testing hydraulic pressure on MF135

[martin rock]

Hi All

I want to test my pression because I want to add a new remote for a log loader that requires 2300psi and 5 gpm. I suspect I will be a little short on gpm since the tractor manual says 4.5 gpm at 1700 rpm but I think I can live will a slower speed. I already have a diverter valve on the tractor (see picture) to select between my 3point hitch and my FEL. The hose coming from the diverter valve goes into my control valve for the FEL. I already took a reading of the pression at the control valve and it was 2000psi . Although the control valve started screaming at about 1500.

My question is: is it safe to test the pressure directcly at the diverter valve while I am at constant pumping? I suspect the releif valve in the tractor hydraulic will prevent any damage, but just want to make sure.

If I can get the proper pressure I plan to add another diverter valve connected to the already installed one to select between the FEL and the remote log loader.

thanks for your comments

Martin

 

[shaeff]

Have you considered adding a front mounted hydraulic pump? Not really what you asked, but will provide all the gpm and pressure you need for the loader (will be much better) and for the log loader as well.

 

[martin rock]

My fel is not fast but I don’t use it for a living and I got used to the slow speed, I guess it will depend on the log loader action. It does have 3 inch cylinders as opposed to 2.5 for my fel but again the fel has 2 cylinders working together. I think I will consider the front mounted pump if it turns out too slow for my liking, thanks for the comment. Is this an easy job to do?

 

[Dave M7040]

Which relief valve were you hearing noise from? The one in the loader valve or somewhere else.

Installing a front mounted pump requires you to provide a reservoir and return filter in addition to connecting the pump to the crank shaft.

A new loader valve with a power beyond feature to feed the log lifter would eliminate the need for a second diverter and allow both the loader and lifter to work.

Dave M7040

 

[martin rock]

Dave, The screaming came from the fel control valve when i tested the pressure. I will likely not use both fel and log loader at the same time. My guess is that a second diverter valve will cost much less than bying a new control valve with power beyong. But I will keep this idea as an option. I still need to know the pressure coming from the tractor hydraulic pump

 

[Dave M7040]

Dave, The screaming came from the fel control valve when i tested the pressure. I will likely not use both fel and log loader at the same time. My guess is that a second diverter valve will cost much less than bying a new control valve with power beyong. But I will keep this idea as an option. I still need to know the pressure coming from the tractor hydraulic pump

I am always reluctant to say with certainty on a tractor I do not know.

My concern is dead heading the pump and causing it to fail.

If there is somewhere you can measure the hydraulic pressure when the diverter valve is not sending oil to the FEL then that would ensure the internal relief valve is still in the circuit.

Alternatively, if you connected a Tee to the diverter line now going to the FEL, install the test gauge in one branch of the tee and in the other put a valve so that oil is discharging into a bucket or use the loader return line. Then slowly close the valve while watching the pressure rise. .

If the pressure stops rising then you are seeing the relief valve in action. You never want to close the valve completely to avoid the pump pressure going too high

Use hydraulic quality valve and Tee not plumbing stuff.

Dave M7040

 

[Agvg]

No problem, the pressure controll are before this valve, the hydraulic on a MF of this type is very different from all most all other tractors, there are no valves and you controll the output of the pump by regulating the pump directly.

 

[martin rock]

Dave, you mean adding a second diverter valve?

AGvg: Doesn`t the MF135 has a relief valve in its hydraulic? what regulates the pressure when the position control level is placed at the constant pumping position?

thanks guys

Martin

 

[Agvg]

Some has a classic relief valve, some has a pressure sensor that regulates the pressure from the pump when it reaches maximum pressure.

 

[Agvg]

But there are no way to dead end the pump and damage it, but it sure can make a lot of knocking noise when it hits max pressure.