One day my bobcat decided to not swing in either direction. I had the swing pump rebuilt prior to this due to a leak. Mechanic said this was the issue and had it rebuilt again. Still won’t swing. Without the motor torqued in it will swing. Torque it, it won’t. A pressure test revealed 900 psi when it should be upwards of 2100. In not sure at what throttle this was tested. You can currently push the boom around by hand. They are telling me I should just get a new swing motor for $2k. Is there a relief valve in line that could be stuck open or something? Any ideas? Thanks for the help!
Do you have any flow into the motor at 900psi. Would think you would have some swing just lack of power. Was the motor tested after "rebuild" and was there anything done to the reduction side
There is flow. The place that did the rebuild said they had no way of bench testing. Nothing done to reduction side that I know. There is just no movement unless you loosen the motor. I don’t think it’s the motor unless they completely messed up the rebuild. Before the rebuild it just stopped. Not weaker.
Good day Most of these machine use the same pump to power the swing and blade providing that you have a blade, if the blade works good the issue is not with the pump. Kind regards Uffex
There is flow. The place that did the rebuild said they had no way of bench testing. Nothing done to reduction side that I know. There is just no movement unless you loosen the motor. But there is really The pump is fine. They are trying to tell me it’s the swing motor. I’m just not believing it. They don’t just stop.
Good day If the engine labours when the swing is operated that indicates that there is a fault with the transmission or the brake, normally there are relief valves which can lodge open and cause loss of swing. If the motor fails it will deposit stuff in the filters worth a check. Hope it helps you Kind regards Uffex
Thanks for the reply. Engine doesn’t labor. Nothing happens. You can push the boom around by hand. All filters have been changed.
If you can push the boom around by hand that indicates a transmission issue the brake should hold the machine even if the motor has failed. We do not have a parts illustration to give you, do you have parts or a manual ? Uffex
I do have a manual. The shop had a bobcat rep come and he said there is no brake on this machine. Just a pump that supplies everything and the swing-motor. Swing motor has two relieve valves on it that were not changed when motor was rebuilt. I’m thinking a bad relief valve or valves but I don’t know. I don’t understand how the motor would just stop. Even when it was leaking last year it worked fine. The shop that rebuilt it said everything inside looked fine.
On the main valve there should be a relief for just the swing section as well as a compensator, with it being both sides I’d bet it’s the compensator.