NX6010 hydro transmission issues

[k0ua]

I wonder if the NX series, has it's charge pump for the hydrostatic transmission from the steering section flow. This is the way DK series works. There is no charge pump in the transmission, the charge pump function gets its fluid after the steering valve gets done with it then on to the oil cooler by the radiator, the hydrostat filter then into the hydrostat transmission. I am not sure where they tapped in for the DO3 valve for the 3rd function, but I would think it would be after the loaders PB connection and heading to the other selective control valves. This is fed from the larger section of the main hydraulic pump. Not the steering section. I am also having trouble understanding this. Other than the heat buildup. Of course the NX may not be the same as the DK either.

 

[MinnesotaEric]

Using the DO5 had nothing to do with the flow amount to the front disconnects for the grappler or other things. It is do to the flow going through the valve all the time leading to the rear remotes and three point system.

At first I thought I needed D05 too until I found the split pump spec in the service manual rating at 9.9 gpm making D05 unnecessary. Using D03 allowed me to mount on top of the transmission for maximum protection instead off offset closer to one of the rear wheels.

Anyway, a D03 open center with P open to T isn't restricting flow at 9.9 gpm. Even through the three valve stack in back, it is only adding 10 degrees.

Joe: You have a true 3rd function. Why they used a small valve is baffling because the entire output of the pump goes through the valve in an open center system.

For those who do not know, an open center hydro system is like a spray pump where the water goes round and round until it is needed, at which time it is diverted off in another direction by a valve. A closed center system is like the water system in your house: always under pressure and fluid doesn't move until a valve is opened. So at wide open throttle, Joe's tractor wouldn't be getting all the flow available. However, due to the other side of the pump servicing the HST and power steering, too small a valve body would't effect flow to the HST and power steering.

 

[countrybumpkin]

Do you know what valve they had at first, I can't believe they would have used something smaller then a DO3 the first time.

I couldn't get a good straight answer on the gpm I was getting 10 - 12 so I chose to go ahead and use the DO5. I had plenty of room to mount it up on the side of the trans out of the way. I did make a plate to cover the access opening to keep mud or debris out.

 

[MinnesotaEric]

Do you know what valve they had at first, I can't believe they would have used something smaller then a DO3 the first time.

I couldn't get a good straight answer on the gpm I was getting 10 - 12 so I chose to go ahead and use the DO5. I had plenty of room to mount it up on the side of the trans out of the way. I did make a plate to cover the access opening to keep mud or debris out.

I'm wondering if they didn't use a sub plate and instead used a double valve body with a pair of solenoids. Something like this: SAE 8 6 GPM DOUBLE SELECTOR VALVE 12 VDC P15544-2

We won't know unless Joe takes photos.

 

[countrybumpkin]

Yeah, I'm sort of curios now.

 

[kapper]

I'm wondering if they didn't use a sub plate and instead used a double valve body with a pair of solenoids. Something like this: SAE 8 6 GPM DOUBLE SELECTOR VALVE 12 VDC P15544-2

We won't know unless Joe takes photos.

OK, here's a picture. I spoke with the owner today. He said it is a 12 gpm valve, and they have ordered a 20 gpm valve. We did not get into the details, but presumably the whole 17 gpm is flowing through the entire system? Or does it have something to do with the location of the 3rd function valve? It is located on the passenger side just under the step to get up into the cab. I sure hope this works.... All I know is that when I start it and it is cold and I hit the pedals, they respond instantly. Then when it warms up it starts slipping, or having the delayed reaction. I also noticed the power steering is acting strange too.... Does this make sense??

 

[kapper]

OH, and he also said that when they get the new valve, that they have to re-work the hydraulic connectors and change them all up for some reason..... It won't be just simply swapping out the 12 gpm for the 20 gpm...

 

[countrybumpkin]

Well that's a DO3 valve , and sounds as if they are replacing it with a DO5. I'd really be curios as the the oil temp at the point in which it starts acting up. The valve should be plumbed between the loader valve and the inlet on the rear remote block. Eric said his Manual said 9.9 gallon flow on that part of the system. When I was asking my dealer and a few other sources I was getting answers from 10 - 12 gpm never could get a defiant answer so I went ahead and went with the DO5 just to be on the safe side. Mine is a gear shuttle so I have no clue on the hydro drive system as to where or how much flow is used for that part.

 

[countrybumpkin]

Only thing I can think they are doing that for is to match the valve flow with the new quick connects , looks like they have 3/8 on it know and will more than likely go to 1/2. I really don't see a need to do that but it's there decision. Only time that is going to have flow is when opening or closing the third function and unless your just opening and closing your third function 3 or 4 times a minute or more for hours straight, I can't see that adding much to the oil as for heating it up the valve itself has the oil flowing through it at all times so if it is restricting it for some reason that would build heat after a bit.

Do keep us up to date.

 

[MinnesotaEric]

OH, and he also said that when they get the new valve, that they have to re-work the hydraulic connectors and change them all up for some reason..... It won't be just simply swapping out the 12 gpm for the 20 gpm...

You have a sub plate that looks like it is a D03 size. Their mounting plate is pretty clever for getting it in there. Your entire system is sitting where I mounted a hydraulic "wiring loom" to guard the hydraulic lines and prevent them from getting into the HST pedal linkage.

My 3rd function requires three custom made plates, and four custom-length hoses just to plumb to the quick disconnects (not to mention the electrical harness that uses weatherpac electrical connectors) and is an order of magnitude higher in cost as a result.