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Boom lift Drive Wheels torque fade
- Thread starter Ronray
- Start date
Thanks so much TVA! I actually bought that Brendan Casey Hydraulics book and it has a lot of symbols and explanations. And thanks for reminding me on that flow divider miss label. I'll be sure to mark that on my hard copy.
I think my next step is going to be to do with that manifold what I did with the hydraulic motors, just take them completely apart to see how they work LOL. And I will count the number of thread turns on the nuts and Allen's as I take them out.
Thanks again so much for your quick responses!
I think my next step is going to be to do with that manifold what I did with the hydraulic motors, just take them completely apart to see how they work LOL. And I will count the number of thread turns on the nuts and Allen's as I take them out.
Thanks again so much for your quick responses!
If that flow divider is a sool type ( most likely) look for scratches on spool or bore. Looks like they wanted to label it as proportional flow divider but forgot to put diagonal arrows across orifices!
Also look for plugged pilot passeges.
Also look for plugged pilot passeges.
Hello TVA. So I am taking the manifold apart and a couple of questions. Is this the counterbalance valve in the picture with the spring? Between the piston and the Allen screw was a darker looking oil almost like motor oil, unlike the red transmission fluid and the hydraulic lines and some debris like sand and rust, and I had to tap the Piston out with a screwdriver because it seemed to be a little jammed, and there looked like a little surface corrosion between the piston and the Allen screw on the cylinder wall. So Dremel tooled wire brush the inside of the cylinder and now I can move the piston with my finger up and down. It looks like the purpose of the Allen screw is 2 compress the spring, so would this adjustment be to allow more or less flow of hydraulic oil going to the hydraulic motor?
And my second question is since you recommended blowing out the manifold with compressed air, how important is it to remove the Allen screws like the one pictured with the Allen wrench and the other screw in plugs like the one pictured with the screwdriver pointing to it in order to blow out the manifold with compressed air? I ask this because please Allen screws and screw in plugs are really tight and may take an impactor to remove them.
And my third question is what is the purpose of the Allen screws in the manifold block? It seems like there is one Allen screw for every two large hoses entering the manifold. Are they bleeder screws?
And my second question is since you recommended blowing out the manifold with compressed air, how important is it to remove the Allen screws like the one pictured with the Allen wrench and the other screw in plugs like the one pictured with the screwdriver pointing to it in order to blow out the manifold with compressed air? I ask this because please Allen screws and screw in plugs are really tight and may take an impactor to remove them.
And my third question is what is the purpose of the Allen screws in the manifold block? It seems like there is one Allen screw for every two large hoses entering the manifold. Are they bleeder screws?
The tower looking things looks like the half of something like relief or counterbalance valve, the spring supposed to push the spool. Doesn’t look like it is cartridge, so spool is riding inside of the blocks body or there’s could be another sleeve pressed in to the body.
The Allen plugs probably diagnostic test ports, or technological opening if it has some components behind it.
Without exploded view or illustration some kind, or having it in my hands to do a “reverse engineering” it’s hard to say.
See if there’s a spool behind that large hex plug, if there’s a spool with smaller diameters at the ends and larger in the middle - that’s your flow divider.
Take everything apart, carefully photograph and document as you go, to correctly assemble it back together. Post more pictures - and we will try to figure it out together.
The Allen plugs probably diagnostic test ports, or technological opening if it has some components behind it.
Without exploded view or illustration some kind, or having it in my hands to do a “reverse engineering” it’s hard to say.
See if there’s a spool behind that large hex plug, if there’s a spool with smaller diameters at the ends and larger in the middle - that’s your flow divider.
Take everything apart, carefully photograph and document as you go, to correctly assemble it back together. Post more pictures - and we will try to figure it out together.
I would recommend to replace the O rings on the piston with Duro 90 ( for dynamic application) O-rings. Got to measure grove to select right size.
The oil behind the piston is a trapped oil that got behind the piston. That piston is just puts tension on the spring - so it’s not supposed to move unless springs tension gets adjusted!
The oil behind the piston is a trapped oil that got behind the piston. That piston is just puts tension on the spring - so it’s not supposed to move unless springs tension gets adjusted!
In the fourth picture to the right of the Allen wrench is the hole where the tower hex nut and spring came out of. Manifold case appears to be cast as one piece and does not split apart. So could the spool you are talking about be inside this one cast piece? And if so, how would I get it out to inspect?
So one end of the spring contacts the piston and the other end of the spring is contacting that area around the small hole in the manifold body. Should I be able to press that end towards the manifold body with a screwdriver? Is there another spring inside the manifold body around the spool? I Googled imaged hydraulic spool, but not seeing what I'm looking at.
So one end of the spring contacts the piston and the other end of the spring is contacting that area around the small hole in the manifold body. Should I be able to press that end towards the manifold body with a screwdriver? Is there another spring inside the manifold body around the spool? I Googled imaged hydraulic spool, but not seeing what I'm looking at.
There should not be another spring under counterbalance valve spool, spool should be two sections, one section should have three times smaller effective area. There should be another passage coming through manifolds body, beside big one connected to port ( hose ) hole.
You can use needle nose pliers to pull things out, or try to carefully blow compressed air to pop things out.
You can use needle nose pliers to pull things out, or try to carefully blow compressed air to pop things out.
Yes use impact, it’s probably hung up on aluminum washer or rubber O-ring pretty good. The only thing - before using impact put things back together or remove all loose components and put them aside, to prevent things flying out and loosing them or not knowing how they supposed to be.
Wow, I used the needle nose like you said to lift the spool out, and it just came right out! And now I also see that at the other end of the spool that there is a large screw but I was asking about using the impactor on. So I'm guessing that once I get that screw off there will be something else that will come out of that end?
Oh and also in the picture, you will see some large bits of metal shaving like perhaps from some other component in the hydraulic system that came apart and metal shavings got passed in the hydraulic lines to this manifold?. So that may have been blocking the spool from sliding in and out and thus restricting hydraulic fluid flow to that hydraulic motor on the right side?
Oh and also in the picture, you will see some large bits of metal shaving like perhaps from some other component in the hydraulic system that came apart and metal shavings got passed in the hydraulic lines to this manifold?. So that may have been blocking the spool from sliding in and out and thus restricting hydraulic fluid flow to that hydraulic motor on the right side?
Okay, here is a picture of a plunger looking type piece that came from the other end after I removed the screw. And guess what, more metal shaving bits. And those bits of metal are non-magnetic, so not steal, but maybe part of this aluminum manifold or perhaps a stainless steel part from elsewhere in the hydraulic system? I guess all the more reason to completely take apart this manifold and blow it out? But then, how could there be bits and pieces of aluminum from this manifold, since the only moving Parts would be the spools?
Firs t we need to clarify which spools we are talking about, counterbalance valves or flow divider. For that you need to be 100 sure what is what, I’m not, because I’m not there to look at the components and identify them.
If you will remove flow divider completely then you will have situation as working wheel differential - the wheel which has less pressure will get more flow!
If you will remove flow divider completely then you will have situation as working wheel differential - the wheel which has less pressure will get more flow!