Which type of quick disconnect couplers to use?

[tomrscott]

I am getting a 2000 JD790 (delivered next week) and plan to add a Top and Tilt kit (probably the parts from CCM).

First my question, and then some explanation:
Q: What type and size of quick disconnects are standard for a CUT sized tractor for rear implement hydraulic lines? I've seen several types advertised at various hydraulics sources.

Now for some background that got me there:
I have decided to run a two spool, OC/PB joystick valve, mounted probably on the right side from the ROP, and then run the work lines from the valve down to four quick-disconnects mounted on a bracket above or on each side of the rocker arms.

The idea is that the top and side link cylinders can plug into these quick-disconnects, and then if I ever want to run hydraulics to a rear implement, I can disconnect one or both of the top / side cylinders and plug the implement in it's place. If I get the cylinders with the check valves, I shouldn't have to worry about them drifting.

Using a joystick style controller seems much more intuitive to me for the TNT than two handles. The front and back directions controlling the obvious top link adjustments, and the left and right control directions adjusting the tilt side link.

If anyone is interested in doing this on a JD790, I've done the research to know how to hook it up now and the 790 is kind of different from other tractors. I'd be happy to talk with others who've done this or would like to.

I've spent the last couple weeks reading everything I could find on hydraulics (background in electronic engineering and mechanical design, but not hydraulics). It has been quite interesting and very educational.

Cheers! /forums/images/graemlins/wink.gif

But I have one other question.

 

[ronjhall]

tomrscott
I would suggest that you put the same type and size that is on your FEL. This will require only one set of parts needed to make repairs.
When I put extra hydraulics on my tractor I used 1/4" quick disconnect couplers. But they have a different type of connector than my FEL. Now I have 2 different types for spares.

 

[kennyd]

I used the Pioneer couplers, they are the same as the FEL. TSC sells them.

 

[PineRidge]

I would tend to agree with KennyD, as Pioneer couplers are easy to get (TSC) and rather inexpensive.

While installing our front hydraulics on our New Holland we learned that the two standards used for quick couplers were: ISOA & ISOB. Our TC40D uses ISOA quick couplers on the connections for the loader and the NH selling price is about $39.00 a set. /forums/images/graemlins/blush.gif Since we were installing front hydraulics on a TN at the same time we also needed some ISOB couplers that the TN used and they happened to be much larger by the way. My mind says hey the TN couplers are larger in size so they are going to cost more money. NOT! The set of ISOB couplers were $18.00 a set.

My point is if you can replace a complete set of ISOA couplers with ISOB couplers that are interchangeable with Pioneer and other brands at half the price then why not save the money and make the conversion? I don't think your tractor or the hydraulics will be able to tell that you made the change and saved some bucks in the process.

 

[tomrscott]

So I guess the point becomes, which type is more likely to be used on a rental implement that I might want to connect to my 790? Could it be that the larger ISOB would be for larger implements intended for bigger tractors, and a smaller implement that would be reasonable to use on my 790 would be more likely to use ISOA? The cost difference might be a result of larger volume in the larger connectors. I would expect that the size would directly relate to hydraulic flow capacity. My 790's implement flow is limited to under 6gpm (steering is separate motor, gear tranny), but some big equipment has 10gpm to 25gpm and more. On the other hand, if the larger ISOB is more common on other implements, then that's the one to use.

At the end of the day, I appreciate saving a few bucks, but it is more important to have the hydr. connector that an accessory implement is going to have on it, maybe a rental implement. $20 or so is kind of lost in the noise compared to what we spend on these toys. /forums/images/graemlins/smirk.gif

 

[PineRidge]

As easy as the quick couplers are to change I vote the the ISOB less expensive ones for everyday use. This is exactly what we used for our front hydraulic circuit. Then if you want to keep a set around for dedicated use for some special rental implement pop them on at that time, your still money ahead IMHO.

 

[ronjhall]

A couple of months ago I replied to a post about someone wanting to purchase some Hydraulic Quick Couplers (could not find thread). His question was what model to purchase. The Pioneer type couplers have a ball for the check valve. Other versions of the couplers have a poppet valve like the attached picture. My FEL has this type. The ones I purchased from Northern Tool have the ball. They always leak when disconnected. I'm changing over to the poppet type that I found at a local supply house.
There is a third type that has a flat face and passes more flow.
None of the three type will work with the other.
All my couplers are 1/4". Depending on hydraulic flow quick couplers could be 1/4" to 1".

 

[Henro]

<font color="blue"> None of the three type will work with the other. </font>

I ordered the poppet type quick connects from that on-line supplier I have mentioned here in the past (That I will not use again), and they sent a mix of poppet and ball type halves.

Naturally, I did not like it, and the one time I was lucky enough to talk with the guy, he actually said both will work, that they are interchangeable, and that actually they come from parker mixed and they just throw them all in one bin and ship out in whatever ratio comes out of the bin when they are pulled to fill an order.

I said well, OK, but anyway I want them to all be the same. Send what I need to make it that way, and I will return the ones I don't need.

As some will remember, I got nothing more from that company and could never contact them again. After contacting the credit card company, I did get a refund for parts that vendor charged me for, but never sent (thankfully). But that is another story...

I took the guy at his word and although I did not like it, I used what was sent. And believe it or not, the poppet and ball ends don't seem to make any difference. I think it is because the seal is the responsibility of the O ring inside the female half, and not the ball or poppet, which just push open to allow hydraulic fluid flow.

I would not recommend doing this by choice though. I can't help but think that the poppet ends will eventually scratch the ball ends, resulting in leaks in the long term, when the halves are separated.

It never occurred to me that poppet and ball type ends would work together but they sure seem to, like the vendor told me. From what I can see anyway.

 

[tomrscott]

I checked out the Hydraulic Supply Company online catalog,

http://www.hydraulic-supply.com/pdf/488.pdf

which carries the Aeroquip line of hydraulic quick-connects.

This catalog also has some very interesting info. It seems that the ISO standards (both Series A and B) come in several "Size" dash numbers, -04 rated 1GPM, -06 rated 6gpm, -10 rated 12 gpm, -12 rated 28 gpm, and -14 rated 50 gpm.

The catalog has many different types and sizes, but they do list a series they call "Hydraulic Farm" FD72 and FD76 (their pages 517, 518). These also have a retaining ring groove on the barrel for bulkhead mounting, which seems useful. Interestingly these are only available in -10 size (hummm...), but on this series the -10 is listed as having 16gpm flow rate. The -10 size seems like plenty of capacity for most any CUT implement, so I am not surprised that's what they use.

The Hydraulic Farm connector part numbers are as follows:

FD72-1001-08-10 Female connector, 1/2-14 Female Pipe, valved, with ring groove on barrel for bullkhead mounting.

FD76-1002-08-10 Male connector, 1/2-14 female pipe, with Buna-N seal material and poppet valve.

Also worth pointing out that the Brass and Stainless couplings that are mechanically compatible are not rated for the kind of pressures we need, some as little as 1000 psi. A word to the wise, make sure the couplers you use are rated for enough pressure for your tractor's hydraulic system. The steel ones of the appropriate size seem to be 3000 psi or better and can handle bursts up to 12000 psi.

The other Aeroquip lines that are like connectors we might run across are:

The Aeroquip 5600 Series (page 500-502), which are compatible with ISO7241/1 Series A, and which look identical to the Hydraulic Farm series.

FD45 Series which they say is ISO 7241/1 Series B compatible (page 505-506)

FD89 Series which is the flush face style, compatible with ISO 16028, and meets HTMA (Hydraulic Tool Manufacturer Association?) requirements (page 513-514). The big advantage of the flat face connectors is that they lose less fluid, and introduce less air into the system when connected and disconnected, but in a system like a tractor, air flushes out pretty well, so that is probably not too big a deal.

I am kind of leaning toward the Farm series, which appears to be like an ISO A, but I think I will check with the local rental yard and see if they know what their implements use. I'll also look at my FEL, but that's not really a big factor, I can't see that I would ever want to connect the FEL to the rear hydraulics or a rear implement to the FEL hydraulics, so I don't see much advantage to keeping them compatible.

 

[ronjhall]

Henro
I guess I'll have to go out and check the different Quick Couplers to see if I have something different. /forums/images/graemlins/confused.gif
Have you checked to see if yours will fit the Quick Couplers on your FEL?
I can't check until later this morning. Everything is a sheet of ice from freezing rain. /forums/images/graemlins/frown.gif
Supposed to get in the 50's and clear up mess later today. /forums/images/graemlins/smile.gif