Hydraulic Top link

[MtnViewRanch]

Thanks for the info Brian I will keep you in mind if i decide to get one. I think my oem top link measures just a hair over 18". Would I be able to get a htl that shortens to 18"?

Our HTL that has an 8" stroke has a 17"- 25" working length. Do you use your top link shortened up all the way? It is rare when a hydraulic link has the same working length as the manually adjusted links.

 

[Glen Watkins]

I tighten the tl just to hang the mower over a steep bank edge but a 19" would probably be fine. I will check it out this weekend and see how 19" looks.

 

[KennedyDiesel]

Spoke with Surplus Center and then the mfr. Mine will be replaced under warranty. I have ordered teh new one and as soon as it is installed I'll send the old one in.

The 17" short length sounds intriguing. I'm at 18.5" right now. I forget which way I was wishing, but I think shorter.

I don't see double piloted check valves on the Fit Rite. My checking has ceased to work and let me tell you a drifting top link sucks...

 

[MtnViewRanch]

Spoke with Surplus Center and then the mfr. Mine will be replaced under warranty. I have ordered teh new one and as soon as it is installed I'll send the old one in.

The 17" short length sounds intriguing. I'm at 18.5" right now. I forget which way I was wishing, but I think shorter.

I don't see double piloted check valves on the Fit Rite. My checking has ceased to work and let me tell you a drifting top link sucks...

You know that if you changed the seals in your control valve, that you would not even know that the top link DPOCV is faulty, but then that is the main purpose of the check valve, to compensate for a leaky control valve.

You're right, no DPOCV on our Cylinders and a drifting cylinder is no fun to deal with. I have found that there are enough reasons not to have the check valve that IMO they out weigh the reason to have the check valve. ( the main reason for the check valve is to compensate for a leaky control valve and that leaky control valve is why a person has hydraulic cylinder drift) If a person has a good valve with good seals, the drifting is so minimal that there is no good reason to have the check valve IMO.

Others wholeheartedly disagree with me and are convinced that the cylinders with the DPOCV are the only way to go, and that is fine. What I know is that the OEM top and tilt cylinders from John Deere and from Kubota do not have any DPOCVs on them. All the industrial graders that I have ever seen never had any DPOCVs on their cylinders. What all of this leads me to believe is that they are not really needed and when there is a drifting problem that the seals on the control valve need to be replaced. And those seals might if you look real hard, cost you all of a dollar, normally they would be less than that.

Let me know if you want a 17"-25" working length top link, I have a used one that I can let go cheap.

 

[KennedyDiesel]

We don't have super precision valves in our relatively economical tractors. The loader buckets drift etc and there is no good way to solve this. It's not that something is worn it's that it's good enough for it's intended purpose.

I prefer a rigid top link when using ground engaging equipment. The only way to come even close to this is with check valves OR a lock off valve.

 

[MtnViewRanch]

Yes I know that most of our tractors that most of us have here on TBN have economical spool valves. There are many of us that have little if any drift with our non DPOCV cylinders.

I have little to no drift with my Mahindra tractors, and many others here on TBN with there different brands and models are the same way. And if it is actually such a problem, then why don't John Deere and Kubota have them on their top and tilt cylinders? These are the same tractors with the same valves that people here on TBN have.

I'm not saying that the problem doesn't exist, just that when it does become a problem it can be an inexpensive fix. I just changed the seals in my aftermarket valve that I had purchased from SC. That valve was not even 3 years old.

Again, many people prefer to have that rock solid will never move even 1/8" cylinder and they do not care about the benefits of being able to use float mode with their cylinders. For those people the cylinders with the DPOCVs are clearly the way to go.

Hopefully sometime in the future I will be able to offer the check valve as an option and I will then be able to make even more people happy.

 

[KennedyDiesel]

Upon further review, it seems that my top link does hold quite well... in certain situations. Like standing still. I can pull it all teh way in and it will hold my Harley rake up seemingly indefinitely. It's when I start to move that it drifts. My guess is that the bouncing action of movement is bypassing the valves somehow.

So I'll see how the replacement unit wors, but it looks like I may need to devise a mechanical lock off for the fluid. Something like a needle valve that instals in place of a banjo bolt would be really cool. That or maybe I could add a small restrictor in the lines to dampen pressure spikes...

 

[kevinwak]

Upon further review, it seems that my top link does hold quite well... in certain situations. Like standing still. I can pull it all teh way in and it will hold my Harley rake up seemingly indefinitely. It's when I start to move that it drifts. My guess is that the bouncing action of movement is bypassing the valves somehow.

So I'll see how the replacement unit wors, but it looks like I may need to devise a mechanical lock off for the fluid. Something like a needle valve that instals in place of a banjo bolt would be really cool. That or maybe I could add a small restrictor in the lines to dampen pressure spikes...

You might have to rebuild your control valve as Brian suggests. If your valve isn't rebuild able you may have to upgrade to a better quality valve?

 

[HayDR]

The Surplus Center DPCV unit and our unit is exactly the same. I have been using this Italian manufacturer since 1998. The DPCV is designed to work on that cylinder. It can be adapted to other cylinders but it does not mount up as nice. BSPP is the standard in Europe. In Europe, many applications use Banjo fittings and these Banjo fittings are cheap in Europe. In the AG industry Banjo's are not as common on USA manufactured implements and are expensive on this side of the pond.

All of our top links and side links have the DPCV. I have someone calling me everyday or 2 asking me for a DPCV for their cylinder. Our hydraulic top link & side link cylinders are priced competitive with other non-DPCV units.
Mark Carter

 

[greg_g]

There are many of us that have little if any drift with our non DPOCV cylinders.

I'm in that group, and view the check valve HTLs as little more than an expensive bandaid for an otherwise ailing hydraulic circuit. For the naysayers, I'm basing this on having swapped two HTLs of different manufacturer among several different tractors also of different manufacture. The only thing in common was a good cylinder connected to a well-maintained hydraulic system. Another vote against them would come from those who use the "float" capability on tractors so equipped. A DOPCV would effectively cancel any float capability extended to that cylinder.

Understand however, I have nothing against the retailers who stock them. If there's a market, there should be someone to provide for it. Hopefully they stock both kinds of HTLs though; one for the bandaid crowd, and one for the mechanically conscientious.

//greg//