Surge brakes lock up
 

I have surge brakes on my boat trailer and they seem to lock up pretty easy when I brake. Does anyone have any ideas or sugestions? Is that normal?

Maybe the damping shock is worn out?

I'll check that and see what it looks like. How stiff should it be?

Air in the lines? Boatmate adjusted mine for me last year when I was there and mine's been fine ever since. They were locking up before.

Take the receiver hitch off the truck and hook it up to the ball to use as a lever to operate the master cylinder. It should be pretty stiff. IIRC it should take 5 sec or so to push it all the way down. Typically air in the lines makes brakes mushy, but I've seen stranger things.

If you have one brake that locks you need to look for problems on the opposite side. Sticking parts or air in the wheel cylinder.

They both lock up. I can feel them start to grab and then if I brake much more than that they will both lock up and start smoking and you don't even really have to bake hard for it to do it.

How level is the trailer?