On Tue, 19 Jul 2005 10:18:07 -0400, "Gene Kearns"
wrote:

On Mon, 18 Jul 2005 23:16:02 -0700, "Mr Wizzard"
wrote:


Can you explain this to me? ...Or explain your thoery on
why not releasing surge brakes caused all this apparatus
to fail ? (I don't know jack about surge brakes), but it
would seem to me that if you tried to back up a trailer
with brakes on that it would be hop, skip, and jumping
all around the place, and generally lettung you know that
the brakes are on.

Basically, you are correct... bottom line is, you have to give a sh*t.
Every time I have observed this problem has been soon after
maintenance or yard related moves. If you have a big enough tow
vehicle, you can muscle around even the largest trailers and that
bends backing plates. strains brake pads, and torques the axles and
springs....

FYI, a surge brake system doesn't know the difference between wishing
to stop or slow down the trailer and backing a trailer up.... it only
senses pressure and applies the brakes if the tow vehicle and trailer
push against each other. In that sense, there is a solenoid that
actuates when the back-up lights are energized on the tow vehicle that
prevents hydraulic pressure from the brake cylinder to pass on to the
wheel cylinders and the trailer freewheels backwards. If the tow
vehicle operator doesn't have a way of energizing this solenoid, the
inevitable result is backing the trailer against the brakes.... and
the harder it is to back the trailer and the larger the tow vehicle,
the more likely the damage....


Also, I lost track of how any of this
was caused by water etc. (something about the solenoids?)


The solenoid is electrically actuated from the tow vehicle back-up
lights. Depending on the wiring harness, it may or may not be possible
to disconnect the lights (during immersion) without disconnecting the
wire to the back-up solenoid.... and, thus, forcing the operator to
back-up against the brake pressure.

These surge brakes must be different on bigger trailers. Every surge
brake that I have ever seen on smaller (3,000 to 5,000 lb boats) boat
trailers are free wheeling in reverse specifically for that reason (of
course these were all drum brakes, if that makes any difference).

The Other Dave Hall