I’ve just picked up a Yanmar vio 27-5 and it will swing left for a few minutes after sitting over night but not once it starts to warm up. It swing right correctly but doesn’t seem to brake in that direction almost like the pressure from left swing is maybe bleeding to the right causing the brake function to not work. Everything else on the machine functions properly. Anyone have any ideas or advice before I head to the dealer?
Good day Plug lines "A" & "B" with a gauge see if the issue is in the motor or source. Kind regards Uffex
I will have to go pick up a gauge. Any chance you know what size fitting those are so I can grab whatever adapters I need?
Good day Real sorry I will try to find but nothing on hand. Kind regards Uffex
Went and picked up a gauge set from a friend but none of the fittings/adapters are right so I suppose I’ll try to find the right ones tomorrow.
Is it ok to attached the gauges so that the lines just “deadhead” into them or will I need to tee into them?
Good day Dead end the lines from the main valve block measure each full lever movement. Kind regards Uffex
Won’t swing to the left but I’m getting 2900psi at idle and 3400psi wot Right swing is 2700psi at idle and 3300psi wot I assume this means the pump and control valve are good? That mean the swing motor is bad?
Won’t swing to the left but I’m getting 2900psi at idle and 3400psi wot Right swing is 2700psi at idle and 3300psi wot I assume this means the pump and control valve are good? That mean the swing motor is bad?
I’ve let it run for a while now and it has changed. Now it’s 2400psi swinging left at idle and 1950psi at idle swinging right. 2950psi left and 3350psi right at wot
Meant 2950 right and 3350 left wot
Good day JL One side appears a little low but it confirms the source is good and the issue is at the motor. I suggest feel and listen if you can detect movement from the motor remove the motor to the bench inspect the splines have not sheared. Post photos so we have a good idea what is going on. Kind regards Uffex
Well, good news and bad news. I switched the supply lines to the swing motor which should have reversed the problem if it was in the valve block or controls. It didn’t which would suggest that the issue was further down the line. I went out this afternoon and removed the 6 swing motor mount bolt but the motor wouldn’t lift so I hooked a strap around it from the roll cage and put pressure against it. It still wouldn’t budge so I cranked the machine to rock the swing function back and forth to “shake it loose” and the swing function was back to normal. I assume something was hung up in the motor and all the rattling I did with the impact gun (went through four 6amp battery on Milwaukee 1/2” gun) getting the mount bolts loose must have gotten things back right. I made the purchase for $12k so I think I did well.
Good day JL It is good news that the machine is Okay at the moment, I would be concerned that the root cause has not been established. Kind regards Uffex
Yea, that’s why I said good news and bad news. I hate not knowing and having the thought of it happening again looming over my head. I’ve never broken into a swing motor before so I’m making assumptions about the inner workings. Either way, I think it’s safe to say the issue is/was in the motor and they aren’t terribly expensive from what I’ve seen. Thanks for all your input and if/when the issue pops up again, I’ll report back.
Well, we got about 10hrs of work out of the machine and the problem came back but only this time, it was reverse what it was before. Now it won’t swing to the right and has know swing brake to the left. Both left and right supply pressure are still the same as before. Do you by chance have a schematic for the swing motor? I am having trouble thinking of what could cause this issue and go away then come back only opposite. Any thoughts?
Well I just went out and pulled the swing motor relief valves, disassembled and reinstalled but the problem remained. I also switched the sides and the problem didn’t switch. However, I moved the joystick side to side rapidly at idle and the problem went away but came back. I ran the throttle to wide open and moved the joystick rapidly and the problem went away and has yet to come back. Does that tell you anything?
Good day JL I am short with the schematic however if you can post a photo of the motor and label I may be able to identify the make and provide bettter information. Kind regards Uffex
heres a link to it with better pics. The mounting bolt pattern is different on this one though. Kayaba Hydraulic Motor MSG-27P Free Technical Support, Competitive Price, We are supplying Kayaba Hydraulic Motor MSG-27P, Welcome to contact us! sunoreparts.com
Good day JL Attached some information of what to look for. KInd regards Uffex
Thanks! I will dig a bit deeper. I’ve got a very busy week but will report back with what I find. Thanks again.
Hi did you solved it have same problem?