hydraulic trailer brakes seem loose

[bhollehday]

ive got a 20' tandem axle with disk hydraulic brakes actuated by the tongue. I cant seem to find solid maintenance information, is there anything outside of flushing the brake fluid?

The caliper also is completely loose. You can grab it and shake it about 1/8", the pad opposite the piston also sits loose and rattles when driving. The brakes are noisy and clunk. Could I be missing some rubber dampers, bushings, or something?

 

[alldodge]

Flushing should be good enough, but the rattling tells me the brakes are not working. Disk should have no play, so check to see if you can push fluid through using the hitch

 

[Scott Danforth]

the rust on the rotor says they are not working

 

[bhollehday]

They definitely work. The disk isnt loose its the caliper and where the pads sit. Maybe its supposed to be this way but seems odd?

These are the brakes I have:

https://trailerparts.com/tiedown-caliper-46304-fits-3500-lb-6000-lb-axles-painted-black.html

 

[bhollehday]

Here is a video:

https://www.dropbox.com/s/cb2chju16l0bj0g/Video Apr 02, 8 24 09 PM.mov?dl=0

 

[alldodge]

Guess the amount of play you will have is directly related to the amount of play there is in the pin and bore. You might be right its just the way they were made. I have tiedown disk, but don't remember that amount of play.

 

[bhollehday]

Anyone else also have experience with tie down calipers? Should I just replace them? That bushing has got to be worn, maybe I can find a replacement and press out and buy new slide bolts instead of all new calipers?

EDIT: I found this rebuild kit:

https://www.easternmarine.com/tie-do...g0j2re5csln7i0

But for an extra $40 I can get new calipers with pads...

https://www.easternmarine.com/tie-down-vented-caliper-assembly-w-pads-46304

 

[Lowlysubaruguy]

Is this 1/8” of play in and out from the rotor meaning its actual clearance between the pad and the rotor or are they moving around in the caliper. If its in and out it may be air in the system a weak master cylinder a loose wheel bearing ( can compress the calipers pistons as the rotor moves side to side under load) or the application rod needs an adjustment. its rare for a caliper to be stuck in the loose direction not that it doesn’t happen but usually they dont want to release meaning the pads are stuck tight to the rotor and wont move period. So my SWAG is the caliper may not be your issue.

If the movement is just the pad rattling around in the caliper itself the pads in the piston have little ears which are supposed to be bent or twisted to make them fit tightly in the caliper this is tricky to do until you figure out how to get just the right tension. To much tension and they bend back when installing them not enough and there loose. I generally make them not want to go on then hold moderate pressure on the pad with channel locks and tap the metal backing for the pad which ever directions needed to get them to pop or jump into place without loosing the tension you need to get them tight. This will stop your rattling if there loose. You could try brake pad adhesive but I hate it it is hard to get off if you need to service them and even harder to get the area clean enough to stick when you dont.

 

[Lowlysubaruguy]

Sorry i just watched the video. The calipers and slides are most likely fine the pads should not move on the calipers at all. Calipers need movement. It is a good idea to lube the slides with a silicone brake paste lube but there ok. The pads are your issue Bend the little ears to take up this clearance its tricky at first after you figure out where they need tweaked to obtain no movement and how to get them on the caliper without that tension going away it will be simple. See my post above.

 

[bhollehday]

Sorry i just watched the video. The calipers and slides are most likely fine the pads should not move on the calipers at all. Calipers need movement. It is a good idea to lube the slides with a silicone brake paste lube but there ok. The pads are your issue Bend the little ears to take up this clearance its tricky at first after you figure out where they need tweaked to obtain no movement and how to get them on the caliper without that tension going away it will be simple. See my post above.

How can I test the master cylinder to see if its working? You said they shouldnt be loose as there should be pressure in the master cylinder. When I took the caliper off tonight nothing came out of the brake line. Its odd though cause when I brake I can hear the brakes squeal so I feel like they were working, but maybe not.

It makes sense that there should be pressure keeping the caliper tight. But after taking the caliper off and the slide bolts, there seems to be a really bad fit, there should be clearance but it seems really odd there would be that much clearance on a brass bushing sliding a linear shaft. I order new components for $210 shipped thinking I would just replace them and then flush them, but how do I go about testing the condition of the master?

 

[alldodge]

The disc brake master cylinder releases all pressure in the lines when not being used. The pads will have an ever so slight drag on the disc. With not findinf fluid in the line, it sounds like the master was not working.

To test the master, place the ball in the trailer socket and push it in with your foot of hand

 

[bhollehday]

The disc brake master cylinder releases all pressure in the lines when not being used. The pads will have an ever so slight drag on the disc. With not findinf fluid in the line, it sounds like the master was not working.

To test the master, place the ball in the trailer socket and push it in with your foot of hand

I just looked at the trailer tongue and its sitting in the active position for the brakes completely. So if it was working and pressurized, it would have bled out when I opened the line up in the back, right? Your right, it must be bad!!??The boat has been sitting so I figured thats why they are a little rusty colored :joyous:

I suppose I could just buy a new one like this:

https://trailerparts.com/tie-down-e...n5d5y3g48lDet7EREWfIoFq-DhzZhhPhoCDeMQAvD_BwE

Instead of trying to rebuild?

 

[alldodge]

You could but that one is for DRUM brakes, you need disc.

Drum brakes have springs which after the master cylinder applies pressure to stop, the springs pull the shoes back into position and push fluid back into the master cylinder. The master cylinder has a valve in it to keep pressure between the master and the brake cylinders in the hubs

Disc brakes have no springs, so once the master cylinder applies pressure to stop, the pressure is released and the valve that is in the master has been removed or disabled. If the valve is not removed/disabled then the pressure remains keeping some pressure on the pads. This pressure burns out the pads and rotors quick

So you may actually only need a master cylinder to replace what you have, or you could replace the whole unit

 

[dingbat]

I had Tie Downs like yours on my trailer when I first got it. I got about a year out of them before the salt got to them. Pretty easy to rebuild thou.

A caliper seized one night coming home from fishing. Made to a service station at the next exit. The wheel assembly was actually glowing. The service station attendant got the hose out to cool things to work on it. Literately melted the aluminum caliper housing. Tore the brake assembly off and thru it in the back of the truck.

Installed a pair of Kodiak Disc and never looked back. The rotors take a beating from the salt induced rust on the rotors (get the ceramic pads) but the calipers have held up well. Installed new caliper pins last years after 5 seasons. Got 2-3 years on a set of pads

Highly recommend Kodiaks

 

[bhollehday]

Looks like I might have some trouble trying to rebuild.. Not sure how you would go about it with out cutting metal. If I take the pin out maybe the tongue slides out and I have access there??

 

[alldodge]

Agree, Kodiaks are far better then Tiedown

 

[bhollehday]

Well what do you know...you take the e-clips off and the pins out and everything just slides right on out !! @.@

I found all the parts for the tongue and the calipers for $340 and no more question about whats going on!!

Thanks for everyones input