Both of these types of brakes require specialized experience and don’t perform well in water or freezing conditions. Surge brakes remove safety hazards in the water and with operators who aren’t familiar with other trailer brake systems.
The brakes work like normal for drivers, unless you’re backing up your trailer, and we’ll get to that later. The front side with the hitch is separate and slides on the ledge to the back half of the neck.
When the load gets heavy the rod extends between the two parts of the neck and the weight is distributed between them. Trailers with surge breaks typically start to slow when applying the brakes.
But, it’s a small price to pay for ease surge brakes give when operating your trailer. Periodic maintenance is required, but simply follow the manufacturer recommendations to get the most out of your hydraulicsurgebrakes.
Your surge brakes have got your back, but always practice increased safety when driving your trailer with a tow vehicle. Hydraulic brakes use the force or momentum of a slowing tow vehicle to apply the brakes on a trailer.
The quicker you slow down your tow vehicle, the more pressure is applied to your trailer’s brakes. However, the downside of hydraulic brakes is that you do not have independent control over the trailer brakes.
Electric brakes, though, do not apply as much force against the tow vehicle as hydraulic brakes. There will be less wear and tear on the tow vehicle with a properly set brake controller.
That’s handy when descending hills, in high winds, and when you’re being passed by large 18-wheelers. How HydraulicSurgeBrakes Work In contrast, Surgeries are hydraulic and use the trailer’s natural momentum to actuate the brakes.
When you step on the brake in your tow vehicle and slow down, the trailer pushes against the hitch and presses a hydraulic cylinder. Contact one of our 7 locations today for a free quote on your next pull behind car dolly.
The latest hardware includes controllers that are no more difficult to install than plugging them into your tow vehicle’s cigarette lighter… er … 12-volt outlet. Yes, the surge brakes stopped the trailer well enough, but when you lifted off the brake pedal to accelerate, the release could almost be described as violent.
The return spring in the master cylinder slammed the piston back out, and it really jarred the truck and its passengers. However, I think for runabouts and other boats that weigh 7,000 pounds or fewer, the simplicity of the surge -brake system is hard to beat in function or price.
Brett Becker is a freelance writer and photographer who has covered the marine industry for 15 years. In addition to covering the ski boat and runabout markets for Boats.com, he regularly writes and shoots for BoatTrader.com.
Based in Ventura, Calif., Becker holds a bachelor’s degree in journalism and a master’s in mass communication from the University of Central Florida in Orlando. Surge brakes take advantage of this force to operate the trailer brakes.
The front section with the hitch attachment is a separate piece. A master cylinder for the brakes is mounted to the back half of the neck and has a rod extending from the master cylinder to the front half of the neck.
The rod for the master cylinder can be adjusted to cause the brakes to come on sooner or later, whichever is desired. When the tow vehicle is in reverse, pushes in on the trailer neck, which would activate the surge brakes.
Inserting a pin in the neck of the trailer prevents this from happening while the driver is backing up. If the pin is left in the neck of the trailer, the surge brake will be disabled.
These troubleshooting tips assume that a person is familiar & equipped with jacking & supporting safety stands, brake tools, seal & bearing inspection techniques, shoe, drum, rotor inspections, & knows how to adjust, fill & bleed brakes. In a trailer surge brake system, the “pump” is located on the trailer-as part of the hitch assembly.
This special sliding hitch assembly is called a surge brake actuator. It has a master cylinder built into it, but instead of using your foot to operate it, it uses the weight & the momentum of the trailer to do the pumping.
Above is a rearview showing a Master Cylinder & Outlet Port (top). This heavy duty unit shows that shock absorbers on the bottom prevent the slide from jerking front to back during stop & go movements.
Here’s how it works: Picture the truck & trailer traveling down the road at say....45 mph. This compression operates the master cylinder, causing it to build brake fluid pressure.
The harder the trailer tries to push the truck, the more pressure the surge actuator builds up. The breakaway system usually consists of a cable or chain that is attached to the tow vehicle on one end, & a lever/latch assembly on the trailer surge actuator.
A latch mechanism keeps the lever in the energized mode even if the breakaway chain or cable is ripped away by the separation of the truck & trailer. The lever mechanically pushes the master cylinder piston to generate emergency brake fluid pressure & the latch assures that the pressure is maintained until the latch is disengaged manually by using tools.
Find the breakaway chain or cable & pull it until it latches in the locked position. Manually rotate the tires/wheels using your hands in the forward travel direction & see if they lock up.
Important: The surge actuator slide must be pulled & pushed (full stroke) to create pressure & bleed air from system when making repairs or tests. The slide will offer resistance due to the orifice & shock absorbers, so expect to stroke it with effort.
Rust is the enemy as it creates rough surfaces inside the wheel and master cylinder bores destroying the piston seals. We recommend you remove the brake drum & visually inspect the shoe linings.
Have them work the surge actuator from “off to on” & closely watch the wheel cylinder to see if the push rod is moving in & out. Important: the surge actuator slide must be pulled & pushed (full stroke) to create pressure & bleed air from system when making repairs or tests.
The slide will offer resistance due to the orifice and shock absorbers, so expect to stroke it with effort. DO NOT remove the orifice fitting that the hose or brake line attaches to.
This orifice is very, very small-perhaps as small as the diameter of one strand of hair on your head & can easily clog with debris. Engage the master cylinder using the lever to see if it forces a fine stream of brake fluid through the orifice fitting.
If not, remove the orifice fitting & then test it again by engaging the master cylinder. If it now pumps fluid, hold the orifice up to a strong source of light and see if you can see through it.
If not, it is clogged & is preventing the brake fluid from reaching the wheel cylinders. If the clog is on the wheel cylinder side of the orifice fitting, it creates problems when the brakes try to release because it prevents the flow of brake fluid back to the master cylinder reservoir).
(Note: it is possible for a master cylinder to pump fluid at a low pressure, but could have internal piston seal leakage that prevents it from building up adequate pressure to operate the trailer brakes.) Although you really can’t bench test the wheel cylinder, you can peel back & remove the rubber boot to look for rust or corrosion that would prove a stuck piston.
The wheels that don’t work will have one of the following problems that you’ve already learned how to test and fix: Leaking wheel seal that has brake shoes & drum soaked with grease.
Trailer surge brake manufacturers deal with this in different ways: Use an electric solenoid valve that allows the brake fluid to bypass back to the reservoir while in reverse.
The electric valve is wired to the reverse lights on the tow vehicle. Use a mechanical pin to prevent the surge actuator from compressing & building up pressure.
This pin is supposed to be used when backing up only, but if left installed can prevent the brakes from operating-even if traveling in forward. The photos should help you identify the type of brake system you have on your trailer.
Some trailer axle manufacturers can accommodate converting from one type of brake system to another without major modifications. What causes this is the brake fluid pressure cannot release & travel back to the reservoir due to a mechanical or hydraulic problem.
The clog is acting as a “check valve” allowing the fluid to come out of the fitting, but won’t let it go back in. The surge actuator slide assembly has mechanically jammed (stuck) in the compressed position & will not allow the master cylinder piston to return to it’s relaxed position-thus preventing the fluid from returning to the reservoir & releasing the brakes.
The piston in the master cylinder is stuck in the compressed position preventing the internal return spring from pushing the piston to its “parked” position-allowing brake fluid to return to the reservoir & releasing the brakes. The steel push rod that pushes the master cylinder piston is adjusted too long or is bent & will not allow the master cylinder piston to return to it’s relaxed position-thus allowing the fluid to return to the reservoir and releasing the brakes.
This kit allows you to hook up a garden hose to the brakes and flush salt water out with clean tap water extending the life of the brakes and running gear on a boat trailer. Energize the brakes while parked by pulling on the breakaway system cable or chain until it latches.
Next, place the tow vehicle in gear, and begin to slowly drive forward. You should feel the trailer brakes working & offering very stiff resistance.