hi my 440b has a leak at the control valve piston . I have never had this apart , it has two allen head bolts on what appears to be a cover. if i pull this off is there o rings for seals ? do i need special seals. i do not have a manual for this machine.. thanks paul
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thanks just a few more questions, the control valve is still in the bobcat and the piston or spool? is connected to a rod going to the foot petals, i can unhook the rod take off the cap, pull out the spool and replace the o rings .. will anything else fall out of this... sorry for all the questions as i have never delt with a control valve and the way it works... again thanks,, i need to replace as it leaks oil as it sits...
Depending on what section it is, there may be steel detent balls. These will be behind the alloy cap at the back, if you are careful you can remove it without pulling the cap off. With it all out, when you pull the spool out, nothing will fall out. It's essentially just a rod with grooves cut in it that match ones inside the valve block.
It's best to drain all the oil you can before starting too. If not, it will make a bit of a mess.
SkidRoe
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You should not have to worry about detents with a 440B - they are very basic. Also, draining the reservoir is not absolutely necessary, as it is below the level of the control block. You will need to remove the control block from the machine to do the job. It is a bit of a fiddly job to remove the block, but it is not too bad. Depending on the age of your machine, it may use quad rings or v-rings. If you put your e-mail address in your profile, I can send you some documentation that should help.
I didn't think about the location of the oil tank... Thanks for the correction.
drivehard
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I have just about the same thing going I think. This is my first time really working on one so we shall see how this goes. There are three of these covers with allen head bolts on the back. Mine is shooting fluid out of the cover like this that is in the middle. It also has the two allen head bolts but is shooting oil out of the pin hole in the back of the cover. I dont even know if that one is a valve or just what it is. Will I have to remove the entire thing as well? Any insite would be awesome.
SkidRoe
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I am assuming that you are also working on a 440b. If so, that would be the control section for the boom lift.
And you will need to pull the control block out. There is just not enough room to do this job properly when it is in the machine.
Once you have it on the bench and start tearing into it, ou will be glad you pulled it out. Best of luck!!
Coltjansen
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I'm having the same problem is there any way you could send documentation to me also [email protected]
[email protected] i could use those docs as well if you will share, that's where im at right now,,, hands tooooo big to get to the allen screws looks like i have to pull the control valve....... help Mahalo
