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Morooka Mk160

Forresthyd

New Member
Joined
Mar 10, 2021
Messages
3
Location
Scotland
Hello HEF, have some head scratching queries about trying to modify a morooka Park brake system.

Already undergone some major modifications to the machine involving twin pumps capable of a combined output of 260ltr/min at 2000rpm.
Now getting rather stumped trying to change the park brake to having an electric Activation or some sort of remote valve.

The machine is modified to be driven externally as well as from in the cab. And trying to ensure safety by having the park brake work on a deadman style system.

The drive control levers are spring return and work well but really needs to be onto a deadman.

Currently have a system working of a shutoff valve installed into the system on the rear of machine that allows the brake pressure to be released when open, and when closed have installed a valve to essentially re-energise the charge pump side of the brakes working off a switch. This works with the factory park brake switch in the off position.

Any help or pointers in this would be greatly appreciated.

Many Thanks, Gregor.
 

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lantraxco

Senior Member
Joined
Jan 1, 2009
Messages
7,704
Location
Elsewhen
I'm not clear on what exactly you're trying to accomplish, but a simple three way solenoid valve, if the machine is not equipped with one from the factory, or add one in series, or parallel with a shuttle valve, with the factory one, will take care of the brake function. Lots of possibilities either electrically or hydraulically to work together with the factory setup.

If you want to safety the drive pumps, and at the same time lock up the park brakes, just install a large energize to open two way valve and dump the hydrostatic charge pressure off to the cooler and back to tank, when the pumps lose charge pressure the servos will spring return to neutral, if you install the dump valve(s) before the tap for the brake release it will also cause the spring brakes to apply.
 

Forresthyd

New Member
Joined
Mar 10, 2021
Messages
3
Location
Scotland
How did you make out with this project?


So, its taken a while due to the machine always being busy.

But got a chance to finally fit a 6way diverter valve into the system,
P1 > A = charge pressure as normal
P1 > B = pressure bypassed straight to return ensuring travel pumps are de-energised.

And the second side is plumbed into brake system, just T'eed into existing circuit for OEM mechanical valve.
P2 > C is brakes pressurised off by moving OEM mechanical valve.
P2 > D is Brakes pressurised off by activation of electric diverter valve.

The valve is wired up to rear mounted "deadman" handle, there is an additional switch in cab to enable inside or outside control of system, when left on "inside" everything works as normal, when clicked to outside it then requires operator to grip deadman to move machine. By gripping the switch it allows pressure to flow through travel pumps and releases brakes.

I have also wired up an emergency stop switch from the handle to the fuel shutoff solenoid to enable engine stop in event of and emergency.

But, even after all of this. It has a small issue that is bugging me.
95% of the time the deadman handle upon release, activates the brakes immediately. But there is instances where the machine will continue to move for approx 1 metre.

Any ideas how or why?! Anyone? Because I'm stumped, my only thought is due to back pressure in the return line restricting the free flow for the brake disengagement
 

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lantraxco

Senior Member
Joined
Jan 1, 2009
Messages
7,704
Location
Elsewhen
So, its taken a while due to the machine always being busy.

But got a chance to finally fit a 6way diverter valve into the system,
P1 > A = charge pressure as normal
P1 > B = pressure bypassed straight to return ensuring travel pumps are de-energised.

And the second side is plumbed into brake system, just T'eed into existing circuit for OEM mechanical valve.
P2 > C is brakes pressurised off by moving OEM mechanical valve.
P2 > D is Brakes pressurised off by activation of electric diverter valve.

The valve is wired up to rear mounted "deadman" handle, there is an additional switch in cab to enable inside or outside control of system, when left on "inside" everything works as normal, when clicked to outside it then requires operator to grip deadman to move machine. By gripping the switch it allows pressure to flow through travel pumps and releases brakes.

I have also wired up an emergency stop switch from the handle to the fuel shutoff solenoid to enable engine stop in event of and emergency.

But, even after all of this. It has a small issue that is bugging me.
95% of the time the deadman handle upon release, activates the brakes immediately. But there is instances where the machine will continue to move for approx 1 metre.

Any ideas how or why?! Anyone? Because I'm stumped, my only thought is due to back pressure in the return line restricting the free flow for the brake disengagement
Is your brake solenoid valve in series with the mechanical brake valve?
 
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