Electric-over-hydraulic Trailer Brakes

[porthole]

[In a thread on a completely different topic, participant conch mentioned he was] adding electric-over-hydraulic disc brakes [to his boat trailer].

Chuck--Do you have some details on what you used with the brakes? Replacing the non-functioning drum brakes on my trailer is one of the upcoming projects. I will be doing disc brake and was also considering electric-over-hydraulic.

[jimh]

Duane: I realize your inquiry was specifically to Chuck, but the topic of trailer brakes is one of interest to many and there are many people who have some experience to offer. In that vein, I will provide a few comments and also recommend some other resources to you.

Disk brakes seem to be de rigueur on trailers that will be immersed in saltwater.

Surge controllers for trailer brakes do seem to be a bit passé these days, too.

I gave some consideration to overhauling my trailer brake system several years ago when one drum brake failed. Since my boat trailer only sees saltwater about once every five years (or longer), I decided that drum brakes would suffice. The cost was also a factor. (And, as things tend to happen, we have not had the trailer in saltwater since I replaced the drum brakes.)

The cost of conversion to disk brakes and an electric brake controller was quite significantly more than just re-fitting the drum brakes. I was able to replace all the drum brakes for about $440 and kept the surge controller, while a entirely new disk brake system with electric controller would have been at least $1,200. Even if I had gone to disk brakes with a surge controller, I would have needed a new surge controller due to the increased hydraulic pressure that must be applied with disk brakes.

If I were a coastal boater and launched from the trailer into saltwater all the time, I think conversion to disk brakes would make sense. The brakes seem to be better able to be flushed with fresh water and tend to have a longer service life compared to drum brakes.

As for going to an electrically operated brake controller from a surge controller, I suspect this decision depends more on what sort of highway travel and terrain will be encountered. Surge controllers are quite simple and generally reliable devices, and they do an acceptable job of providing braking. Electrical controller may not make a big improvement, except in certain situations. It would be nice to be able to apply only the trailer brakes in some situations, like when descending a long steep grade or if the trailer begins to fish-tail. I can still recall the panic I felt on one trip. We were descending a long downhill grade when a big crosswind hit. The trailer began to sway. Of course, I over-corrected, inducing a sway to the other direction, and thus the trailer started fish-tailing. The following ten seconds were very tense. I don't know if I would have had the presence of mind to reach down and manually apply electric trailer brakes, but in retrospect having that option would have been nice.

As for disk brakes, I see that KODIAK-brand seems to be a popular choice in saltwater boating regions. I am somewhat amazed at how many tiers of product they have in their line of brakes. If you choose the best-grade components--that is, the ones said to have the most resilience to saltwater--you can really spend a lot of money on Kodiak-brand disk brakes.

Here is a link to a good discussion on trailer brakes. In the thread the links to photos are still working.

Here is a link to the somewhat-hard-to-find website of Kodiak.

Here is a link to an excellent series of photographs demonstrating installation of disk brakes in detail. The brakes used in this example are the Tie-Down Engineering brakes:

[conch]

I decided to do a total rebuild of my 1994 Owen and Sons triple axle trailer. The only remaining original part is the aluminum frame. The original configuration was surge drum brakes on two axles. Rebuilding was the way to go after pricing new triple axle trailers of 10,000-lbs-capacity.

I purchased the needed parts from SturdyBuilt Trailer Parts in Florida. and Eastern Marine in Delaware. I chose Kodiak rotors, hubs, and calipers, and choose galvanized axles by Dexter. The bigger decision was the [electric-over-hydraulic] actuator. After reading what I could about them, I chose a Dexter K71-651-00. Some smaller components of the system were Deemaxx brake lines and fittings, an Esco breakaway kit w/battery, and Ancor split loom for all wires and hoses. The 2-5/16in coupler was Titan-brand and the in-cab controller from DrawTite. New 4 leaf double eye springs w/bushings and SS hardware from SturdyBuilt.

When the parts were on-hand, this was a simple and straight forward swap. I put the trailer up on four jackstands and took it apart. Only common hand tools were necessary; I did not have any rusted or frozen fasteners. The [electric-over-hydraulic] actuator from Dexter uses only four wires. I used a four-inch-square weather-proof electrical box to house my connections for trailer lights, [electric actuator], and breakaway switch to the 7-pin trailer cable and connector.

Bleeding the brakes for six calipers was the easiest part of the job. No helper is needed, you pull out the breakaway switch,which turns on the actuator and bleed from the most distant caliper toward the front. There does not seem to be any color standard for trailer wiring to [electric-over-hydraulic] and tow coupler so I jotted a few notes. Some wiring diagrams for the 7 pin connector are facing it and some from the rear.

On the road the the six disc brakes of the trailer easily stop the truck and trailer when applied from the in-cab controller.

New bunks, carpet, fenders, pipe lights are simple. I put on new tires and added a spare. In hindsight I probably should have changed to 15-inch wheels from 14-inch wheels, if I had thought of it. I will see if there are any pictures around.
Chuck

[conch]

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[conch]

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[conch]

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[conch]

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[jimh]

Regarding color codes used in trailer-to-vehicle wiring, see

Trailer–Vehicle Connector Wiring
http://continuouswave.com/whaler/refere ... iring.html

My articles documents the color codes I found in use with vehicles made by General Motors and with a pre-made 7-conductor trailer cable and connector I obtained from a local supplier. I suspect that wire insulation color code may vary with manufacturer, and it will also vary with the pre-made cables on the market.

[jimh]

Drum brakes for trailers usually are of a design called release-on-backing. This permits a trailer to to be pushed backwards by the vehicle without creating brake action in the drum brakes. If you use disk brakes you cannot back up with a surge actuator unless there is a release solenoid, usually wired to the reverse lamp circuit of the vehicle with a five-pin connector. If a boat yard wants to move your disk-brake-and-surge-actuator trailer backwards, they usually have to clip a small battery onto the solenoid circuit to release the brake pressure.

One distinct advantage of using an electric controller with disk brakes is obtained if your trailer is stored at a facility that will move the trailer around during storage. With electric-actuated disk brakes, the yard can back up the trailer without any fuss.

[conch]

An additional advantage of electric-over-hydraulic brake actuators is trailer braking in reverse while backing down a ramp, plus the ability to back uphill. To comply in Florida I needed brakes on all axles. I wanted new components, but otherwise my trailer was fine, though I would have had to add brakes to the third axle. I sold all the equipment I removed in a few days, but not as quickly as my old Yamaha 250s and rigging which sold in two hours and were shipped to the Bahamas.--Chuck

[porthole]

I'm somewhat familiar with trailer disc brakes. I have Kodiak-brand brakes with a Carlisle actuator on my RV.

The electric-over-hydraulic actuator is a bit of a benefit in very hilly areas.

My 17 Outrage trailer has disc brakes with a surge coupler. Backing into my driveway is a chore. If I don't get out and pin the coupler, I cannot back up my steep driveway. Not all couplers come with the reverse lockout solenoid.

The picture shows where the pin would go to lock out the master cylinder. The pin just prevents the forward part from sliding in and actuating the master cylinder.

tie_down_coupler.jpg (166.69 KiB) Viewed 8624 times

I also have a fairly steep hill on the route to my ramp. I'll sometimes get excessive braking from the trailer going down that hill.

There are some people that do not care for the delay that is inherent with electric-over-hydraulic disc brakes. The pump has to spool up and build pressure before you actually feel anything. This delay is quite noticeable when you first start using electric-over-hydraulic disc brakes. There is at least one actuator on the market now that claims to have roughly one-half the startup time for brake application.

[andygere]

Electric over hydraulic seems to be more popular on large, triple axle trailers. One advantage over hydraulic systems is that the brake controller can be adjusted to reduce braking on long, gradual down hill grades, where a hydraulic system may actuate and heat up the brakes. For dual axle trailers, I don't see a big enough advantage to go with the added complexity. My state requires a separate 12V battery be mounted on the trailer to power the hydraulic pump in the event the trailer breaks away from the tow vehicle. That feature alone would discourage me, unless I really needed the adjustable control of this type of system. As far as reversing goes, most modern hydraulic actuators have a reversing solenoid installed, which redirects hydraulic pressure back into the master cylinder when in reverse, taking signal off of the reverse light circuit in the tow vehicle. Just put the tow rig in "R" and back up as usual.

In addition to the Kodiak system that Jimh added a pointer to, I can also highly recommend the UFP disc brake system that's installed on my current boat trailer. Here's a link to an article on the trailer with a lot of details on the UFP system. http://continuouswave.com/ubb/Forum1/HTML/022111.html

[porthole]

I moved my 17 Outrage around tonight. I have disc with the surge coupler and when I went down the street to do a K-turn to get back in my driveway, I almost had to get out and lock the actuator. I don't know why my top of the line LoadRite did not come with a reverse lockout, I ordered about everything else on the trailer.