Ok. So a couple seasons ago, I installed new electric brakes on my myco. They work, but nothing IMO like they should. Yesterday, I was doing some fiddling around with the multi meter testing things. My controller has to be turned to the max to get any braking pretty much, and even then its marginal.

At the truck 7 pin, trailer plug unhooked, I get 13 volts with trailer brake control held down. At the trailer junction box at the tongue, with the brake wire connected, I only get 10.5 Volts. If I disconnect the wire going to the brakes, it goes back up to 13 volts. With everything connected, Im getting a total amp draw of 11.5 amps. This trailer has 4 magnets (brakes on two axles).

Now, according to this chart from Etrailer, I am within spec

10 and 12 Inch Brake Drums
Max Amps at 9-10.5 Volts
2 Brakes 5.6-6.6
4 Brakes 11.3-13.3
6 Brakes 17.0-20.0

Max Amps at 12-13 Volts
2 Brakes 7.5-8.2
4 Brakes 15.0-16.3
6 Brakes 22.6-24.5

Whats really weird though, is when I back the boat into the water with the harness plugged in, as soon as the wheels go under water, the brakes lock like a MOFO in reverse. But ONLY once they go in the water. Basically, they work like they should under water. Brakes have been adjusted properly, I have 10 gauge wire feeding them, all grounds been triple checked, and they've been this way since new. Tried different trucks and different controllers, nothing different there. Just seems like something is missing. Any ideas why the voltage would drop 2.5-3 volts from 13 to 10.5 once the brakes are connected?

you have the plates on backwards..they will stop either way going forward and backwards,,i have seen this on a dump trailer that a customer dropped off last week,,he always complained the brakes sucked and when i took the drums off the travel of the arm that the magnet attached to was facing the opposite direction..if the backing plate are,,,, right is on the left and the left is on the right then the plate arm's are limited to moving and throwing the shoes out far enough to put pressure on the drums..

BTW you have to have all the ground wire going straight to the plug and not be grounded to the trailer..

Thanks Mike. I have the ground wire directly to the plug, but it also has a terminal grounded to the trailer frame. When I installed them, I almost 100% I put the RH brake on the passenger side of truck starboard of trailer, LH on drivers side, if that makes sense. But just for the hell of it, i'll pull a drum and double check that.

In reverse, say backing up or down the ramp, you can feel them engaging, but as soon as the wheel goes under water, its like WHAM, the brakes lock like a monster. But normal backing around town, they don't lock like that.

As a matter of fact, I hooked my truck to ICDEDPPL's boat to back it in his garage. He has elec brakes too. My controller was turned up all the way (towed my boat prior), and when backing his in I tapped the brake pedal and his locked hard like mine do when submerged.

IDK, its such a simple setup, that's been giving me a headache. Im probably gonna put the boat in a slip for a week, and just redo everything from new brake assemblies, and run all new wire again, and get the never adjust assemblies this time too.

i just did a set of self adjuster ones last week,,the magnetic pucks are 1.5 times the size of the old ones..you need to run a double wire to all the backing plates..i like to solder and shrink wrap and die electric grease in the shrink tubing..14 ga tined copper wire to all and parrelle wire them and the tined double insulated wire all the wat to the tongue to a junction wire box.. http://www.ebay.com/sch/i.html?_nkw=trailer+wiring+box
then i wire in a 7 way trailer plug with the molded rubber plug..http://www.ebay.com/sch/i.html?_odkw...at=0&_from=R40

BTW b4 you install the backing plates make sure you remove the star adjuster and antiseize the threads,,they do you no good and wont adjust if their seized..they come with no lube..

Good deal. I actually have it wired just like you show. I have one of those junction boxes like you posted at the tongue. Then, I used another junction box at the rear, by the axles. The two main leads, blue from brake control, and ground, go into that box. Then, each magnet is wired into that box also. I made jumper wires to connect the terminals together like a buss bar in a way. Come to think of it, I can probably just get a couple buss bars and do it that way.

So you're saying go for the never adjust units right?

their are really called self adjust backing plates,,yes they have bigger magnets..if your drums area littls gruved i can cut them on my brake lathe..both surfaces,the shoe and the magnet surface..

the inside of the backing plate has a cable like the ford rear drum brakes that move the slack adjusters..

Just curious, if you are going to redo the whole setup again why not go with an EOH kit with disc brakes? I converted mine from surge drum to EOH disc and it was the best $1000 I have ever spent! Just trying to understand if the benefits of electric are worth staying with the setup?

Thanks
Jim

P.s. joe make sure the backing plates reas dexter...the Chinese ones look the same but dont stop for ****,,i think i pay like 49.00 per plate..

Mild- I always UNHOOK my connector befor backing into the water.Then rehookm up about 1/2 mile down the road.

Wannabe

Think I found my problem guys.

A while back I broke an axle . I got a new one from dexter. Swapped hardware over and off I went. Well, upon disassembly yesterday, I pulled the drums on that axle. Brakes were LOADED with grease. Then after further investigation, the new axle has 2.25'' seal journals. Old axles have 2.125 seal journal. So when we put the old drums on, it tore the seal, therefore pumping grease into the dam brakes. DUH!! Never thought to look at that.

So today, I am going to be replacing brake assemblies, and adding brakes to the third axle. Wiring is all new now with 10 gauge from tongue back. I think I should be in much better shape.