Hello, we have problem with my sunward swe17s 2007 year. There is almost no power (very low pressure) for 3 operation: digging bucket, lifting boom and one side track. All others operation working fine. (These 3 operation relief valves are in the same side of the hydro block). We have already check all relief valves, filters, oil, oil pump pression. One more intresting thing what we found that if we make our drive stick in different position (you can see in photo) then everythink working fine. Anyone know where is the problem?
Good day Your machine is not so common, do you have any hydraulic schematics or manuals we can share to support you? Kind regards Uffex
Sadly but no, i cant find any scheme or manuals for that mini..
Good day Decleor I can try to help you it is going to be a little more difficult, your post indicates a issue with one section of the main valve . Can you take a photo of the main control valve, see if there is any label on the valve bank. Take a photo of the pumps and if you can indicate the lines, that will help. Kind regards Uffex
Here you go. But there is no label on valve bank
One more photo
Good day Can you get better detail on the pump, do you happen to have a parts book Kind regards Uffex
Good day Please see attached I have contacted Sunward unfortunately like many such outfits put after sales support low on their agenda. Kind regards Uffex
Hello, i got schematic
Good day DEcleor Very well done sorry for slow response I have been out of action for a few days, remarkable I text all the possibilties I could find did not even get a reply from any. Let me consume the diagarm and I wil make some suggestions. Kind regards Uffex
Hi again Declear Is there any possibilty you can get a copy in PDF format when I increase the size the lines become very difficult to follow. KR Uffex
Hello, yes i add manual in pdf
Good day Decleor I have taken a look at the schematic, the obvious e points I make as follows :- Three circuits are effected Boom-Bucket-One track, all of which are primarily supplied by pump No.1. You will note I marked those with red on the drawing. Pump one is dependent on a spool activating stopping passage of the fluid to tank for pump 1. This spool in turn is dependent on a solenoid valve becoming activated. The solenoid valve is commonly known as control lock out, which prevents the machine operating unless activated. As the remaining functions are working it comes down to that spool shifting at the MCV and the only possible obstruction is a small screen filter in the coupling to the valve spool, see Pp2 looks like a kind of triangle. Remove the filter and see if it is obstructed. If you are not so sure follow the small hose line from the control lock out solenoid. Kind regards Uffex
Hallo. I have the same problem with my sunward, and I am close to give up on it... Did you get it to work properly?
Good day The common component to the three circuits in the post is the relief valve, if you have arrived at an in pass I suggest you check what pressure you have by bottoming out the bucket cylinder. Kind regards Uffex
Hallo uffex Thank you for your good suggestion. I have not yet check the pump pressure, but i will do it soon. I believe its the wrong hydraulic diagram for my machine, so i attached what seems to be the right one. What I have tried is, to switch around P1 and P2 on the block. Made no difference. So made me believe the pump i working properly? I also tried to switch P1 relief valve with P2 relief valve. Made no difference. Changed olie and filter too. But it is a little strange, because it seems, when the machine is cold, all the hydraulic works fine, except for the one track motor, that is never really working(very slow). When it has been running like 10min, the controls starts to run slow and even stop at times. But then if i keep "pressure" on another function at the same time. It works okay..
Good day Thomas The schematic you post has a couple of unloading valves one for each pump, if one of these should be faulty it will allow the pump to dump to tank. Kind regards Uffex
Good day Thomas As you know support for some machines is poor, if you can take photo's of your work and post here on HEF I can make a report and file should another need help. The Schematic you posted would be nice in PDF format if you have it. Compliments on your trouble shooting. Kind regards Uffex
Hi Uffex. I will take a look and see if I can find the unloading valves.. I have a hard time reading and understanding the diagram. So again thanks for the suggestion, every idea is very much welcome! I get back with some photo's when i have time. I have attached the diagram in pdf format, the not the best quality but hope it works.. You are right, and it's for sure the last time i buy a chinese digger, there is not much help to be found.. Good day
Good day Thomas See the attached lines 15-16 from the main pump, if the schematic is correct there will be a "T" connection from each line to a common valve, it will have a line coupling to the tank also. If you can get a good picture of that valve we will try to identify the source and see what can go wrong.The machine is very similar to the Yanmar however the Yanmar has no valve like this one. If we can help some more come back. Good luck and Kind regards Uffex
Good day Thomas Attached is what I have been able to establish, I hope it is of help. Kind regards Uffex
Hallo again Uffex. Thank you for your help. I had a look at it the machine the other day and took a few photos. Pic 1: So.. From both pumps, there is a "T" fitting, like you said. One hose from each pump goes to this little hydraulic block (pic 1, red arrows). Here it seems the olie goes throw and out the other side (blue arrows). Then goes to the other block(pic 2).. Not sure if this is could be the dump valve?(pic1). There is 5 hoses attached to it, and I cant really get to follow the last hose ( Yellow arrow).. Does not seem to fit the schematic, but thats the only two blocks before the main block. Sorry about the photos quality, there is not space on the machine.. - Thomas