New brakes barely working

[LyleB]

Well, I got the trailer back with the new axle on. Went and picked it up, but driving home, could not get any perceivable braking action from the new brakes. Adjusted the gain and sync to their max settings, but still no noticeable braking when the manual lever was activated.

Took the trailer back to the installer, they said they could hear the brakes activating, tried using the manual lever with absolutely minimal braking felt. Pulled the trailer back into the shop, jacked it up and adjusted the brakes. Could get one wheel to stop when spinning it by hand, but the other, while getting more difficult to spin, could still be turned by hand when the brake was applied full force.

They then decided to re-do the electrical connection to the least functioning brake, with no improvement. Said that sometimes they just needed to be worn in, so want me to drive it around for a while and see if they improve. This sounds very odd, but I see in reading some online forums that this is not entirely out of the realm of what others have been told.

I don't have any trips planned for a while, so I guess I'll just be towing it around for a couple hundred miles to see if they get any better. Let's just say that I'm very skeptical at this point.

Imagine the carnage if your car brakes had to be "worn in" for several hundred miles before they started working again after being serviced.

[Byron Kinnaman]

Scamp 13' brakes are very small 7.25" drums. There's not a lot of braking action. I leave mine on max and figure the main job of those little brakes is keep the trailer behind the tow. A couple of incidents have proved that to be true and my trailer is here and healthy because of the brakes.

[Jack L]

Until the brakes "wear in" only the outside ends of the shoes make contact with the brake drums. After the wear in, the entire shoe makes contact with the drum.

[Carl V]

My popup has 7in drum brakes. As mentioned, they are not very powerful brakes, and I was never able to lock the wheels even at full gain. This is normal for these brakes.

They do need a bit of break-in when new. I replaced the shoes on mine a couple years ago and initially I couldn't feel much braking action. This improved noticeably after a short while. Still never enough to lock the wheels (not my goal anyway) but I definitely feel the braking action back there.

Now my FG trailer has much larger brakes (10"?) and boy can these grab hard if I want them to. World of difference.

[Dan Meyer]

It sounds like you have already covered the possible mechanical problems. At this point I would double-check all electrical connections and measure the voltage at each magnet with the manual lever fully applied. If you don't have 12 volts, I'd start looking for a bad connection in the wiring somewhere on the trailer or tow vehicle. Do all of the lights in the trailer work properly? If not, fix the electrical problems and your brake will probably work properly also.

--Dan Meyer

[LyleB]

Ok, thanks everyone. I feel a bit better hearing your experiences.

Guess I heard so much about getting a progressive brake controller in order to avoid the jarring and jerking of a conventional controller, I was expecting to feel more effect when gain and sync were at their max. I can barely feel or perceive the braking when driving at 40 MPH and applying the trailer brakes.

I'll give them some time, and lower my expectations.

A good thing is that they contacted Scamp Service who gave them the tips they needed for installing the new axle as a bolt-on. They had to fabricate two, asymmetrical mounting brackets and reinforce the frame at the mount point. Scamp did tell them that my frame was the heavy gauge steel, so would not need any reinforcing at the bend to the A-frame tongue. That was something I had asked them to check.

[LyleB]

Yes Dan, all the lights are working properly inside and out. I had those corrected last fall when two of the lights would not light. At that time, the shop found several grounding issues that they corrected.

I'll give it some time. The installers told me if the brakes don't improve, to bring it back and they would check it out further. They did check the voltage at the plug, since this was a new controller that a different shop had installed a while back. I had never used the controller on any other trailers, so that is another possible area of fault as well.

[Darwin Maring]

Each year I have to apply the brakes and burn off the rust on the drums B 4 they start to work good.

[Darral T.]

I pull a 13' with a Nissan Frontier and I do my final CHECK before leaving the driveway by applying the lever on my Tekonsha Prodigy. It will "jerk" my truck.

I dont agree that you should still be able to turn the NEW brakes by hand when fully applied! Is this a "Dexter", "Lippert" axle? If so, I would give THEM a call.

You said they adjusted the brakes again.....are you SURE they're running them out enough? It takes quite a bit of cranking to get the shoes out. In my opinion, they still should be adjusted out towards the drum.

For what it's worth, when my Scamp was brand new, I could feel it tug when I applied the full 12v from my brake controller's lever. I realize that you have to break in the new shoes. But IF that little of the shoes are touching the drum, it sounds to me like something could be wrong inside.

Here's one food for thought... you may hear a "scraping" when you free-spin the wheels by hand. DONT be fooled into thinking this is necessarily the brake shoes. It's more than likely the "magnet" dragging lightly and that's normal. (when the brakes are idle)

[Jack L]

You could have a weak magnet on one side. If the brake on one wheel grabs a little and the other does not grab at all and both sides are properly adjusted, I would check the magnets,

[Darral T.]

You bring a good point Jack. The big question there is "IF" both sides are adjusted properly...

I learned from Dexter's docs on how to adjust their brakes: Run the brake shoes out until it "locks" the wheel and you cant or barely can spin the wheel. Then back it off until- Dexter says: "You feel the shoes slightly dragging." But you HAVE to make sure the shoes are releasing properly!

Dexter also describes on how to "seat" the shoes. They say drive 40 mph and apply the trailer brakes 20-30 times slowing to 20 mph each time. They recommend letting the brakes cool between applications.

Originally Posted by Jack L

You could have a weak magnet on one side. If the brake on one wheel grabs a little and the other does not grab at all and both sides are properly adjusted, I would check the magnets,

[LyleB]

It's a Lippert Axle, purchased through Scamp. The passenger side will lock up when spinning the wheel by hand, the driver side will tighten when full electrical power is applied, but you can still turn the wheel by hand with effort.

I'll put some miles on it the way it is, but yeah, I can't believe that they are supposed to be this weak.

The guy who adjusted them told me he didn't want to adjust them any further out, but if they don't get better, I'll pass this info on to him about Dexter's suggestion of adjusting them out until they lock up, then backing off some.

I have time before any long trips are planned, so I'm not in a crunch situation. Plus, my TV is a F150, so it has plenty of stopping power for this small of trailer. Mostly wanted the added security when I head out west to the mountains and for Freeway driving, in case I ever experience a sway problem - I like the idea of having a decent option to counter it.

Thanks for your replies, I'll save this info for future use in trying to rectify the problem.

[Darral T.]

Lyle, I went back and looked at my own documentation from last year when I adjusted my brakes for the first time. I realize now, I should have adjusted them after the first 200 miles as Dexter recommends. I caught my brakes not being equally adjusted after I took my Scamp out for a spring "test-run" to check the hub temps...a WHOLE 'nuther story!! To make a long story short, I discovered the curb-side brakes were doing most of the work. I adjusted my road-side (driver's side if you're in the tow) and it took over 20 LEVER movements to lock that wheel! That's ALOT. That's how far out of adjustment it was. That is why I'm recommending somebody run it in until it locks the wheel! Then back it off.

As a post-adjustment comment, I did have back off considerably as the brakes kept appearing to "drag" after applying the brakes. Mine and Dexter's thinking was they probably needed cleaning inside. That shouldnt be an issue with yours.

Good luck...but I dont think you'll have any luck until somebody does the "lock" method. But that's just my opinion. One word of caution, if you get them adjusted....make SURE you test drive your Scamp and keep a watch on the hub temps. After adjusting mine and figuring out they were sticking, my hub (driver's side) shot up over 35 deg F MORE than it ever had!

Oh boy...these RV's can be a trip. The biggest maintenance aggravation I have are the brakes/bearings.

[LyleB]

Darral,

After reading your earlier post, I downloaded the Lippert axle manual (which includes the brake info). They basically have the same recommendations as Dexter. 40 MPH, Apply trailer brakes only until you are at 20-25 MPH, drive a mile to let the brakes cool, then repeat. Do this 40 to 50 times. They say to do this prior to adjusting the brakes.

After the seat in, adjust the brakes if necessary. Their instructions were also to adjust until it's impossible, or barely possible to spin the wheel, then back off until just very slight drag from the pads.

They state these procedures should solve most initial problems.

So I will just drive around a bit, next time I take it out I will try to do the 40 MPH procedure. Then take it back to the shop and take a copy of the manual that explains how to adjust them with me for the tech to look at.

I'm starting to see why so many folks resort to doing their own regular maintenance, besides saving money, you have to know what SHOULD be done in order to make sure the service folks are following through properly.

The manual also has a troubleshooting chart if the brakes are still misbehaving. :-)

Again, thanks everyone for your tips and suggestions.

[Darwin Maring]

Check the Ground wire on each side to make sure you have a good ground.
Check the Hot wire on each side to make sure you have adequate power.

[Mike Magee]

On two occasions, with two different trailers, I have encountered the issue of little braking action with new shoes. They really do have to wear in. After some use, they worked fine for a long time.

[Wayne Collins]

Looks like a lot of "experience" out there.

On the electric side, do you have a hard wired ground from each brake back through to the TV? Do not rely on frame ground through the hitch ball.

When breaking in new brakes, be careful to not let them get too hot. Overheating will cause them to glaze and lose grip.
Drive at a moderate speed - away from traffic.
Apply trailer brakes hard, then release, a few times with a few minutes between for cooling. This is called burnishing.
It wears off the high spots so the entire surface of shoes makes contact with the drums. Then readjust for proper clearance.
I wonder if somehow you have one with the brake installed backwards. In the forward direction drum brakes will self energize. In reverse they don't.
Try that weak one in reverse... ???

[obieturner]

Originally Posted by Jack L

Until the brakes "wear in" only the outside ends of the shoes make contact with the brake drums. After the wear in, the entire shoe makes contact with the drum.

In doing truck brakes, the brake shoes are ground by the installer to match or be a slightly shorter radius than the drums.

[Jack L]

Originally Posted by obieturner

In doing truck brakes, the brake shoes are ground by the installer to match or be a slightly shorter radius than the drums.

I remember doing this to automobile brakes in the 60's. We had a special machine just for this purpose. I have not seen this done in any auto shop in many years. It makes perfect sense because until the shoes make full contact with the drum, braking is reduced substantially. I was told that the reason this practice was not used much anymore was because of environmental concerns regarding brake dust. Interesting to see that this is still done in truck shops.

[Keaner]

Originally Posted by Darral T.

You bring a good point Jack. The big question there is "IF" both sides are adjusted properly...

I learned from Dexter's docs on how to adjust their brakes: Run the brake shoes out until it "locks" the wheel and you cant or barely can spin the wheel. Then back it off until- Dexter says: "You feel the shoes slightly dragging." But you HAVE to make sure the shoes are releasing properly!

Dexter also describes on how to "seat" the shoes. They say drive 40 mph and apply the trailer brakes 20-30 times slowing to 20 mph each time. They recommend letting the brakes cool between applications.

Good info. I never thought to run them in before adjusting them. here is a link to the dexter axle brake adjustments.

http://www.dexteraxle.com/i/u/614960...ric_Brakes.pdf