Forum Discussion

Randu's avatar
Randu
Explorer
Aug 11, 2013

Disc Brake Hydraulic Actuator pump failure?

Noticed over the past few trips that brakes appeared to be getting weaker. P-3 controller showing proper voltage going to the pump. Pulled wheels and inspected all 4 calipers. Seen plenty of pad remaining and wear appears equal on all pads. Fluid level appeared just slightly down but not low. Proceeded to attempt to bleed just to rule out air as part of my troubleshooting. Used wife to trip the manual brake and controller shows 11.6 + volts and pump runs but nothing out of the bleeder. Completely remove the bleeder and get mostly gravity flow of brake fluid. I'm thinking the Carlisle HydraStar HBA-16 Actuator has a internal failure. The pitch of the actuator changes but it sounds muffled, not what it used to sound like.

Anybody have experiences with Disc Brake Hydraulic Actuator pumps?

Randu
  • Allworth's avatar
    Allworth
    Explorer II
    Aug 12, 2013
    Bleeding at the calipers (note the "S")is the ONLY way to be absolutely sure the air is all cleared. Start with the wheel farthest from the pump and bleed in order working back toward the source. It only takes one bubble to unbalance the system.
  • Cummins12V98's avatar
    Cummins12V98
    Explorer III
    Aug 11, 2013
    Randu,

    I have the same actuator on our 07.5 MS and so far has been great. It does concern me tho since our rigs are similar in age.

    No expert here but bleeding at the calipers in my opinion is the only place to bleed. I would give Carlisle a call. If you do let us know what they say.

    On a Side note you might think about a MaxBrake, you won't believe how much better the braking is. No joke you don't feel the trailer at all just normal truck braking. Zero delay.
  • AniJet's avatar
    AniJet
    Explorer
    Aug 11, 2013
    I changed one on the road. The pos ActiBrake brand the factory installed failed and I installed a Carlisle 1600 actuator. Works so much better than the original. Swap out was easy but a little messy bleeding the system at the campground (in the dirt).
  • Randu's avatar
    Randu
    Explorer
    Aug 11, 2013
    stsmark wrote:
    Did you bleed at a caliper or the pump?

    At the caliper. I can not get to the bleed on the pump the way DRV mounted it. Randu
  • Atom_Ant's avatar
    Atom_Ant
    Explorer
    Aug 11, 2013
    I had a bad one from the factory, or was at least damaged in transport. It made noise, but nothing like what it is supposed to, and I had absolutely no brakes when using the manual lever on the Ford controller.

    The Dealer spent a few days on the phone with Carlisle, and eventually replaced the servo. Took delivery, and they work perfect.

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