Midway through my shift yesterday I noticed that the red emergency air line was blowing, on closer inspection I found it was leaking from the end that connects to the cab, I called the office and reported the defect and after some discussion made the judgement that I could get back to base OK - which I did with no problems but this has got me wondering what effects a leaking or bad trailer connections could have… can anyone give me a run through on the effects that a bad connection (air and electrical) will have for each of the five trailer connections and the best course of action to take for each scenario.
I have noticed that the airlines do not always form a perfect seal with the trailer at the connection point but lubricating them with a bit of spit seems to do the job and previously I have lost the lights down one side of the trailer, which came back on once I had reseated the connection.
Air lines and electrics can be a source of hassle. It’s not uncommon to get a “whisper” from an air line or for an electric line to have to be plugged in twice before everything works. Having said that, it’s not frequent - just not a huge surprise as and when it happens. It can often be cured by giving the whole connection a wiggle. A squirt with WD40 often shifts the bit of muck that’s probably causing it.
A serious loss of air will lead to the trailer brakes coming on. This will always be on a dark evening, around 5.30 in the middle of a box junction in a city centre. Oh, and don’t forget the rain.
Clearly, any electrical lead problem will result in lights not working.
I’m not going into any more depth. I think that’s enough for a driver to know - served me well for over 40 years and I’m no mechanic!
The airlines connect with taper seals, inside which there are little rubber ‘O’ rings to help with the seal. These can tear or get nicked over time which is often the cause of a poor connection. Twisting and turning the connector can sometimes reduce the leak, spit or WD40 can also sometimes help, but if the ‘O’ ring is too badly damaged it’ll need replacing. As has been said, a serious enough leak on the emergency line will force the trailer brakes on.
Poor connections on the ABS line will, of course, cause the ABS system to fail. This tends to bring up warning lights on the dashboard, and can sometimes be fixed by simply re-connecting it. If not, the trailer will lock up on harsh braking and you’ll get a cab full of tyre smoke if the wind is blowing your way.
Had the red line catch on the pesky curtain ratchet lever and it ripped it 3 parts off right at the connecting nut thingie(?) on the unit end.
Easy fix if you’re prepared to apply a bit of bodgers logic (something I feel is sadly missing from todays “disposable” and/or “ring for assistance” age)
1 Jump back in the cab and boil your kettle*
2 pour said boiled water into an old cup or a cut in half bottle
3 get out you’r trusty multitool/swiss army knife* and cut away the airline at the offending end and place that end into the hot water
4 cut off the bit remaining on the metal connector nut thingie (I never said I was a technical bodger)
5 now the plastic is heated up it should slip over the metal connector nut thingie and once it’s cooled will grip it like the Wife grips my bank account.
I was going to defect the airline and get it replaced once I got back to the yard but upon checking it it was as good and solid as a new one anyway so it stayed on there as long as I had the truck.
*(if you don’t have one or all these items quit now, you’re not a proper driver)
I was wondering what would happen if any of the lines failed whilst driving, so worst case scenario say one of the air lines completely separated how much time would I have to react before the brakes locked on?
Also when I first connect to a trailer I initially get ‘Trailer Brake System Fail’ (or something similar) displayed very briefly on the dash - I take it this is just because the air has not had time to build up in the trailer braking system?
No, once the air pressure drops below a point then all the brakes will engage. It will happen in a split second if you suddenly lose pressure so you won’t have time to react. Just hope no-one is tailgating you!
Radar19:
No, once the air pressure drops below a point then all the brakes will engage. It will happen in a split second if you suddenly lose pressure so you won’t have time to react. Just hope no-one is tailgating you!
Radar19:
No, once the air pressure drops below a point then all the brakes will engage. It will happen in a split second if you suddenly lose pressure so you won’t have time to react. Just hope no-one is tailgating you!
Sounds scary!!!
I had an air line detach itself from a brake chamber on a trailer once, hoofing around France for my Brother in Law back in the 90s, going for it down hill & suddenly it just started to a stop, managed to pull over before it stopped completely, luckily for me, a passing Ferrymasters stopped & helped me work out what had happened, fixed it with a simple jubilee clip.
Out of interest, if the lines broke and it puts the brakes on, is there anything which puts the brake lights on so anything following at least has some warning of what’s about to happen? All this sounds a bit drastic especially if you’re going round a corner!
I would imagine there would be no warning to anyone behind you, except the 11s you were leaving and the cloud of tyre smoke! The brake lights work off the break pedal don’t they not the chambers etc so you’ve just got to hope they stop before they hit you
trevHCS:
Out of interest, if the lines broke and it puts the brakes on, is there anything which puts the brake lights on so anything following at least has some warning of what’s about to happen? All this sounds a bit drastic especially if you’re going round a corner!
happysack:
A wee smidgen of fifth wheel grease on the coupling doesn’t go amiss.
Dip a bit of old rag into your fuel tank, a light coating with Diesel does a great job of loosening up a stubborn collar and doesn’t make anywhere near the mess a “wee smidgin” of 5th wheel grease possibly could.
Oh and don’t forget that trailers have reservoir tanks so if a line went it would most like not be an instant lock up, you’d have to be brain dead not to notice the trailer pulling your speed down, so even on the limiter you’d most likely stop without to many drivers in your vicinity “brown trousering”
happysack:
A wee smidgen of fifth wheel grease on the coupling doesn’t go amiss.
Dip a bit of old rag into your fuel tank, a light coating with Diesel does a great job of loosening up a stubborn collar and doesn’t make anywhere near the mess a “wee smidgin” of 5th wheel grease possibly could.
A small amount of grease doesn’t smell as bad as diesel. Out of interest have you ever tried dipping a rag into a modem fuel tank?
happysack:
Out of interest have you ever tried dipping a rag into a modem fuel tank?
Just wiping a bit of cotton rag on the inside of the filler cap or down into the anti-syphon gate will usually be enough, and if not, do it when you’re putting the fuel in and leave the rag scrunched/rolled up in a ■■■■ or cranny until needed.
Ok so perhaps I wasn’t specific enough for you but the rag needn’t be dripping with diesel, just a little moisture of diesel on the rag will clean the crap off the connector collar and allow it to move freely again without smelling like the inside of a caravan dwellers white transit van.
I never said cleaning the connector and collar would create a new seal, If you have a small enough leak due to a faulty seal that 5th wheel grease could possibly temporarily fix then you’d probably have got back to base without the grease anyway as most compressors would more than compensate for that small a loss, then you’d just defect it and get it replaced.
I don’t know why you think you’d long term benefit from putting that dirty black crap on your connectors, and all I can see it doing is giving you dirty black gloves.
