Trailer Brake Question

[dabassking]

2008 Triton dual axle trailer with pads/rotors on the back axle. I just got home from the lake, about 70 miles one way. When I got home, the rear wheels were covered in brake dust and the hubs were hot. Not smoking hot, but too hot to comfortably hold your hand on. I just bought this boat and this was only my 3rd time having it out. I thought I heard some light “roaring” when towing today but it wasn’t really loud and I wasn’t quite sure if it was normal and I was just noticing it now since it’s new to me. It towed fine. It never felt like the brakes locked up or anything.

Some additional info that may be relevant is that when I went to look at the boat at the dealer, there were extra brake pads in one compartment and the master cylinder in the tongue was dry. The dealer filled it full with brake fluid for me and I went on my way. A 7 hour drive home from the dealer didn’t show any sign of brake problems. Now today when I opened the brake cylinder, it wasn’t dry but wasn’t even close to full like it was at the dealer. When I dipped my pinky into the fill hole, the fluid only went halfway up my pinky nail.

With all that info, could someone give me a few ideas on what to check? I’m thinking maybe I need to bleed the brake lines and put more fluid in.

In the meantime, I’m about to jack the trailer up and see how bad the pads are sticking.

[fishnfireman]

Were the extra pads new or used ?
The reservoir doesn't hold very much to start with so as the pads wear it won't take long to drop the level.. Also when the calipers are compressed to install new pads. The level will need to be rechecked after a good trip

[1BADAIR]

If it was dry did te dealer bleed the brakes?

[dabassking]

Were the extra pads new or used ?
The reservoir doesn't hold very much to start with so as the pads wear it won't take long to drop the level.. Also when the calipers are compressed to install new pads. The level will need to be rechecked after a good trip

The extra pads were new.

[dabassking]

If it was dry did te dealer bleed the brakes?

They did not.

[hooken203]

I have been down this road so many times with my boat trailers. Working on mine right now. I would add to the master cylinder until it right at the bottom of the rubber seal. Put the cap on. Hook up your trailer do not hook up the lights. Now try to back up. If your brakes are working right you won’t be able to back up. I would bet you will be able to back up like you have no brakes. Because you don’t. Bleeding the system will be needed and its a pain in the butt. If your brakes are working and to answer you question there is a little metal tab up under the coupler. Make sure that tab is pushed up if you hear something click or snap then that’s what your problem is for today.
If you have to bleed them I can tell you right now it will be money well spent to buy a brake bleeder that is made for bleed trailer brakes. It works so well and saves a ton of time.

[dabassking]

I have been down this road so many times with my boat trailers. Working on mine right now. I would add to the master cylinder until it right at the bottom of the rubber seal. Put the cap on. Hook up your trailer do not hook up the lights. Now try to back up. If your brakes are working right you won’t be able to back up. I would bet you will be able to back up like you have no brakes. Because you don’t. Bleeding the system will be needed and its a pain in the butt. If your brakes are working and to answer you question there is a little metal tab up under the coupler. Make sure that tab is pushed up if you hear something click or snap then that’s what your problem is for today.
If you have to bleed them I can tell you right now it will be money well spent to buy a brake bleeder that is made for bleed trailer brakes. It works so well and saves a ton of time.

The brakes definitely work. I could tell they were working on my way home from the lake. The problem is that they weren’t completely releasing and got really hot. So hot that the vault hubs threw grease out the back. I pressed that tab yesterday after doing some research and didn’t hear anything. When pressing that tab and manually pressing the master cylinder with a screwdriver through the hole behind that tab, I could see fluid swirling, which tells me that the cylinder is sending fluid when depressed and receiving fluid back in when released. I’m hoping it’s just that I need to bleed the brake system. I’ve read that air in the lines could cause the calipers to not release fully.

[Jeff Hahn]

The dealer didn't bleed the brakes? Stay far away from that dealer...idiots!

[hooken203]

I would be looking at your calipers. Air in the lines will not make the brakes stay on. I would still do what I said and see if you can back up with out the light connection hooked up. If you have air in the lines the brakes will not work. If the brakes were staying on there can be several possibilities. The caliper piston is stuck. The caliper mounting slide pins are stuck or sticking. The pads are stuck in their mounting bracket.
If the master cylinder was empty and all the dealer did was fill it up and send you on your way then you definitely have air in the lines. If the brakes were not working when the boat was traded in then you will need to find the problem as to why.

[dabassking]

I’m revisiting this thread because I’m still having issues. I took the trailer to a auto shop in town that was recommended to me by a local guy. Long story short, I was less than pleased by their work. All they did was replace pads and rotors and repacked the bearings where they had gotten so hot they spewed grease out. The mechanic told me the caliper slides were rusted and that’s why they were sticking. It’s weird that they would both rust and start sticking at the exact same time but he’s the “expert”… Anyways, the trailer did fine for 2 trips and on the third they starting sticking again and were very hot when I got home.

I’ve done a bit more research and my master cylinder may not be working properly in that the brake fluid is not returning back into the cylinder after the breaks are released. I’ve attached a link to a video of the inside of the master cylinder while I manually work the brake piston in the tongue. From what I’ve read, you should see the fluid swirl as it returns from the lines but I don’t see anything going on. Could someone more knowledgeable than me watch the video and tell me whether or not this is normal?

https://vimeo.com/606010755

[fishnfireman]

If my boat was here I would check it out. What they say about the fluid swirl sounds right..
I had a brake line get pinched and it caused the condition you describe --

[Blair B]

As rusty and nasty as that actuator looks, I would replace it. If you have an air compressor, I would buy a pneumatic bleeder kit from Harbor Freight for $31.99 and purge the system of all the old fluid in the lines. I can run a 32oz. Bootle through my brake system in about 15 minutes. I would also check the pistons in the calipers and make sure they slide smoothly, and replace if they don’t, or if the calipers look like the actuator. I would check Eastern Marine, Pacific Trailers, Shadow Trailers, Champion Trailers, Redneck Trailer Supplies, and Amazon.

[dabassking]

If my boat was here I would check it out. What they say about the fluid swirl sounds right..
I had a brake line get pinched and it caused the condition you describe --

I checked all the brake lines last night. Everything looked ok. The only soft lines are running from the actuator to the hard line that runs inside the trailer frame, then another soft line running from the hard line coming out of the trailer to the first caliper, then it’s another hard line running from there to the next caliper. All that is to say that I don’t think it’s a kinked line unless the hard line inside the trailer frame got kinked somehow, but I don’t know how that’s possible.

[dabassking]

As rusty and nasty as that actuator looks, I would replace it. If you have an air compressor, I would buy a pneumatic bleeder kit from Harbor Freight for $31.99 and purge the system of all the old fluid in the lines. I can run a 32oz. Bootle through my brake system in about 15 minutes. I would also check the pistons in the calipers and make sure they slide smoothly, and replace if they don’t, or if the calipers look like the actuator. I would check Eastern Marine, Pacific Trailers, Shadow Trailers, Champion Trailers, Redneck Trailer Supplies, and Amazon.

It’s definitely rusty and should probably be replaced, even if just for preventative maintenance (if it’s not the cause of my current problem). No air compressor so I’ll be bleeding them manually, unfortunately. Also, according to the mechanic who replaced the pads and rotors, the caliper pistons themselves were ok and were not the problem. I should probably still check them myself to be sure. Thanks for the input!

[fishnfireman]

It’s definitely rusty and should probably be replaced, even if just for preventative maintenance (if it’s not the cause of my current problem). No air compressor so I’ll be bleeding them manually, unfortunately. Also, according to the mechanic who replaced the pads and rotors, the caliper pistons themselves were ok and were not the problem. I should probably still check them myself to be sure. Thanks for the input!

That sounds like your best option.

[Blair B]

You can also buy just the Master Cylinders for a lot of them. I’m not sure if yours is an A-60 or not. If it is you just need to order it for disk brakes and whether you have 1 brake axle or 2 brake axles.

[Blair B]

If can borrow an air compressor from a friend or rent one, it will save you a ton of time and headache, using the pneumatic brake bleeder. It make bleeding your brakes a one man job.

[Lightning 6]

Marine Master Website has some good troubleshooting information.

https://www.marinemastertrailers.com/documentation/

[mikesxpress]

I learned along time ago that these surge brake actuators are "consumeable" items best replaced than repaired especially after 5+ years of use. Once rust forms inside the master cylinder it's almost impossible to fully get it out. Flushing just pushes it to the calipers and now you have more issues.

[javelin90]

I would also check the brake caliper also. If the calipers are sticking they can stick and not released I have all 4 calipers off, remove caliper check for wear on piston outer wall and wear inside the caliper system. If you continue to loose fluid and rust inside actuator. Replace the assembly as it is cheaper. I got my complete ufp 60a actuator from shadow boat trailer. Also check for leaks at the brake hose from trailer to the caliper brake/crush washer. Depending on how muchkvement the person installing pads could has caused a leak. Bleedimg brakes is not that hard. Take your time.