Troubleshooting a Dexter DX Series Electric Over Hydraulic Brake Actuator Not Building Pressure

Published 10/28/2021

Products Featured in This Question

Replacement Gaskets for Dexter DX Series Electric Over Hydraulic Brake Actuators - Qty 2

(8)

$35.69

Dexter DX Series Electric Over Hydraulic Brake Actuator for Drum Brakes - 1,000 psi

(34)

$1026.32

Dexter DX Series Electric Over Hydraulic Brake Actuator for Disc Brakes - 1,600 psi

(123)

$989.52

Question:

I am having problems with my Dexter DX series electric over hydraulic actuator. I can hear the actuator motor running, but no hydraulic pressure is developed. What is happeni9ng inside the unit and is there a rebuilt kit for this unit? I assume there are some o rings or other soft goods internal that could be replaced that may fix this problem, but not sure. This unit is too expensive to just throw away and not try to repair. Thanks for your help

asked by: Daryl R

Expert Reply:

We do have the Replacement Gaskets for Dexter DX Series Electric Over Hydraulic Brake Actuators # K71-688 if you suspect that there is some sort of leak causing your loss of pressure. If it is not a leak the manufacturer says that it could be one of two different things not allowing the pump to build pressure. Which are that it could be an issue with the control board or the proportioning valve.

The first thing you will want to check is the control board. The control board sends voltage to the proportioning valve and could be faulty. In order to test this you will need to pull the breakaway pin and see if you get any pressure. If you do then you know the control board is bad but if not, then this points to signs of a bad proportioning valve.

The proportioning valve is located deep inside the unit and will open and close based on the voltage it receives from the control board. If this valve is blocked or clogged then that could prevent the valve from closing which means you would not have any pressure. Therefore, I recommend disassembling the unit and cleaning the screen that goes to the valve as well as inspecting it for any other foreign objects.

Unfortunately, the proportioning valve and control board are not offered as replacement parts for the actuator. So if clearing the valve does not help your only option would be a full replacement for which I recommend using the Dexter DX Series Electric Over Hydraulic Brake Actuator part # K71-651 for disc brakes or part # K71-650 for drum brakes.