Hydraulic top link issues

[Kodiak45]

Just so we are clear and everyone is on the same page. ----There are only 2 ports on the cylinder.
-the fluid flows both in and out of these ports.
-The way to control the inflow or exhaust is by turning the desired restrictor device around as the opposing flow is not controlled.

So there will be a flow control device on both ports, it's just a matter of whether the flow going in the cylinder is controlled or the flow going out and the best method is controlling the outflow/exhaust.
Is this accurate?
The more I think about it, the more it makes sense. Nothing is as simple as it seems.

 

[LD1]

Just so we are clear and everyone is on the same page. ----There are only 2 ports on the cylinder.
-the fluid flows both in and out of these ports.
-The way to control the inflow or exhaust is by turning the desired restrictor device around as the opposing flow is not controlled.

So there will be a flow control device on both ports, it's just a matter of whether the flow going in the cylinder is controlled or the flow going out and the best method is controlling the outflow/exhaust.
Is this accurate?
The more I think about it, the more it makes sense. Nothing is as simple as it seems.

Yes its typical that the exhaust is what gets metered for speed control.

I the scenerio as it relates to the toplink, FULL FLOW going into the cylinder to extend is STILL not enough to keep up with what is leaving. Thus the issue people are experiencing in this thread.

Need to make that flow leaving, leave SLOWER, so the fluid coming in has time to fill the cylinder and not draw a vacuum/suck air.

 

[Fallon]

Does anyone know how much vacuum (negative pressure) is needed to cavitate hydraulic fluid?

Atmospheric pressure is just under 15psi. So it's a pretty safe assumption it's somewhere under -15psi.

 

[Luke'sScreenName]

Atmospheric pressure is just under 15psi. So it's a pretty safe assumption it's somewhere under -15psi.

Thanks.

 

[Kodiak45]

 

[Kodiak45]

We are rock solid now. Thanks for all your help

 

[ovrszd]

We are rock solid now. Thanks for all your help

Glad it worked for you!!!! And these are adjustable valves??

No criticism here, just an observation. You may want to put a longer hose on the barrel end. The prying pressure of that hose trying to straighten is being applied to your quick coupler joint. Might see an eventual failure or leakage.

 

[Kodiak45]

Glad it worked for you!!!! And these are adjustable valves??

No criticism here, just an observation. You may want to put a longer hose on the barrel end. The prying pressure of that hose trying to straighten is being applied to your quick coupler joint. Might see an eventual failure or leakage.

yes they are adjustable. I'm glad you think that hose needs to be longer. I was thinking the same thing. That's the next to do for next week, but today I'm going to enjoy the box blade and the hydraulic top link.

 

[ovrszd]

yes they are adjustable. I'm glad you think that hose needs to be longer. I was thinking the same thing. That's the next to do for next week, but today I'm going to enjoy the box blade and the hydraulic top link.

Yep, I would too. You deserve some quality tractor time!!!

 

[LD1]

Money well spend IMO.

There was never anything mechanically wrong with your system. Just a flow problem. Good work and I think you will like the adjustable valves.

 

[Luke'sScreenName]

I also need some similar help with a chattering top link. OP, if you feel like this hijack is disruptive please let me know and I will start a new thread. :drink:

I bought a new cheap hydraulic top link last fall to replace an old leaking one I had. On extension, only under load, it chatters badly. It's worse at faster speeds but present even when feathering the valve. It's quite loud and vibrates the whole tractor. I don't think this is what is but it "feels" like I imagine dry/sticking seals would feel. I could use some help from those with more experience. This a link to the you tube video (careful, it is loud). Thanks in advance.

 

[LD1]

I also need some similar help with a chattering top link. OP, if you feel like this hijack is disruptive please let me know and I will start a new thread. :drink:

I bought a new cheap hydraulic top link last fall to replace an old leaking one I had. On extension, only under load, it chatters badly. It's worse at faster speeds but present even when feathering the valve. It's quite loud and vibrates the whole tractor. I don't think this is what is but it "feels" like I imagine dry/sticking seals would feel. I could use some help from those with more experience. This a link to the you tube video (careful, it is loud). Thanks in advance.

How much load was that? Didnt look like much.

IMO, I think that is way too fast.

 

[Luke'sScreenName]

About 800lbs about 1.5ft back

 

[Luke'sScreenName]

I was really hoping y'all had some educated guesses....

 

[ovrszd]

I was really hoping y'all had some educated guesses....

I thought maybe LD1 had some ideas. I believe it's a cylinder issue since you didn't have the problem with the other cylinder. Things like that would aggravate me. Sorry I don't have any suggestions...... Curious about the resolution though,,, if you find one....

 

[ovrszd]

...back to your top link. What size rubber hoses are going to this? Yours is moving 4 times faster than mine but I have the needle valve on mine.

That's how fast mine used to move until I restricted it to stop a vacuum problem. I loved it. Had to learn over again with it slowed down. I especially liked it when carrying my 10ft 3pt brushcutter. Moving CRP I never lifted the 3pt, just used the top link. Especially handy if you hit a rock or some obstruction, quickly got the cutter over the problem.

 

[Luke'sScreenName]

Ya, I'm going to have problems if slowing it down is required.

 

[LD1]

My suggestion was that its moving too fast.

What size cylinder bore and rod was the old one?

 

[Luke'sScreenName]

The same or slightly smaller...
Might just have to rebuild the old cylinder... :confused3:

 

[LD1]

What was wrong with the old cylinder?