# Hydraulic fill port, dump adapter for LS tractors



## MTCulper (8 mo ago)

LS MT357 HST here (with cab).

2 questions:
1. Is my tractor open or closed center hydraulic system?
2. Dump adapter for hydraulic fill port?

1st, until I got this Work Saver Post Pounder (type that raises hydraulically and uses gravity to hit the post), I did NOT know about open vs. closed center hydraulic systems. I'm pretty sure now, that what I got is a pounder setup for closed. When it is hooked up correctly (push side of remote"), it acts like it is dead-heading at the control valve on the pounder. Anyway... kinda annoying that no one at my local dealership could help. They had no idea what I was talking about and tractor manual doesn't reference closed vs open either. Wasn't until I got frustrated, called the WorkSaver tech support. They claim that nearly all new tractors are open center. Sound right?

2nd question: Adapter for the fill port on the tranny so I can hook up the large free-flowing dump hose to it? Does this exist? LS thing likely or generic? People just make their own? The dump hose coming off the attachment is 3/4" with an NPT male end. I kinda made one over the weekend. Just bought a barbed 3/4 adapter and a little 4" piece of 3/4 poly pipe. The poly pipe slips in (barely/tight) to the fill port on the tractor tranny.

This as good as anything i'm going to buy? Also, another item my dealership knows nothing about. They've never heard of hooking up a "dump hose" to the fill port.


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## BigT (Sep 15, 2014)

Howdy MTCulper, welcome to the tractor forum.

Your tractor's hydraulics are open center. Most tractors are open center. See attached data sheet for your tractor. Look under the hydraulics section.



https://www.tractordata.com/farm-tractors/010/6/2/10624-ls-mt357.html



Many guys use the hydraulic filler port for their return line. You can make your own... if you can find the correct size and thread "pipe tee". Screw one end of a pipe tee into the filler port. Your return line goes into the side of the tee. The filler cap goes into the top end of the tee.


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## MTCulper (8 mo ago)

BigT said:


> Howdy MTCulper, welcome to the tractor forum.
> 
> Your tractor's hydraulics are open center. Most tractors are open center. See attached data sheet for your tractor. Look under the hydraulics section.
> 
> ...


Thanks! Surprises me that LS doesn't have this in their own literature. But, everything i've learned this weekend about open vs closed center hydraulics, this all is making sense and solidifying the fact that my system is open. I also have 3 remotes. 2 detent, and one standard. If I had a closed system, I would not think they'd be giving me the 2 detents. Also, just the way the loader behaves. It builds pressure slowly and I notice this while back-dragging with the bucket especially. It builds pressure faster when I have higher RPMs. All making sense now.


Ok, so we're saying get a tee. Unthread the plug on the housing which holds the rubber stopper / fill-dipstick. Assuming I can get the same height (so that the dipstick continues to read correctly), I could have one end of the tee hold the dipstick and the other end be the threaded 3/4 connection. Heck, could even put a little ball valve on it I suppose for the dump end. I like it. Nicer than way I rigged up this weekend!


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## MTCulper (8 mo ago)

BigT said:


> Your tractor's hydraulics are open center. Most tractors are open center. See attached data sheet for your tractor.


My local dealer finally got someone with hydraulic experience who swears on his career this is incorrect, and that the data sheet you posted from tractordata is incorrect. He states that ALL new LS tractors in the last few years are closed-center and they simply do not fit any of them with open centers anymore. The manual does NOT specify and i'm not savvy enough to tell by looking at how it is plumbed.


Still stuck 6 months later trying to get a post pounder to work with my new tractor. In fact, any SA (single acting) device which has a dump hose simply will not work. I've tried with both an open-center valve (on the pounder) and a closed center. i've tried both of my detent remotes, in both positions (forward and back), hooked to both sides of the remote (again with detent forward and back). Literally, ALL possible combinations do not work. The tractor acts like it's under load, but nothing happens at the hydraulic output. I can tell by putting my hand around the hose, no pressure is going to the hose.


I was told by another person that regardless of whether my tractor is open or closed center, all newer tractors have some sort of safety device built in that will NOT allow you to hook up to only one side of the remote. And now the dealer wants to put in a T in and bypass the remote in such a way that you hook up to both sides of the remote with the supply line, and still dump the return line to reservoir. Of course the charge to make this work is going to be spendy including another trip to the dealer an hour away.


Beyond frustrated at this point. Kinda thinking I just give up on ever running a post-pounder behind my tractor and buy a skid steer with a high-flow pounder or buy an old tractor to do nothing but run the pounder.


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## Fedup (Feb 25, 2014)

No offense, but I think your local dealer STILL doesn't have anyone with hydraulic experience. Closed center hydraulics on a tractor under 100HP would be a rare bird indeed. I won't say it can't happen, but it would be most uncommon. 

That said, I don't know the LS brand, but a tractor is a tractor. There can't be that much different about your system than any other similar brand/model. I have little doubt it's open center, and I can't imagine why you can't use a remote valve to supply oil to an implement without getting complicated in order to use just one of the couplers, and return the exhaust oil back into the tractor case by the most convenient means possible. If you can't do that, you bought the wrong tractor. 

I've heard and read that New Holland (a brand I'm much more familiar with) now markets certain models that are actually LS manufactured. I can't confirm or deny that. Other than possibly one of those, I don't see many LS units out there locally and have little to draw from, so I'd be curious to see some photos of the pumps, valves, couplers. etc of your model.


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## MTCulper (8 mo ago)

You might be 100% right on the dealer. All I know is he has more experience than me with hydraulics which isn't saying much.


It's nearly identical to a NH Holland Boomer (T4B) with similar frame size and HP. I think the biggest difference is my MT3 has a Mitsubishi engine where as the Boomers have LS Mtron engines. Kinda funny irony there. The cabs are tough to tell the difference and I think made by the same company (Mercedes so I'm told). They are REALLY similar tractors from what i'm told.


I could take some pictures, but i'm not sure exactly what to even look for given my lack of experience. If you think you can help, maybe we assume you're right about an open center and just start with pictures of the basics? Here is the only semi-helpful page in the manual on the remotes - cause RTFM Iguess. I find the wording here conflicting / confusing:




















A bit dirty. Just got done bailing for the season:









Here is the valve on the post pounder + hose connections. One on the far right dropping out of the valve at a 90, is the dump hose. Hose on left (as well as connection end i'm holding up) is the supply hose. One out top goes to single acting cylinder which so far won't do anything at all in the slightest. There is a handle that works this valve from neutral to acting to dump (3 positions) on the other side of the valve pictured:










Finally... here is the best picture I could get of the valve(s) that all of the remote handles go into. Might be able to get better pictures tomorrow in daylight, but things are pretty compact under there:


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## Fedup (Feb 25, 2014)

So far it all looks as I would expect, no surprises yet. Some photos of the pumps would make the case. I would expect they are engine mounted and driven, as is the norm these days. Simple open center gear pumps I suspect.


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## MTCulper (8 mo ago)

Update...

I actually reached out to corporate a few days ago and simply asked: "Is the MT357 open or closed center hydraulic system" to which the response was " this tractor is an open center system."


I switched the pounder back to an open center valve config (just changed out a plug on the pounder). Wanted to get you a video of how it behaves. In one detent position the tractor acts as if it's under load and nothing happens. In the other, this occurs:

LS MT3 series tractor. Cannot get remote to work with SA (single acting) cylinder - YouTube 

Notice how on one side of the remote, it's acting as if it tries to pull (not push) fluid. See the hose flexing in. On the other side it literally does nothing but acts as if the tractor is being worked / will die.
Starting to think that old farmer was correct: There is some safety device installed on these machines which will NOT allow fluid to leave the system unless it is being received back on the other side of the remote. ie. this will never work with the stock remotes.

Also, I tried the non-detent remote with the wife holding the lever both forward/backward. Exact same behavior.


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## MTCulper (8 mo ago)

On advice of an out-of-state dealer (figured I'd just try another one), said to check the quick couplers. Though they are brand new, he claims: "I have seen it 100 times at least that a brand new quick coupler will not allow fluid to pass through, try another end/take hose off, valid fluid will go through it." He also claims "there is no way in hell a company like LS puts a safety device on that only allows flow one way."

Since i've tried all 6 quick couplers on the female (tractor) side, I assume it could only be the male end that is brand new on the implement. Will check it out after work.


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## Fedup (Feb 25, 2014)

I know for a fact I've never seen an open center hydraulic configured as you say this one is. But then I haven't seen everything yet. 

Simple test for you. Take the hose that supplies your implement, remove it from that implement, but leave the nose connected to the tractor coupler. Put the open end into a bucket. Start the tractor and try the valve again. See if it sucks air or flows oil.


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## MTCulper (8 mo ago)

Fedup said:


> I know for a fact I've never seen an open center hydraulic configured as you say this one is. But then I haven't seen everything yet.
> 
> Simple test for you. Take the hose that supplies your implement, remove it from that implement, but leave the nose connected to the tractor coupler. Put the open end into a bucket. Start the tractor and try the valve again. See if it sucks air or flows oil.


Ultimately this suggestion led me to the solution! 


No, it did not flow. Er... not very much. Wiggled quick disconnect coupler / pushed it in/out and get flow. Since it's acting like this on all remotes, I'm going to say this is the fault of a bad pioneer 8010-4 1/2" coupler (not the couplers on the tractor side). The coupler is brand new from Tractor Supply. I had to change it when i bought the implement because the previous owner was using it with a skid that has a different style connector. Something wascausing it to not seat 100% right. My dealer claims he has seen this more times than he can count - interesting. Threw the old one out, new coupler and good to go.


Silver lining: 
I understand the hydraulics on the tractor a lot better for future. Glad this all works and it wasn't some weird safety thing that someone else had claimed might be the issue. I also good good support from a FB page for LS tractors. Helped that one other person on a similar model said he'd hooked up a SA implement as I did and it worked.


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