m105a3 brakes dragging

[broman78]

I recently pulled an m105a3 off base. While jacking up the trailer one side of the rolled while the brake lever was down. I blocked that tire and jacked up the trailer and pulled off base. I didn't feel like the brakes were dragging when I first started driving. I drove across the train tracks and that Is when the trailer brakes started dragging. I read over the tm for a3 version of the trailer and haven't isolated the problem. If I release the brake lines of pressure should that stop the trailer from dragging?

 

[Nonotagain]

I recently pulled an m105a3 off base. While jacking up the trailer one side of the rolled while the brake lever was down. I blocked that tire and jacked up the trailer and pulled off base. I didn't feel like the brakes were dragging when I first started driving. I drove across the train tracks and that Is when the trailer brakes started dragging. I read over the tm for a3 version of the trailer and haven't isolated the problem. If I release the brake lines of pressure should that stop the trailer from dragging?

Two items cause the brakes on the A3 trailers to drag.

Check the adjustment of the brake shoes. When adjusted too tight they drag. Also my A3 has had the drums rust up a bit for lack of use and then dragged until I hit the brakes hard a couple of times.

The second issue is the rollers that the surge coupler rolls on. See if you can push the coupler in an inch or so, if not there is a good chance that the wheels are rusted to the small spindle that they roll on..

Viewing the coupler from the top, there is a hole in front of the emergency break-away cable. If you don't see an un-blocked hole the rollers need to be removed and lubricated.

You have four bolts on each side of the coupler, only remove one at a time and make reference of the "clocking" of the shaft, as this is how the adjustment is made to keep everything rolling free. The two large pins that are cotter pinned have to be removed as well as the emergency break-away parts.

 

[broman78]

thank you

 

[jesusgatos]

I thought all the A3 trailers had dual wheel-cylinders and were self-adjusting? Haven't actually taken mine apart to service the bearings and brakes yet though...

 

[wehring]

drag

when I picked up my A3 from Hooks the brakes were dragging. I disconnected the all-thread linkage directly over the axle that connects to the parking brakes. There was not enough adjustment in it to back off the parking brake.

Justin Wehring
979 997 3112

 

[Unforgiven]

The information can be found in TM 9-2330-324-14&P section 0033 00-5 which is page 163 if you have it in .pdf format.

There are two hexagonal adjusters on the backing plate. On the driver's side they are at 1 o'clock and 7 o'clock. On the passenger side they are at 11 o'clock and 5 o'clock.

They look like air breathers, but are really the adjusters for the two wheel cylinders. The M105A3's have two cylinders per wheel.

On the passenger's side turn them CLOCKWISE with a 5/8" wrench to LOOSEN.

On the driver's side turn them COUNTERCLOCKWISE with a 5/8" wrench to LOOSEN.

If the wheel still sicks & the parking brake is okay, then somebody tightened your hub spindle/bearing nut too tight.

 

[AOR]

I recently acquired an M105A3 trailer that I assume sat for many years. I towed it for about 50 miles and it made it home but when I got home the brakes smelled really hot and bad. When I went to move it again the wheel drags and locks up in my gravel lot. I am in the process of trying to remove the brake drum trying to be very carful because I do not know if I can locate another one. I backed off the adjusters on both shoes and removed all of the nuts. Using PB blaster and a brass hammer I have been trying to remove the drum without hitting it that hard.
I found the manual for it but I have not yet really found how to remove the drum I only see pictures and it is odd its hollow and uses a large wheel spacer as the brakes are inboard and surge brakes incases anyone is not familiar with the final variant of the M105. I watched the parking brakes cables while someone actuated the lever as well as attempting to free up a possibly seized cable, it made no difference the cable seems to move in and out of the sleeve without binding.

Do I need to remove the bearings and wheel adapter? I backed off both adjusters until they would no longer turn and removed the 18 nuts and washers. Am I missing something? I am afraid to hit it any harder and damage the drum. Has anyone successfully removed a brake drum from one of these? If so please share. Thank you