For years Iv pulled my 6 row 7200 planter with my 4440. This year I want to put my 6603 on it. The 4440 has closed center hydraulics and the 6603 has open center hydraulics. What do I have to install on the open center tractor to run the vacume motor so the hydraulics wont heat up? Is it as simple as just dumping the return oil to sump? or is another valve required?......

thanks

It has been a while since I had a 7200 but it seems like there is a section in the operators manual that addresses that issue. I am assuming you are talking about running a vac blower motor. If it is a finger pickup you should not have to do anything.

If the operators manual has a better idea than what I am going to tell you, by all means go with the operators manual.

Here is a flow control valve that will keep your oil from heating. It lets you adjust the oil to send the proper amount of oil to the vac motors under pressure and returning the excess back to the tractor via the return line or better an additional zero or low pressure line to the tractor sump (see tractor manual for an attachment coupler to do this). You would use this in place of the needle flow control adjusting valve that is on the planter now. The needle flow valve on there now just restricts the flow to the amount the blower needs. With a closed center system this is fine as the tractor pump adjusts itself to produce only the flow (gpm) needed to do the job. In an open center system the pump puts out a constant flow instead of a variable rate flow. The planter blower would be ok because the needle flow control valve would still limit the flow to the motor but since the pump on the 6603 would be trying to push full flow (maybe 16 gpm or so?) through the system that only needed about 4 or 5 it could not do it and would cause the relief valve in the tractor system to blow off the excess flow. The planter wold work fine but the tractor would be bypassing so much high pressure oil it would overheat and prematurely wear out your pump and relief valve (a bad thing). Not to mention using a lot of extra fuel when that hydraulic pump was drawing a constant 15 or 20 horsepower to drive the overworked pump. This adjustable flow control valve lets you adjust the lever to give the right amount of oil to the blower (you would adjust the vacume with this lever) and bypasses the rest at low pressure back to the return. Like I said, this valve would replace the original needle valve and you would have an additional return line to plumb into a low pressure return to the tractor sump or valve body.

If you wanted to be able to go back to the 4440 you could either set the new flow control valve wide open and use the tractor flow control to adjust the vac level or set the flow on the 4440 open enough to ensure adequate oil flow and still use the new flow control valve.

Fairly simple and inexpensive fix to be able to use both tractors.

You might have to play with which outlet to use on the 6603. One probably has priority and you need to choose the one where the planter will raise without cutting the blower motor completely out when raising the markers or planter.

A good JD mechanic could probably give more insight to the tractor and planter workings but good mechanics that actually UNDERSTAND how these systems work are hard to come by. Some can turn wrenches and replace parts but a precious few actually understand what is happening within.

John

For what it is worth those 6603's look like a sweet little simple inexpensive tractor. They don't have a lot of frills but our little 5303 is a well liked tractor around here. Simple, basic, but get the work done. I would not mind having a 6603 with cab, mfwd and loader. Look like a darn good value machine.

John 

Before you order any parts, please talk to someone who knows that tractor's hydraulics. I don't believe there is any kind of priority valve on that tractor. You won't be able to run the fan motor and lift the planter and markers at the same time.

I just found a bulletin where Deere says you should use a pto driven pump instead. Quoted:

Complaint or Symptom:

6003 series tractors are not compatible with hydraulic motors.

Problem or Situation:

Due these tractors having an open center system, it is not recommended to install hydraulic motors since hydraulic pump would fail.

Solution:

In order to run hydraulic motors on these tractors a PTO driven pump should be used.

For planters the following bundles are available :

• Bundle BH78508 (Auxiliary 540 rpm PTO-drive hydraulic system)
• Bundle BH78873 (Auxiliary 1000 rpm PTO-drive hydraulic system )
• Bundle BH78741 (Oil cooler)

End quote.

There are ways to make hook a planter motor to an open centre system, but it involves hooking between the pump and the tractor's valve stack. Basically, you run the oil from the pump to the planter motor, with a diverter valve to the valve stack (it sends the excess oil the motor doesn't need to the valve stack). You control the fan motor speed with the diverter valve. Depending on where the system relief valve is, you may have to add one to the supply line (before the diverter valve) in case the hoses disconnect. The relief valve would dump to sump if it trips. You also need to hook the hoses together when you disconnect the planter. Oh yes, the fan motor runs all the time the tractor is running.

How do I know all this? I once had a customer who wanted to be able to switch between open and closed center tractors and didn't want to have a pto pump. Neither the tractor or planter were Deere, but the principles are the same. By the time all this was put together, the labour and material came a long way toward the cost of the pto pump. And that didn't include anything for my time researching how to make it work.

The flow control valve I listed should solve the problem of damaging the pump. The only thing I am not sure about is that when he raises the planter it may rob all the fluid from the the blower and cause it to loose vac and drop the seeds out of the cells causing the planter to plant several feet till the seeds are picked up again. That is why I suggested talking to a JD mechanic. But as far as running the vac with an open flow system, as long as the flow control valve will handle all the tractor flow (rated GPM) and the excess flow port of the flow control is routed back to the tractor return, there should be no way to hurt the tractor running a hydraulic motor as long as it has a transmission cooler. The flow control valve simply lets the excess flow (what the motor does not need to turn it the proper speed) flow back to the return, just like putting a hose from the outlet to the inlet of a remote outlet and pulling the valve to the on position.....oil just flows freely around the circuit. We have used these valves in a lot of different situations, both on open center systems and on closed center where the tractor flow control controls the volume of oil to the flow control valve that is operating in essentially an "open" circuit.

John 

No problem with what you said, John. I really wanted to reinforce the message to talk to someone who knows that tractor before spending the money. I did a DTAC search on the issue and was surprised to see such a blunt message saying "don't do it". Usually, the message is more like "we don't recommend it, but if you really insist, here's what you have to do".

My recollection on this issue (goes back at least a dozen years, and was different brands to boot), was there definitely would be a time when the fan motor would slow down or stop. I'm thinking about when you lower the planter and markers, there would be very minimal pressure required, so the oil would go through that valve before the motor valve.

If the tractor has the right valves, an open centre system can work running a motor and lift cylinders at the same time, but I don't think this tractor does. 

Doesn't the flow on an open center system go through all of the SCV in series?   If they are in parallel I would think any time you tried to do two things at once it would not work. 

It seems a little odd that DTAC would say that running a hydraulic motor on a open center system will ruin the pump, and then they go on to recommend running it on a PTO driven system instead.....such system almost certainly being an open center system as well.....

I sure hope we can run a vacuum planter with an open center system because we just spent two days plus putting one on our 35 to run our 1200 CIH planter fans with.   

My hydraulics theory and application knowledge is getting really old. However, I think the key here is the ability to do two things at once. Your planter pto pump only has to do one thing, and the pump is sized correctly to the application (I presume).

It's not the same as trying to run a fan at constant speed and also try to provide raise/lower and do all this without causing heat issues. To do that on a fixed displacement hydraulic system with the typical open center scv's isn't easy (I presume you've found that it isn't easy even on a pfc system since you're going to a pto pump on that tractor!) That's why I was saying you would need to use a "power beyond" method bypassing the valve stack for the fan motor.

I truly was expecting to find a method in Deere's service information (it could be there and I missed it) to cobble up that planter fan motor to that specific tractor and have it work for both lift and fan speed. I've done it before with the method I described. Maybe I was being too cautious. I'd want to have someone with strong practical experience on a simpler method advising me if I were to try anything else. I still stand by my advice to use a pto pump in this situation.

edit: ordinarily I would have left this topic alone because I don't know enough about the specific tractor in question. However, the OP specifically said he was going to go and spend some money that I felt wasn't going to be the complete answer. My main intent was to highlite that more research would be needed to be sure of what would work on that tractor. 

Omar may be right.

I have no problem running the fan with the open center system as long as a person uses either A. a motor that is sized for the flow that the tractor pump is putting out which is not the case here (fan motor uses 3-5 gpm and tractor is probably something over 14) or B. a method is used so part of the flow can be directed to the motor and the excess can be directed back to the sump. This is why I recommended using the flow control valve in the link I gave and I have no problem believing it will operate the blower motor properly with no harm to the tractor pump. We have used and I have seen these valves used in numerous applications on open center systems (what they are actually designed for) and closed center systems where the tractor is diverting a portion of the total flow to these valves in an open center fashion. The other problem can be heat generation running a motor continuously if the tractor is not equipped with a transmission cooler which I do not know if this tractor does but all the 4 cyl 5000 series tractors do so (some or all of the 3 cyl 5000's do not) I would assume it does.

But Omar hit the nail on the head when he started talking about an open center system having trouble doing more than one task at once. This is where the trouble will come in. Most likely at best the blower motor will slow when the planter is raised and at worst it will stop, then restart when the planter is finished raising, causing seeds to fall out of the cells and the planter leaving a skip for the first however many feet till the cells get filled.

The method Omar describes capturing the oil between the pump and the tractor valve/3pt most likely involved using a flow control valve to divert part of the oil to run the blower and allowing the excess to flow on to the tractor hydraulics, allowing both systems to operate at once but with reduced capacity to the lift system.

Some open center valves can do multiple functions at once. A backhoe valve comes to mind. The problem is the only way to know how the 6303 valve would work trying to run the blower and lift the planter would be to try it and that may not be acceptable to the owner. At best the blower motor is probably going to slow when raising the planter.

The flow control valve will work running the fan. Running the fan and lifting the planter both successfully at the same time may not be possible.

Sorry for my misleading post and thanks Omar for trying to keep someone from making a mistake.

John

One other thing I thought of when the DTAC solution said "don't do it".

Sometimes "don't do it" might mean they don't know how to do it. Although pretty sharp guys, they may not know everything.

Sometimes "don't do it" might mean it is way more trouble than it is worth so other solutions are better, don't waste your time.

Sometimes "don't do it" means that it will cause damage to your system.

Unfortunately DTAC in this situation didn't explain why to "don't do it". They just said that the open center system is not compatible with hydraulic motors. That seems kind of funny since Hypro and Ace sprayer pumps make hydraulic driven sprayer pumps specifically designed for open center system tractors (they either have a big enough motor sized for the oil flow of the tractor or an internal metering needle valve that you can open to divert excess oil flow).

One potential problem I just thought of. If this tractor relies on the flow of hydraulic fluid through the remote valves and 3pt to dump in on top of the transmission or rear end for lubrication purposes, potentially diverting the oil continuously out the hydraulic outlet might not dump the oil back in the same place that is needed for lubrication. The oil coming back in the return side would go back to the sump but it might not go the same place as when the oil is flowing freely through the open center system and not being used. With normal hydraulic use that is mostly intermittent this would not pose a problem, diverting the oil on something continuous might be. I don't know. I think this is a very remote possibility but just don't know. Just something I thought of that could be a reason they said to "don't do it". Would have been nice if they gave an explanation of why not to do it. I sure do not want to cause the tractor owner grief.

John

You know John, when I've got you and Mark questioning something I said... Well, let's just say I was about ready to book the day off work and figure out where I was going wrong! Even though I've had some experience in a shop, and took hydraulics and electrics as personal challenges, most of that was back in the 80's and I've had almost no opportunity to dig into that stuff since.

I have the same thoughts about the way DTAC presented this "solution". Tell us why so we don't go down a lot of deadends trying to figure out another way. It was obvious to me this particular bulletin was quickly written. I fixed three spelling mistakes before I posted the excerpt.

I think you've brought up the big concerns with heat and possible lubrication issues. I'd venture heat as being the primary concern. Maybe a cooler on the planter would help. It keeps going back to the issue that by the time you make everything work right, using a pto pump would be much easier and about as cheap.

Omar, don't take my questions the wrong way.  My interest in the issue is on a broader scope then just the question posed because I was working on a similar question myself at the same time. 

Did I ever mention that I hated the priority valve (really pretty much the whole hydraulic system....and the wiring too, while I'm at it) on the row crop Challenger?  Thought maybe someone might have missed that

I didn't take it personally. I've learned over time that when I think you're asking a simple question, you're really getting at something deeper. If I don't know what it is, I try to step back and understand what I was missing.

Back in October '95, I started with the Challengers. The second day on the job, I flew to Tucson for training. I think the first session I was in, the instructor (who I got to know fairly well over time as a straight shooter) walked into the class and said something to this effect. "Boys, we've got a problem with the hydraulics on these tractors". That impressed me. I had never heard that kind of statement before or since at a company sponsored event. It could have been as simple as the Cat engineers not liking something done by the NH engineers, but I think at that point they already were realizing the limitations with priority valves. They didn't have the option, because of the steering pump, that the blue tractors had which was to use the second pump to solve some of the issues. It took some three years before they got most of the issues with the valve stack resolved. That is, other than the twisting on a cable to adjust flow issue!

Sounds like a good safe idea.

John