Hey guys whats the score with the shunt button,I’ve never used it,but I’m going to have too as the yards Im going to are getting smaller turning circles by the week.
One lad snapped his red airline but when he pushed the shunt button he just couldnt move,can you disconnect everything and push the button,do you have a limit in how long to use it due to air pressure,any info welcome as like I said seen them for years but never had to use one…cheers guys and girls.
FH12Volvo:
Hey guys whats the score with the shunt button,I’ve never used it,but I’m going to have too as the yards Im going to are getting smaller turning circles by the week.
One lad snapped his red airline but when he pushed the shunt button he just couldnt move,can you disconnect everything and push the button,do you have a limit in how long to use it due to air pressure,any info welcome as like I said seen them for years but never had to use one…cheers guys and girls.
All the shunt button does is release the brakes in much the same way as draining the air tanks to shift a trailer round the yard.
Very important if you do have to screw a trailer round in a very tight space, drop your lines after checking twice that truck handbrake is on 
Push shunt button, it keeps the suzies clean and you wont snap them off. This all depends on health and safety rules, they may not allow it and do not forget to put lines back when tipped or loaded, easy done to set off down the road when they give you the green light 
right thanks guys,so it will work for a while and not lock on half way round doing a turn,my suzies were stretched that much they were straight no coil in them,so gonna shunt button it next time.
FH12Volvo:
right thanks guys,so it will work for a while and not lock on half way round doing a turn,my suzies were stretched that much they were straight no coil in them,so gonna shunt button it next time.
If it hasn’t got an air leak, it will move around all day, once you get on the bay, might be wise to connect everything up again, at least you will have air for the suspension, important if they are running stackers in the back
I have to do this for a few drops to avoid burst lines and stretched susies, a lot of our trailers have the shunt button deactivated so i take all the lines out except the red. Some yards i go to are ridiculously small but its amazing what you can do with such a large vehicle in a small space. Not too healthy on the old tarmac and tyres right enough 
Wheel Nut:
All the shunt button does is release the brakes in much the same way as draining the air tanks to shift a trailer round the yard.
:
^^^^^^^^^^^^^^^^^^^^^^^
cough : old style trailers before 1990`s which are not fitted with spring brakes. : cough
++++++++++++++++++
newer style
is usual practice for at least one axle on a tractor unit and trailer to have the brakes held on by spring force, and to use air pressure to release them - thus providing a fail-safe should the vehicle’s air supply fail, or should there be a leak.
So therefore you need air in the trailer tanks to use shunt button 
.
The only time I’ve ever used a shunt button is when hooking up to a skelly without a pull out for the suzies with a 45’ box on, just pulled forward, swung the unit round and then put on the suzies, never thought of doing it to preserve the suzies though, it’s a good idea, see, old dogs can learn new tricks 
Sometimes the shunt (blue) button are sprung loaded , so you need someone to physically hold it in to release brakes temporarily.
This can be overcome on some types (though not advocated) by :- unscrewing the blue button handle - remove the internal compression spring - refit button handle.
not forgetting to reverse the proceedure (ie, refit spring) after manoever complete if your on your own 
Having done ro ro port work. I’ve used them often when I’ve had to shift somebody else’s trailer a few meters to get mine out. Don’t even wind the legs either, just move it with unit suspension fully up.
Don’t they pop out again a a certain speed?
trux:
Wheel Nut:
All the shunt button does is release the brakes in much the same way as draining the air tanks to shift a trailer round the yard.
:^^^^^^^^^^^^^^^^^^^^^^^
cough : old style trailers before 1990`s which are not fitted with spring brakes. : cough
++++++++++++++++++
So therefore you need air in the trailer tanks to use shunt button
Yes correct. What I meant to say it had the same result as diving under the trailer to open the brass tap, pre 1990. We got spoiled with them wire cables and a sprung valve!
But thanks for clearing that up!
as the shunter in our yard i use the shunt button all the time with empty trailers…lift the air suspension fully…hit the shunt button and away we go…it resets next time the park brake is applied.
not reccomended with loaded trailer…especially in a wet,snowy or icy yard…asking for a jacknife.
xamtex:
as the shunter in our yard i use the shunt button all the time with empty trailers…lift the air suspension fully…hit the shunt button and away we go…it resets next time the park brake is applied.
not reccomended with loaded trailer…especially in a wet,snowy or icy yard…asking for a jacknife.
It will also reset as soon as you put the suzie’s on and as for what somone earlyer put about it’s like draining the air tank’s. The shunt button wont work with no air in the trailer, nor will it work if the red line is connected
Great response guys thanks for the input,gonna have to use it,yards are getting daft turning circles are becoming the size of 10pence pieces… 
As you push the shunt button, always PAUSE, and be prepared to pull it back out if it all starts to roll away on you!
■■■■ sight easier to fit longer suzies and make sure they are free before driving off.