zz28zz

After more thought, welding the mechanism would likely prevent the breakaway lever from reaching the locked position, so that's out.
Found parts breakdown on Myco site that shows the master cyl spring mechanism. I see different options for the master cyl between drum and disc but only appears to be one spring mechanism available. Thinking i need more spring tension..Maybe the springs lost tension over time?? They are a bit rusty..

zz28zz

Stopped by the local trailer dealer yesterday and they had the spring mechanisms for the master cyl. Sales guy said he never sold a set in the 3 years he's been there. The dusty price tag said $23/ea but he had to raise it a little since it was an old price. They are $40/ea now.

Got the left and right sides for ~$60. Tried to come up with a way to measure the spring tension on the bench but wasn't successful. These things are STIFF. The new ones look almost identical but did notice the springs are compressed slightly more (~1/4 in) on the new ones.

Installed them last night and noticed the breakaway lever is noticeably stiffer. Went for a test drive today. Did the same routine along the same path as prev. Ambient temp also the same.
All the truck brake rotors again at 250-260 degs F. Trailer brakes now 220 degs on both sides. Not as hot as I hoped for but a definite improvement.
Braking feels much better. I can feel the rear of my truck squat a little now during heavy braking (which it didn't before) and truck isn't being pushed nearly as much.

Before the test drive I placed a short piece of vac hose over one of the protruding rods the master cyl slides on to indicate if the spring assy were actually being compressed during heavy braking. They are..

Not EOH, but I still consider this repair well worth the investment. BTW, my coupler/actuator is a Titan 10.

FWIW, Myco recommends replacing them every 10 years. They also sale new master cyls with the spring mechanisms already installed (they refer to them simply as "brackets")..

liberator221

Good info. Never would have guessed.

zz28zz

Me either. It may just be a Myco thing.

fossil fuel

Surge brake systems are awesome for a u haul trailer. With the development of modern EOH systems why even consider a 50 year old system that will forever plagued with the same issues? Time after time the same stuff? Switch over to EOH and your life will be lots better.......Easy backing up, Braking while backing down a ramp (not sliding), no sticking, no surge slam ect ect....Just sayin

Tractionless

I have none of those issues with my surge brakes, then again I have much more diving experience than most.