Hi all, just got my kama TS354 from chip today. so far I am impressed but , I have a question/issue with the chinese hoe. all seems to work well except for 1 thing. I can crack the valve to swing the boom right and all goes as expected, nice smooth travel. However, when i crack the valve to swing left I can hear the high pressure bypass kick in and the engine pull down. If I go vavle full open it goes on and moves without pulling the engine or activateing the pressure bypass. Is this normal or do I have an issue?
Backhoe LW-6 Backhoe
- Thread starter DwayneB
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SPIKER
Elite Member
that does not sound good, alsmot sounds like the valve cracked open causes the valve spools to close off the flow from the pump befor it opens the flow to go to the cylinder... this would indicate a machined part which was not done correctly. only way to tell this is to pull the effected spool and one next to it for compareson... remember that an inch op on the end of the valve handle is very little travel down on the hyd spool. SO a small deviation of less than 20 thousands could make a big differance. one thing is that you could swap spools from the outrigger to the effected spool for the swing valve... not sure if these are SAME or not, but would think so for parts stocking china side...
other thing to check to make sure nothing is stuck in the hyd lines and or in the valve body/spool ports. small hunk of debris could cause some problems but I would thing that moving the spool slow would be OK in the case of junk in there and moving it fast would cause the blockage to push/suck up aginst the passage stopping the movement,
if these are still the same style valves there is no o-rings in there just very tight tolerances so only very small amount of oil ccan/could leak by past the spools... so shouldn't be an o-ring type issue
You can also check to make sure that the lnikages are all tight and no pins are bent or missplaced... Pretty straight forward hunk of mechanical art in those valves so there is very little complication to worry about. don't take the relife valve appart unless you have gauges to put it back together with. otherwise re-setting the relife pressure is a pain.
hope that helps
mark m
other thing to check to make sure nothing is stuck in the hyd lines and or in the valve body/spool ports. small hunk of debris could cause some problems but I would thing that moving the spool slow would be OK in the case of junk in there and moving it fast would cause the blockage to push/suck up aginst the passage stopping the movement,
if these are still the same style valves there is no o-rings in there just very tight tolerances so only very small amount of oil ccan/could leak by past the spools... so shouldn't be an o-ring type issue
You can also check to make sure that the lnikages are all tight and no pins are bent or missplaced... Pretty straight forward hunk of mechanical art in those valves so there is very little complication to worry about. don't take the relife valve appart unless you have gauges to put it back together with. otherwise re-setting the relife pressure is a pain.
hope that helps
mark m
Thanks, it didn't sound good to me either. My farm is 50 miles from where I live so I only get up there on weekends. I hope to take a good hard look at it this weekend. I hope its as simple as swaping spools. Chip is still on the road, but I am sure he will help me when he gets back.
Best as I can tell from the diagram is the spools are different for the out riggers, 2 port vs 4 port. On the bright side the spool in question is on the end. Hopefully is just a peice of junk in the valve. Thanks again for the help. I am a hydraulics virgin.
JohnS
Platinum Member
I am assuming the LW is the same as the JW on how the swing cylinders work. JW Hoe
The swing cylinders are plumbed only to one side. One cylinder has to extend to make the other retract. Also to retract, the valve on the one being pushed, has to be open to allow the oil out. It sounds like when you try to slowly move to the left, the valve is opening on the cylinder to do the pushing, but the one being pushed hasn't opened yet. When you move the lever quickly, it works because the valve to release the oil, did open.
I haven't worked on those valves enough to know if there is any adjustment, and if there is, how delicate it is. One valve is above the other, and activated by the same arm. Both need to open at the same time, or the one that is being pushed open slightly before the one doing the pushing. Getting it to work properly in both directions, may be a compromise.
I hope all this pushing and pulling hasn't confused you! /forums/images/graemlins/confused.gif
The swing cylinders are plumbed only to one side. One cylinder has to extend to make the other retract. Also to retract, the valve on the one being pushed, has to be open to allow the oil out. It sounds like when you try to slowly move to the left, the valve is opening on the cylinder to do the pushing, but the one being pushed hasn't opened yet. When you move the lever quickly, it works because the valve to release the oil, did open.
I haven't worked on those valves enough to know if there is any adjustment, and if there is, how delicate it is. One valve is above the other, and activated by the same arm. Both need to open at the same time, or the one that is being pushed open slightly before the one doing the pushing. Getting it to work properly in both directions, may be a compromise.
I hope all this pushing and pulling hasn't confused you! /forums/images/graemlins/confused.gif
Stimw
Elite Member
How do you like the Hoe? I just bought a YW-6 that I am going to mount on my 3510 Branson. I just have to re-make the sub frame and hook up the hydralics. It looks well made.
