Hydro won't move
 

Hey fellas I just changed the filter and fluid in my new 125 and now I can move about a foot in reverse and nothing going foward. I changed everything because the gasket was slightly leaking and it'd never been change yet since I owned it. Any ideas what the problem is I'm very new to this.

What filter and fluid did you use..???

And how much fluid did you put in?

It's the correct trans filter and I put just shy of two gallons of hytran. I filled till it poured out the fill hole. Ran it for a while tried to move it foward and reverse then topped it off.

Is the lever for the pressure relief valves on?

Is the "input shaft" to the hydro unit rotating..???

The input shaft is spinning and the lever is in the drive position.

Did you clean out the rearend good When you drained it? It sounds like a plugged filter or the wrong filter.

I cleaned all the gunk out then sprayed with brake cleaner and wiped it all down. The filter is from ihccw and says it's for a cub 125 hydro. I'm 90% sure it's the correct filter unless I was sent the wrong one it says it right on it though.

It seems like you did everything right.

I don't think it's the relief valves sticking because it'll move a little in reverse then stops and now will creep for a foot or so foward.

When you cleaned the transaxle out was there a lot of loose gunk in there? And just throwing this out there, because it could happen. Did you use paper toweling to clean it out, and possible left some toweling behind.
Easy thing to do, been there done that. Either way sounds like others have mentioned it seem like a plugged filter, or wrong filter.

Maybe there is air in the system and when you move the lever back and forth ( when running ) it's starting to bleed the system.

( any comments on that line of thought? )

I wonder if one valve is stuck partially in relief and not allowing pressure to build up.

I was thinkin about air is there a way to bleed the air out of the system.

I'm thinking the hydro pickup tube is clogged with crap.

I was under the impression that the vent would prevent air in the system.

What would be the next step you guys think to check off.

I think you need to check the relief valves and see if they are coming up. This system is "self bleeding" there is no way it is air locked, unless the charge pump is bad, or there is an air leak in the suction side. The old gasket came off with the filter right? Pull the filter and make sure something isn't plugging it. Know a guy who wiped out the trans with a rag and a piece of the rag tore off and got left in the trans. Plugged the filter. When he pulled the filter off he found it. Again, check the relief valves. If they aren't coming up, pull the filter back off.

:biggrin2::bigthink: Jonathan, I think I know that guy also:beerchug:
Actually it should of been a rag instead of paper towel.

I wasn't going to say who it was...... :biggrin2::biggrin2:

Was it working properly before you changed fluid and filter?

Ok update. It's moving now but very sporadic. I'll have the lever all the forward for up to two minutes, then all of a sudden it'll take off, ride for maybe 50 yds then stop. Then without ever moving the lever, after a few minutes it'll take off again. The same situation in reverse. Now do you think both of the relief valves could be sticking or maybe somethings clogged. If clogged will I have to drain all that expensive fluid, clean and try again? I'm hoping it'll blow itself clear haha. I pulled the filter off and it was not clogged with anything I could see but after reinstalling is when it started moving.

I would change out the Hydro Filter first, before changing fluid.

I think one of the valves is stuck open and not allowing the pump to build up enough pressure to consistently move the tractor. If the valve was open just a little that's all it would take. I would take the valves out and give them a good cleaning.

The filter I have is part number 923 3014 is this the correct filter?

Does the tractor have to be split to access the valves or is there any other way to access them?

I've never done it to a nf so, I'm not sure. Maybe you could take the seat pan off and at least be able to look in there to see if the valves are popped up.

Ok I can see both plungers on the valves and coated them with wd4o. They both move up and down fairly freely and seem to return to all the way up. I don't know what they are supposed to do when the lever is pressed forward or reverse but they are not doing anything. Heres a little video you can't see the valves in it but maybe you can see something I don't.http://www.youtube.com/watch?v=VBqykNP1imo

The release valves look to both be in the operational state meaning buttons are up in the air. I would jack up the rear of the tractor and remove the pick up pipe and see if hydro fluid comes out of the trans. I would put a catch pan under there so as not to lose any fluid. Still sounds to me like you have a plugged pick up hole or the tube itself is plugged up. If it worked before and not now it is not pulling oil. I can see the stub shaft on the back of the tranny spinning so it's deff not a toasted spirol pin and the trunnion is moving back and forth which is another good sign. Start with the first things first. No oil being picked up means no movement. What brand oil filter are you using? Oh the little buttons are suppose to be up all the time even when tractor is moving.
:bigthink:

personally I would say filter but that is just me

http://www.ebay.com/itm/like/300886411597?lpid=82 This is the filter I have. My po took a piece of copper pipe and has a 90' with a compression coupling connecting to the pick up tube. Could I crack that coupling loose and see if fluid is coming out of there, and if it is where else could it be clogged? If it did I would have fluid from the trans making it through there and all the way to the filter because when I pulled that it was full as well. It couldn't be the filter because I tried the original filter and the new one with the same problems.

I would just take the pipe completely off and check it. Like I said put a pan under there and catch the hydro fluid. You need to start at the source and work forward. We know there is oil in the resevoir now you have to make sure there is a clear passage for the oil to get pulled to the pump. Either it is plugged at the axle housing or the tube is clogged. Correct filter also.

Yes that is the correct filter. I agree with Kelly (cubs-n-boxers), if it was working before, and everything is "spinning", then it probably isn't picking up oil. Either tube is plugged, or filter is.

This might be the issue.

The NF Cub Hydros, had this "Suction Tube" for the oil return. From what I ever gather about this, the IH engineers thought this extra tubing would "cool" the oil down before it returned to the Charge Pump.

http://i176.photobucket.com/albums/w...3.png~original

The engineer's changed the design to a simple "L" shaped configuration start with the 1x8/9 series hydros. It was a two piece design. When the Quietline Series came out, they came up with a one piece suction tube as seen like this.

http://i176.photobucket.com/albums/w...f.png~original

I am wondering if something isn't in this suction tube, and that fact that the oil has to take the "scenic route" isn't causing your problems. As a suggestion, you may want to upgrade this suction tube (which is still available) to offer better oil return.

Are you SURE the pin isn't sheared in the coupling and it is just turning the hydro a bit, some of the time?
It would not be the first time that happened!!!!!!!!!:bigthink:

He said he checked on post #7

Maybe we should rephrase the question. Is the Hydro unit output shaft spinning the same RPM as the input shaft...??? :Huh:

The tube is not a return, it's a suction line, it feeds the oil to the filter. The early style has been known to become air bound. Just my 2 cents but I would loosen the filter, remove the plug on the rear cover and then blow some low pressure air into the case through the fill hole to hopefully prime the tube. You have to go easy doing this or you could hurt the seals in the rear end and pump. I'd use one of those vacuum cleaners that you can use as a blower. As soon as you get oil up to the filter tighten the filter and stop pushing air into the trans. I recall ksmith having a problem getting one of his tractors with that style tube to prime a couple years ago.

In the HVAC/R world.....it is the SAME THING...:biggrin2:

LOL! :biggrin2::biggrin2:
That it is Roland! LOL!
But in hydraulics, Sam is correct. :beerchug: