Hey guys new to the forum. Have helped alot so far. I tried searching but could not find. If this is a repeat I apologize. I bought a 580 super e recently and slowly been fixing odds and ends on it. I have not done much digging with it because most of the cylinders have been leaking like fountains. I got the parts and rebuilt the two boom and the dipper cylinder. I've noticed now that if your raising the boom and try to move the dipper it stops going up when the dipper moves. Is this normal? Thanks for the help
I believe that is normal on loader backhoes. I don't ever recall running one of that vintage of any brand that didn't do that.
I have found if you don't give it full throttle when moving two levers both functions will work. Precision and getting a feel for the machine is what works.
Thanks John c. This the first 3 stick machine I've ever messed with so it's very possible it's the operator
And thanks spud monkey, did realize I had 2 replies ♂️
You do need to (as we say feather the controls) as you operate the machine and find the sweet spot where they will work together at the same time. You also need to check the load check valve o-rings by bottoming out one function and seeing if another function tries to move. This will cause loss of function and power.
Thanks coy. The feathering I was doing but not sure about the other. Will have to try that.
This may be a dumb question but what dose the load check valve do? Just so I can try and get an understanding of how it works.
Also you may need to check your main and secondary relief pressures.
The load check holds pressure in the function ie boom, dipper etc… that way when you operate a lever it is ready to work and you don’t have to wait for it to build press.
That makes sense. Thank you for the explanation
To add to the explanation, an open center hydraulic system with a positive displacement pump essentially has only tank pressure and line resistance to flow when a spool valve is centered. If the boom were in the air when the spool is moved to raise the boom higher, it would drop some until the pressure on the supply side of the spool matched the pressure on the boom side. To prevent this a check valve is plumbed in between the spool and the boom. Now the pressure on the pump side has to exceed the pressure holding the check valve closed before the it opens and allows the oil to flow to the boom cylinder. The cap or plug for the check valve is usually in between the tubes or hoses for each circuit that connect to the main control valve.
Wow, I sure do got alot to learn. Thanks fir going indepth