Problem with Lift Tilt Dump...

[J_J]

I may also be using the wrong words. But no, I have 3 pumps. One wheels, one PTO one steering, lift and brakes (did not know brakes were in this circuit).

I have a pressure gauge on the brakes so I know I am getting the goods.

Just got off the phone with Terry. Thought is that it might be back to the relief valve in the PTO block. His thought is that the brakes need only a bit of pressure, and that is what gets by the valve, but not enough to drive the steering and lift.

We will see. He wants me to get the tractor cold, start it, and cycle the brakes 5 times. See if the pressure drops.

Carl,

If what you said is true, [ one steering, lift and brakes (did not know brakes were in this circuit)], after the accumulator has zero pressure, take the line off to the accumulator and cap the line and plug the accumulator, and see if you have the correct pressure for the steering and lift. You did say that the relief valve look good, but was it working correctly.

 

[woodlandfarms]

I did not know that my brakes were on the steering circuit as well. I talked to Terry about a schematic. He said they are finally starting on working on one. that said, I know that the 2008's have some differences from my 2002.

Whatever...

Terry has gone over to the engineers. We are going to do a conference call tomorrow morning. Terry is completely stumped. He feels it is something in the Accumulator.

Also, it seems heat related. Once the tractor warms up I no longer have the problem.

 

[BobRip]

The people at POWER-TRAC must be laughing their as* off at us trying to figure out just what and how they did things. If I were a lawyer, I think that I would start a class action suit involving everyone that had ever purchased a PT, demanding that a service manual be provided to every owner with complete theory of operations, pictures, and schematics for every model and modification they have ever done. They rely on one person to answer all our questions. I don't think most of us would have to call and ask questions if we had decent owners/service manuals and parts manual. They must be afraid or ashamed that they do not know how to make/design a good service manual. A good owners manual is availiable all the time, and we don't put them in a lockup over the weekend either. They get a -5 for technical manuals, and schematics. If every new prospective owner would demand a comprehensive and usable manual with their machine before they purchased, PT might get off their as* and provide same.

.

PT would just go out of business, restart with a new name, the lawyer would make money and all of our machines would be worthless. We would still not have manuals. Nobody wins a lawsuit except the lawyers. Remember, the legal system was created and fine tuned by lawyers and for lawyers. (I wonder if this will be deleted).

 

[woodlandfarms]

(I wonder if this will be deleted).

Just you Bob. I would hunker down for a few months. Make as few waves as possible ;-)

 

[toy]

Woodlandfarms does your machine have a brake that works like a car brake [apply pressure and it stops] or is the brake you are talking about one that when you start the machine it builds up pressure and releases the brake and when you shut off the machine it automatically sets the brake and it has a lever that when you turn it it will set the brake while the machine is running or some version of that? Just curious our 425's just have a parking brake that has a pin that engages a cog on the front wheels, nothing to write home about. If yours is a brake that builds up pressure when you start it up and releases and when you shut the machine down it sets the brake. If that is the way it works I have seen that system before. The ones that we had, had one hose that came up to a ball valve and then to a master cylinder and then teed out to each of the brake disks. With that system you could while the machine was off cut the ball valve off[that blocked the oil from going back to tank and then the master cylinder had a hand pump on it that you could pump up the brakes to move the machine when it was broke down. The machines that we had had electric traction motors and the disc brakes was hooked up to the shaft on the electric motor and then a drive shaft to each of the wheels. How is the disc hooked up to the wheels on your machine?

 

[SpringHollow]

the brake you are talking about one that when you start the machine it builds up pressure and releases the brake and when you shut off the machine it automatically sets the brake and it has a lever that when you turn it it will set the brake while the machine is running or some version of that? ... With that system you could while the machine was off cut the ball valve off[that blocked the oil from going back to tank and then the master cylinder had a hand pump on it that you could pump up the brakes to move the machine when it was broke down.

That is the kind he has.

Ken

 

[J_J]

I did not know that my brakes were on the steering circuit as well. I talked to Terry about a schematic. He said they are finally starting on working on one. that said, I know that the 2008's have some differences from my 2002.

Whatever...

Terry has gone over to the engineers. We are going to do a conference call tomorrow morning. Terry is completely stumped. He feels it is something in the Accumulator.

Also, it seems heat related. Once the tractor warms up I no longer have the problem.

Carl,

While thinking about your brake system last night, I thought perhaps they did use the steering pump for this reason. The drive pump only produces pressure and volume when the treadle is activated. The steering and lift pump is a gear pump and is producing pressure and volume all the time. So from an engineering stand point, why not use the steering pump to charge the accumulator. Some one had mentioned something about a shuttle valve in one of the circuits that wore out and caused problems. Anyway, a test gage applied throughout the path of the hydraulic fluid would help to analyze the situation, and come up with a logical solution.

However, after looking at the schematic for the 1850, the accumulator looks like it is supplied by fluid from the top of the drive pump. Now the question is after you start the engine, without touching the treadles, does the pressure build up in the accumulator. What I am trying to get to is,
does the accumulator charge from the drive pump at rest. Maybe you have a bastardized experiment version from our good folk at PT.

 

[J_J]

Bob, Do you have a hydraulic schematic of the lift/tilt circuit for the 1850?

 

[Bob999]

Here is the diagram of the lift/tilt circuit.

 

[MossRoad]

Must be something in the Tazewell water.

I think the chemical name is a radio active element... confusium.