CHAMPION TRAILER
PARTS SUPPLY

1-800-229-6690
FAX: 1-800-359-8169 ORDER FORM
56705 I-10 SERVICE RD SLIDELL, LA. 70458

FREE CATALOG
.PDF DOWNLOAD

HOW TO PLACE
YOUR ORDER

HYDRAULIC VERSUS ELECTRIC
TRAILER BRAKING SYSTEMS

Basic Legal Requirements

Each state in the USA, has its own laws governing trailer braking requirements. In many states, brakes are required if the trailer gross vehicle weight rating (GVWR) is 3000 # or more, and in other states it can be as low as 1000#. In tandem axle trailer applications, brakes may be required on all axles if the GVWR is above a specified weight. In Louisiana, for example, if the trailer is tandem axle, and the GVWR is 5000# or more, then brakes are required on all axles.

You should check the specific legal requirements with the Dept of Motor Vehicles in the area you expect to do your towing.

Emergency Breakaway Requirements.

Federal traffic safety law specifies that all trailers that require brakes, shall have a means of activating the trailer brakes under trailer breakaway conditions. In a hydraulic surge brake system, this is normally done by means of a cable or chain which is connected to the tow vehicle. Under trailer break away conditions, this connecting linkage is designed to provide mechanical activation of the master cylinder, and to maintain brake system operation as the trailer stops.

Emergency Brake Away KitIf the trailer has an electric brake system, the emergency breakaway regulations require that the trailer be provided with an emergency battery backup system, that will provide electrical power to the brake magnets during the trailer break away brake activation process. In an electric_breakaway system, there is a breakaway switch with a pull pin and cable which, when attached to the tow vehicle, will provide electrical activation of the trailer brakes if the trailer disconnects from the tow vehicle during highway travel. The components for this system are normally packaged as an Emergency Breakaway Kit which has battery and charger, emergency switch and battery case in one package.

Hydraulic Surge Brakes Basics

Hydraulic surge brakes are a totally trailer self-contained braking system, requiring no electrical, hydraulic or other connection of brake sensing components to the tow vehicle for automatic operation of the trailer brakes. In a hydraulic surge brake system, the inertial differential pressure developed between the tow vehicle and the trailer, during the braking process, creates a mechanical pressure which is applied to the push rod of the master cylinder in the hydraulic surge brake coupler. This mechanical pressure is proportional to the difference in pressure between the two vehicles and therefore, the hydraulic output of the brake coupler, and resulting brake operation, is automatic, regulated, and proportional to the amount of braking being applied to the tow vehicle.

Simple, effective and a proven performer on tens of thousands of trailers, this brake system has been the braking package of choice for most boat trailer owners for decades. The vast majority of boat trailer hydraulic surge brake systems are package with drum brakes, however they can be used with disc brakes with equal effectiveness. Both systems, however, have their own unique design, installation, and maintenance considerations.

Hydraulic Drum Brake Systems

Hydraulic Brake Installation
 
 

Trailer hydraulic drum brake systems can be installed on a wide variety of axle capacities.
 
 


These are the axle capacities used on most boat, utility, and RV trailer applications.

 Certain drum brake sizes are available as either

Both systems work with similar effectiveness, however, most trailers use the uniservo (single push rod) brake cluster, which are much more cost effective than the duo-servo brakes.

Hydraulic Brake  Clusters Hydraulic drum brakes are also available as either Standard or Free backing Brakes.

The hydraulic surge brake coupler does an excellent job of providing automatic proportional braking response to tow vehicle braking while towing. However, it cannot distinguish between (braking while towing) and the mechanical differential pressure created between the tow vehicle and trailer while backing up. Consequently, standard (uniservo) drum brakes, which can retain 20% or more of their braking capacity while backing up, normally require a method of deactivating the brakes while backing up. This is normally done with a reversing solenoid kit.Reversing Solinoid Kit

The reversing solenoid is activated when the backup lights on the tow vehicle come on. At this time, all hydraulic pressure in the brake system is released as any hydraulic out put from the master cylinder is dumped back to the master cylinder reservoir. When the back up light signal is removed, the solenoid is deactivated and the surge brake system reverts back to normal operation.
WARNING!! Never mechanically pin out the brake coupler!! This could lead to a non operating brake system if you forget to remove the lock out pin.

Free backing Brakes, on the other hand, automatically disengage while backing up. The reverse rotation of the wheel triggers activation of components internal to the individual brake clusters that deactivates the brakes while backing up. The brakes then re-engage for normal operation when the wheel turns forward. This is why Free Backing Brakes are normally the brakes of choice in a hydraulic drum brake system. To combat corrosion, these brake clusters are now available with hot dip galvanized backing plates, stainless steel brake springs, and can easily be fitted with a freshwater washdown kit to purge salt and dirt from the brake interior.

Click here for information on TROUBLE SHOOTING HYDRAULIC SURGE BRAKES

Hydraulic Surge Disc Brakes:

Both hydraulic drum brakes and hydraulic disc brakes, used in trailerHydraulic Disc Brakes braking systems, operate with the same principal as their standard automotive cousins. In a drum brake system, the wheel cylinder push rod, pushes out, engaging the brake shoes to the interior of the hub drum braking surface. With disc brakes, the calipers compress the brake pads onto the brake rotor surface. Both types of brakes can be activated by the hydraulic surge brake coupler as described in the hydraulic drum brake system above.

The primary difference in their operation is that hydraulic drum brakes can be manufactured with free backing components integral to the brake cluster for automatic deactivation of the brakes as the trailer backs up. Disc brakes cannot. Disc brakes require the installation of the free backing solenoid kit to deactivate the trailer brakes while backing up. In disc brake systems, it may also be necessary to remove the hydraulic return flow restrictions present in most brake couplers.

In a drum brake system, the shoe return spring pulls the wheel cylinder push rod in and the master cylinder return spring also pulls, providing a strong differential pressure, for the return of brake fluid from the wheel cylinder back to the master cylinder upon release of braking pressure from the master cylinder push rod. However, in a disc brake system, only the master cylinder return spring provides a pull return for brake fluid when the brakes are released.

For this reason, it is essential that all check valve, and other restrictions that would inhibit the return flow of fluid back to the master cylinder, be removed. If they are left in place, the brake calipers can remain locked or dragging, and may not allow the brakes to release as you attempt to pull forward.

WARNING!! It would be advisable to get written approval from the manufacturer of any brake coupler that you propose to do these mechanical alterations on. To make alterations to the interior components of the brake coupler without such approval would probably VOID any warranty or product liability responsibilities that the brake coupler manufacturer might have. It would be recommended that if you intend to install disc brakes, purchase a brake coupler designed specifically for that application.

 



PRODUCT INDEX
PLACE YOUR ORDER
TECHNICAL ASSISTANCE
CATALOG
.PDF DOWNLOAD
CATALOG
MAILED TO YOU


Electric Brakes

Electric BrakeElectric brakes are commonly used in utility and RV trailers. In this application, their painted automotive grade components provide excellent service, if properly installed, wired and maintained. In boat trailer application, however, they fare poorly. The wet launch boat trailer application, especially in salt water, normally destroys electric brakes within a season or two.

Painted automotive grade brake springs rot, adhesively bonded shoe pads become detached from their foundation plates, and water soaked magnet electrical insulation commonly fails. For this reason, most boat trailer owners opt for hydraulic surge brakes either disc or drum.

Electric brakes, as with hydraulic drum brakes, are available to fit a wide variety of axle capacities.

5 Lug Bolt Patterns:

All of the 5 lug hub drums listed above are available to fit the 1 3/8” x 1 1/16” spindle and use bearings 68149 inner (next to the seal) and 44649 outer (next to the spindle nut). In many instances, a trailer owner may change hub bolt patterns on the trailer to match the tow vehicle, so that he may use the tow vehicle spare on the trailer, deleting the need for a redundant trailer spare tire.

12" Brakes

12" hub drums fit the #42 ( 1 ¾ x 1 ¼ ") spindle and are normally available in either There are heavier versions of the 8 lug bolt pattern for 7000# and up axles.

(CAUTION) It should be noted that electric brake hub drums must have a flat machined magnet contact surface to operate successfully with electric brakes. Some hub drums are available in a hydraulic only style without this smooth machined surface. Hydraulic only style drums MUST be avoided when electric brakes are used.

Electric style drums can be used on either electric or hydraulic systems, but hydraulic style drums can only be used on hydraulic brakes.

 



PRODUCT INDEX
PLACE YOUR ORDER
TECHNICAL ASSISTANCE
CATALOG
.PDF DOWNLOAD
CATALOG
MAILED TO YOU



Electric Brake Controllers

Electronic Brake Controller Electric brakes require a brake controller to apply power to the brake system. With electric brakes, as power is applied to the electromagnets in the brake cluster, the magnets are pulled to the interior flat surface of the hub drum. As the wheel and drum turn during highway travel, this attraction of the magnet to the flat drum face pulls the lever arm of the brake actuating cam, rotating the cam and forcing the brake shoes out to contact the drum braking surface. The more power applied to the magnets the greater the leverage on the came resulting in greater braking response.

Most electric brake controllers are dash mounted allowing the driver access to the manual override button. The manual override button allows the driver to activate the trailer brakes without operating the tow vehicle braking system. This can be important if your trailer is prone to sway. By bumping the electric brakes on the trailer during sway, the driver can dampen and control sway problems should they occur.

 One negative feature of electric brakes is that if you use a dash mounted brake controller, you must have a controller on every vehicle that you tow the electric brake equipped trailer with.

As with most mechanical devices, many times the simplest system works the best.

Trailer Break Away Requirements for Electric Brakes

Electronic Brake ControllerAs previously mentioned, all trailers requiring brakes are required by D.O.T. safety regulations to be equipped with an emergency breakaway brake activation system. On trailers equipped with electric brakes, this is achieved with a breakaway switch and a trailer mounted emergency power battery. If the trailer disconnects from the tow vehicle during highway travel, the pull pin on the breakaway switch activates the trailer brake magnets providing braking power from the emergency battery as the trailer stops.

Electric brake controllers should be provided with internal reverse voltage protection to protect the controller in case the emergency breakaway switch is activated while the system is still connected to the tow vehicle brake controller. However, caution should be exercised to assure correct electrical connection of all system components. The brake controller can be damaged or destroyed by improper wiring connections.

Be sure to install an automatic reset circuit breaker in the power cable from the battery to the electric brake controller.

 



PRODUCT INDEX
PLACE YOUR ORDER
TECHNICAL ASSISTANCE
CATALOG
.PDF DOWNLOAD
CATALOG
MAILED TO YOU



 

 Trailer Brake Wiring Installation

6 Pole Connector
7 Pole Connector

Remember, each brake magnet will draw about 3 amps during full power operation, therefore:

In low voltage (12VDC) systems, voltage drop can be very notable. From the tow vehicle battery all the way back to the brake magnets can be 30’ or more of wiring. It is very important that your power wiring be large enough to compensate for the voltage drop experienced in the system. Use minimum 14 gauge wire or larger for both the (+) positive wire from the brake controller and the (-) negative wire from the magnets back to the tow vehicle.

Brake magnets should be parallel wired for optimum system performance.

PARRALELL WIRING DIAGRAM

Also never use the trailer frame or brake cluster backing plate for the (-) brake negative current return. The negative (-) wire must be brought all the way through the trailer plug back to the tow vehicle negative for optimum system performance. Loose connections at the trailer plug, wire taps, and voltage drop from wiring that is too small can radically affect your electric brake system performance. Installation tip - Never use pinch type wire taps for electric brake wiring. They may be adequate for trailer lighting systems, but the high current draw for electric brakes require compression (crimpon) connectors or soldered wire taps for best performance

TROUBLE SHOOTING ELECTRIC BRAKES

Hydraulic surge brakes are a totally trailer self contained braking system, and therefore all trouble shooting analysis can be concentrated on the trailer to resolve braking problems. However, with electric brakes, both the trailer and tow vehicle contain components integral to the overall electric brake package and therefore trouble shooting the electric brake system can be more complex.

The mechanical operation of electric brakes is fairly simple, if power is available to the magnets, and the magnets are functional. Therefore, we will assume that mechanical problems such as

will be self evident and easily identified for correction.

The majority of problems that occur with electric brakes can be traced to an electrical system problem, and we will concentrate our attention there.

A 12 VDC VOLTAGE TESTER, VOLTMETER, OR TEST LIGHT PIGTAIL WILL BE NEEDED FOR ELECTRICAL SYSTEM TEST.

 First, it is essential to isolate the problem area.

 

TROUBLE SHOOTING TRAILER SIDE