Bleeding Hydraulics on a John Deere 2640

[JohnGough]

I am about as much use on mechanical issues as a trapdoor in a canoe. As a result I bought a JD 2640 and, of course, it's spent more time at the repair shop than running. My latest set of connecting issues is that I had to buy a new tire. I lifted the wheel using the bucket. Just before I took the wheel off I almost ran out of diesel, so I put in 5 gallons. When I went to put the wheel back on, I couldn't lift the bucket because the tractor wouldn't start. It turned over but wouldn't fire. I read my (next to useless manual) and determined how to bleed the fuel line. Miracle of miracles, the tractor started. However, when I tried to lift the bucket, none of the hydraulics worked. So, I added Hydraulic fluid, started the tractor and the hydraulics didn't work. Then, suddenly the 3pt hitch raised and the hydraulics worked. I lifted the wheel and put the axle on blocks so I could put the wheel on. After struggling for an hour I found that it was a 2 man job. Contacted my neighbor who came over this morning and we were able to put the wheel on. I started the tractor and tried to use the bucket to lift the wheel, and, no hydraulics. I've read the manual, and quite frankly, it could be written in hieroglyphics, for as much as I understood it.
Can anyone please help simplify how to bleed the hydraulics or tell me what else it might be?

 

[oldjohndeere]

You don't bleed the hydraulics. I have a 2630 and it does the same thing every time it is started after sitting. The hydraulic fluid is bleeding back away from the pump, just let it run a couple minutes till it picks up oil again. Mine has done it for years.

 

[used red MN]

Hello John, welcome to YT! I think this applies to your tractor. If when you start it and continually hold down the clutch this hampers the operation of your hydraulics. There are two pumps working sort of in unison to provide the hydraulics in your tractor. A transmission lube pump and a high pressure main hydraulic pump up front driven off the front of the engine. The transmission pump moves fluid to a reservoir over the main pump up front. When the clutch is pushed down the transmission pump stops so there is no oil supplied to the main pump reservoir, so if it has no oil it cannot pump. You might say that is dumb design, maybe in a way it is. This might be a bit complex but you need to understand your tractor has a closed-center hydraulic system. This means that when no oil or flow is needed the pump does not pump any oil so that is how the small reservoir up front keeps the main pump supplied in most instances.
If this does not apply to your tractor someone will be along to correct me.

 

[JIM MN]

used red mn; you are correct.... I'll add; start your tractor, running , take your foot off the clutch pedal.. Also look at your operators manual for how to check your " hydraulic oil level.." It is a Dubuque made tractor.. checking hydraulic oil is different?????

 

[JohnGough]

used red mn; you are correct.... I'll add; start your tractor, running , take your foot off the clutch pedal.. Also look at your operators manual for how to check your " hydraulic oil level.." It is a Dubuque made tractor.. checking hydraulic oil is different?????

I have plenty of hydraulic fluid. The problem is resolved but completely by accident. I fiddled with it for an hour then sat on the tractor and decided to give up. I turned the key to the off position in preparation for removing it, and suddenly the PTO raised and all the hydraulics worked. So if I start the tractor and remove the key, everything works. It was never like that before but I'm happy to be able to use it.

 

[JohnGough]

Thanks for your replies . I appreciate you taking the time

 

[Jim.ME]

I have plenty of hydraulic fluid. The problem is resolved but completely by accident. I fiddled with it for an hour then sat on the tractor and decided to give up. I turned the key to the off position in preparation for removing it, and suddenly the PTO raised and all the hydraulics worked. So if I start the tractor and remove the key, everything works. It was never like that before but I'm happy to be able to use it.

You tried this several times and it repeats the same? Switch or something electrical going bad? You may have more problems coming.

 

[used red MN]

“I turned the key to the off position in preparation for removing it, and suddenly the PTO raised and all the hydraulics worked.” And you better put on your TIN HAT as well. Sorry John, I know you are new here but I had to do this! I am going to give a lot of folks a good laughs at your expense. Please forgive me but sometimes when dealing with mechanical things you have to stop and get a good laugh when the opportunity arises. There is absolutely, positively and most non-equivocally no connection between the key being turned off and the hydraulics starting to work. Did you take your foot off the clutch prior to turning off the key? That is likely what restored your hydraulic functions! Again sorry!
Came back to edit by adding.. unless someone has added some type of electrical operated hydraulic apparatus to your tractor, only this could possibly cause a correlation between anything electrical and hydraulic on your tractor.

 

[Harry in Ky]

https://partscatalog.deere.com/jdrc/sidebyside/equipment/59839/referrer/navigation/pgId/247767

Look on the hydraulic pump and see if you find something like this. That would be the only thing I can think of where anything electrical could influence hydraulic operation. If you find this unplug it and try it again. Something shorted in the wiring could possibly cause your symptom.

 

[wore out]

“I turned the key to the off position in preparation for removing it, and suddenly the PTO raised and all the hydraulics worked.” And you better put on your TIN HAT as well. Sorry John, I know you are new here but I had to do this! I am going to give a lot of folks a good laughs at your expense. Please forgive me but sometimes when dealing with mechanical things you have to stop and get a good laugh when the opportunity arises. There is absolutely, positively and most non-equivocally no connection between the key being turned off and the hydraulics starting to work. Did you take your foot off the clutch prior to turning off the key? That is likely what restored your hydraulic functions! Again sorry!
Came back to edit by adding.. unless someone has added some type of electrical operated hydraulic apparatus to your tractor, only this could possibly cause a correlation between anything electrical and hydraulic on your tractor.

X2, As it left the factory there's NO "electric over hydraulic" functionality on that tractor UNLESS someone has installed an "electric hydraulic pump destroker" and it's wired wrong or there's a short in the wiring!

 

[wore out]

https://partscatalog.deere.com/jdrc/sidebyside/equipment/59839/referrer/navigation/pgId/247767

Look on the hydraulic pump and see if you find something like this. That would be the only thing I can think of where anything electrical could influence hydraulic operation. If you find this unplug it and try it again. Something shorted in the wiring could possibly cause your symptom.

You beat me by a half a minute, Harry!

 

[used red MN]

John per “trap door in a canoe” FYI, if you didn’t know as I mentioned in my other post the hydraulic pump is up front below the radiator driven by the front pulley of the engine. Seems like these guys are poking a few small holes in my assuredness, but that would be considered an “add on part”

 

[Fixingfarmer]

I think you two have a winner! So my question is when key is in run why does it have power to the destroker? What has changed? Honestly put a manual one in there and be done I’ve had 2 tractors with them. I have never turned the screw figured it was more trouble then it was worth I’ll go get a bigger battery off something rather than deal with that and forgetting it or it getting stuck somehow. Time better spent having a functioning block heater.

 

[Fixingfarmer]

And yes it is absolutely rediculous that the one gallon green surge tank is the amount of oil on top of the pump when you need to lift the bucket so when you lift the manure all the way to the top and dump into the spreader you are stuck and you don’t have any juice unless you pop it into neutral and wait. It lifts better going full throttle down the road than when used in normal loader operations.

 

[Harry in Ky]

I think you two have a winner! So my question is when key is in run why does it have power to the destroker? What has changed? Honestly put a manual one in there and be done I’ve had 2 tractors with them. I have never turned the screw figured it was more trouble then it was worth I’ll go get a bigger battery off something rather than deal with that and forgetting it or it getting stuck somehow. Time better spent having a functioning block heater.

That's one opinion. There are others.

 

[JohnGough]

Wow . what a lot to try.. the irony is that I've got our 42 acre Ranchette up for sale and we're moving to a MUCH smaller place to enjoy retirement, so I'll be either selling the tractor or leaving it with the property.
I am absolutely certain that when the key is in the "on" position the hydraulics will not work. When I take it out or put it in "off" they work. I had a friend come by this afternoon, who did not believe me. So, I got on the tractor and showed him.
"used red MN" thanks for dumbing down the location of the pump, and I'm usually the one making fun so I've probably got it coming.. The other ways of describing my mechanical abilities are that I'm as useful as an ashtray on a motorbike or a chocolate fireguard.

 

[Harry in Ky]

Look for the solenoid. If it's there unplug the wires and try it again. Why is that so hard to understand? IF that's your problem, it will be easy to solve.

 

[fdt860]

The supply pump.is live on those tractors, if I amnot mistaken.

 

[Fixingfarmer]

Look for the solenoid. If it's there unplug the wires and try it again. Why is that so hard to understand? IF that's your problem, it will be easy to solve.

That’s a way to test. Not fix. What’s at the other end of the reason power is going to it at all. Something is shorted or??? Is the starter also engaging when it’s not supposed to

 

[Fixingfarmer]

The supply pump.is live on those tractors, if I amnot mistaken.

Yes right off the front of the engine and will pump until builds pressure. Unless there is an electric solenoid on the front left it will disable the pump until the starter button or switch is released