brakelock

Brakes WON'T Release! By now you might realise that in my younger days I was a bit of a practical joker. BELIEVE me, I used to GET as good as I gave!!!

For those who are not aware, there is a "dead man" system on modern semi trailers, so that if air is NOT supplied to the trailer, the brakes lock ON. There are 2 lines! A supply line and a CONTROL line. Back then the 2 males fittings were on the trailer and the 2 female fittings were on the prime mover/tractor. It has to be said that, over time, nobody does this any more. Usually the supply (red) line has the female on the truck and male on trailer and the control line has the opposite - for just this reason - to make it idiot proof!!!

I forget who it was, but I found one of our blokes having a feed at a roadhouse, one night! His truck was around the back, in the dark, so quick as a flash I switched the CONTROL line for the SUPPLY line! What THIS meant was that there was no air to release the trailer brakes UNLESS the handpiece was pulled on.

I went inside, had a feed with the boys, and then we decided it was time to get into it! Out we go and I started my truck and waited..... and waited..... and waited for my mate to get going! I gave him about 5 minutes, then called him on the CB.

    "What's the matter? Can't you drive that bloody big thing?"
    "Nah! I can't get the *~%$@& brakes off!"
    "You tried the Emergency release?"
    "Yair! I tried everything! *&%@^$#"

Out we get with the torches! I went right over the bloody thing EVEN SHOWING HIM the airlines were coupled, but NOT that they were swapped. After 15 minutes, he was still baffle. So, too, supposedly was I!

I suggested that he should let me have a go at it. Maybe he was operating something wrong. I got into his truck (making sure I CLOSED the door so he couldn't see) then applied the handpiece! Naturally, air flowed to the trailer, releasing the brakes! I drove forward about 15 foot, stopped, let the handpiece go (returning it to the UNAPPLIED position), got out of the truck and said, "nothing wrong here!"

Of course, when HE got back behind the wheel, it wouldn't release again! You know, I kept this charade going for about 3/4 of an hour before the light dawned on him! I STILL get abuse about that one!

Copyright © Ian (Indy) Rosser
Po Box 140
Griffith NSW 2680
Australia
8th August 1998
(Updated 20th August 2023