Troubleshooting Hydrastar Electric Over Hydraulic Actuator Not Working Brakes

Updated 05/16/2025 | Published 07/28/2022

Products Featured in This Question

Hydrastar Electric Over Hydraulic Actuator for Disc Brakes - 1,600 psi

(240)

$887.31

Powerbuilt Brake Bleeder - Master Kit

(17)

$8.00

Question:

I have a pj trailer equipped with the hydrstar hba-16. Since I bought it new I have not touched any wiring or had the brake line open. Recently Ive come to notice that no brakes will activate even with the pump pumping. No leaks, full of fluid, I had breaks a few months ago, its just been sitting for a little bit with no use. Is the internals of the pump bad? Should I attempt to bleed at pump?

asked by: Hank R

Expert Reply:

It is possible for the actuator inside the Hydrastar Electric Over Hydraulic Actuator for Disc Brakes # HBA16 to go bad. The brake fluid should be checked with a tester to determine if moisture is mixing with the brake fluid. As moisture gets into the fluid it can cause corrosion to build up inside the actuator and brake lines. This corrosion can cause the actuator to freeze up or debris to get into the lines and clog the lines or the calipers. I recommend attempting to bleed the entire system to determine if the actuator is moving any fluid. It is best to start at the furthest point and move closer throughout the process. The Powerbuilt Brake Bleeder # ALL648591 will help you do this by yourself.

expert reply by: Bud M

Jordan B.

5/11/2025

I’m having the same problem pump runs but can’t get fluid out of any of the caliper bleed screws. Was working fine now nothing. It’s full of fluid. I can get fluid to come out of bleeder on actuator just not the calipers

Jerred H.

5/15/2025

@JordanB It definitely sounds like you have a clogged or pinched line somewhere before the brake line t's off to the calipers. I recommend working your way back from the calipers toward your Hydraulic Actuator like item # HBA16. You'll want to disconnect the lines until you find one with fluid and then blow them out with an air compressor or replace them.

Jordan B.

5/16/2025

@JerredH So I found that I had fluid at all calipers my issue was the bleeders where clogged. But still don’t have brakes even with fluid coming out bleed the calipers seems that there’s no air. Is my actuator possibly not putting out enough pressure?

Jerred H.

5/16/2025

@JordanB If you're sure you have all of the air out of the lines and actuator then yes that is a definite possibility. Have you messed with the settings on your brake controller recently or could they have been changed somehow? I'd start there. The fact that your actuator is actually running most likely rules this out but it's an easy thing to check. If the settings are good then make sure that the actuator is properly grounded. The ground connection needs to be on the vehicle and not the trailer. Make sure there isn't any rust or corrosion that might be preventing a solid connection. Then you can try to test the unit by using a 12V battery to apply power directly to the actuator. Disconnect it from the tow vehicle and the breakaway system so that it's isolated from any other power source. First connect the white wire to the negative terminal on the battery and the black wire to the positive terminal. At this point the motor should NOT run - if it does then there's an internal issue and it will need to be replaced/repaired by HydraStar. If that checks out okay next leave the white wire connected to the negative terminal but connect the blue and black wires together to the positive terminal. At this point the motor should run and start to pressurize. If not then there's again something internal going on that needs to be repaired/replaced.