Pressure Control Valve

[Tracy Ellis]

What is the valve needed for? I found a posting on here from 2008 suggesting the valve assembly can be removed. If removal is possible, what if anything will I notice. Just trying to decide if I should bother repairing mine or not. Thanks

 

[DavidP, South Wales]

Hello, Pressure Control is/was a device fitted to all UK 165 upwards and optional on 135 tractors. The Pressure Control Coupler shown on my 165 is a means of transferring weight from the towed trailer, discs etc onto the rear wheels to assist traction. If you fitted a PC coupler to a tractor without PC and raised the 3-point it might lift the front wheels off the ground when the coupler chain is correctly attached around the drawbar. The reason is that the tractor will deliver full lift pressure 2300 - 3000 psi to the linkage.

When used with a PC tractor and the quadrant lever is in the PC sector, hydraulic pressure can be varied from around 500psi to full pressure.

PC can also be used when using what we would call a topper, would it be a bush-hog for you?
If you are using it on soft ground the more of the machines weight can be carried by the tractor to reduce skid marks. It will not affect ground following ability.

It is possible to un-PC a tractor, it's not something that I have done. You will need a relief valve to fit to the pump.

My own choice would be to keep the PC.

DavidP, South Wales

 

[Masseynut(Australia)]

It is possible to remove and delete the pressure control valve, and I have done many over the years. I have done so because of the cost of repairing these if they are worn. I don't know the costing of the wearing parts elsewhere on the planet, but here in Oz, they are horrendous. I can tell you, the powers-to-be at Agco are going to retire well before I will.
First you will need to procure a standard stackpipe, without the "T" box attached. Then you will need to fit a 2800 PSI relief valve to the hydraulic pump, removing either the blanking plug or the existing 3000PSI valve. Now remove the pressure control valve, attached pipe and dashpot assy from the frame. Release the split pin from the clevis pin on the frame, and remove the pivoting actuating lever, and take off the barrel adjuster and spring assembly. The clevis pin can remain in the frame. It will not come out later and cause problems at any stage.
Your tractor will operate as per normal, less the variable pressure control feature that many farmers never use anyway.
Evan.

 

[Tracy Ellis]

Thank you David and Evan for the honest and knowledgeable replies. I think I am going to remove the PC system as like Evan said most farmers do not use it and I would not know how or when to use it to start with. This tractor has not done any major farming for twenty years or more and is mostly used for snow removal and property maintenance. Thanks again.