the ECM like cat so there may be a delay built in there. Beyond that it could be a solenoid issue, a hydraulic issue or it’s flat wore out. How many hours on the machine?
8000
8000hrs
I might be wrong saying brake. When I swing house doesn't stop the same with heavy load as not having load.
You’re right it’s more than likely the swing brake. If you can get your hands on a service manual that would be most helpful in troubleshooting. On Cats we check release pressure to the brake. What I look at is full release pressure and if the release pressure drops like it should when you let off the control which should signal the solenoid to shut off oil thus setting brake. You can also unplug the solenoid and see if you can swing. If brake is good it should bog down and not swing. Based on the results you can then seek the reason you’re not fully releasing pressure or the reason the brake isn’t holding which would be worn parts more than likely. On a Komatsu I’m not sure where the solenoid is located. Fairly close to the swing motor I’d assume, more than likely grouped with a couple others. On Cats I’ve had issues with the relief valves on the swing and even had issues with swing cushions as well. Not exactly sure how yours is setup compared to Cat
Good day Attached is a couple of informations hope they help. Kind regards Uffex
The unit is a swing parking brake and the failure mode is to lock up. Your problem, if it is a problem or just a feeling, is in the swing cross over relief valves. Does the swing feel a little sluggish when starting out? Apparently it is sluggish when coming to a stop with a load in the bucket. At those hours you need someone to go in a tune up the systems. Check and reset the pump flows and all the reliefs and put the machine back to factory specs.
Thanks yes sluggish with load. I will have a tuneup done.
Hi All, I have a similar but different issue on a 2008 EC140B. When I slew the machine and then stop, the slew stops but moves very slowly a few degrees before the brake kicks in, especially noticeable working on slopes. The company we bought it from checked it out and rebuilt the slew motor under warranty to correct but it made no difference. They said the oil should hold the slew until the brake kicks in so there must have been wear in the motor, hence the rebuild. They were hitachi mechanics so don't think they were much help on the volvo. Is there some way of reducing the delay in the brake kicking in?
Good day Eddie The symptom you describe is normal for that type of swing transmission, the valves do leak some it is something we have to accept. If you believe it is excessive install a gauge to each side of the swing drive and with fluid at working temperature watch for how quickly the pressure leaks away when you return the lever to neutral. You could reduce the brake engagement delay buy I would suggest it is may be better to live with what you have rather than put your transmission at risk. If you need information drop me a line. Kind regards Uffex
Thanks Uffex. Not exactly what I wanted to hear though . Would that be standard play in the valves or could the valves be reconditioned to improve it? It's not bad and probably not worth changing, just when you notice something you can never unsee it.
Most ALL swing brakes only hold the machine not stop it. Gradall, Kobelco and several others that we sell all work that way. You can adjust the reliefs only thing is on most machines that also changes the swing force.
That issue sounds like there is a soft swing function installed on the machine. Some photos of the swing motor and possibly the routing of the hoses might provide some insight.
Good day Eddie If you take a look at page 3 of "Swing slew issues" posted earlier on this same thread that is what your EC140B hydraulic schematic looks like, unfortunately it is a combination of a number of leaking valves that result in the slew creep you describe. The most difficult or should I say expensive is that of the main spool & housing - reworking is not a possibility as the spool is matched to the housing further replacing the Main control block & spool may not improve the creep as a new spool may leak as bad as the one you have. The remaining valves can be checked out but the process is time consuming and labour intensive. I hope this answers your question but as Dirthog points out it is the same with many other excavators. Kind regards Uffex
As stated above, swing motion is stopped by dead heading the oil. Fine swing option allows leakage around dead headed oil for fine action. The actual swing brake only applies after all motion is stopped (usually 3~5 seconds), and also when machine is shutoff.
Thanks All. I will take some pics at the weekend and hopefully check it out a bit more. (I'm not using it everyday). I will post here again then.