Just picked up a brand new truck and the red air line is near impossible to get on, anyone know why this might be? Never had any issues with putting on airlines before but this one is different somehow.
Don’t know if you’ve tried it, but I have found that it can help to not have the engine running while you hook up the lines.
DJC:
Just picked up a brand new truck and the red air line is near impossible to get on, anyone know why this might be? Never had any issues with putting on airlines before but this one is different somehow.
I’ve found this with certain units. I’m no mechanic but if I’m struggling I just pump the footbrake for a bit & that tends to do the trick.
The seal in the female “c” union has gone hard.Spray some white grease up it or dip it in the fuel tank.
Usually new trucks have the black all in one union and self sealing valve as one unit.
Probably been sat in some storage yard for 12 months and the seal ring has perished.
best way is to change the female union and sealing unit as the one piece units are cheap rubbish.
This is getting silly now, red airlines on some trailers require the driver to push on really hard, even if you get to the point that air is ■■■■■■■ out keep pushing for all your worth and it will click on.
Putting the yellow on first can help but if your not man enough to put the red airline on you shouldnt be driving the truck until such a time that you have the muscle power to cope.
In 20+ years I have never come across this.
So as not to come across to manly, I may only have a 2 inch nail but a 16 stone hammer to ram it in with.
Dipper_Dave:
This is getting silly now, red airlines on some trailers require the driver to push on really hard, even if you get to the point that air is ■■■■■■■ out keep pushing for all your worth and it will click on.Putting the yellow on first can help but if your not man enough to put the red airline on you shouldnt be driving the truck until such a time that you have the muscle power to cope.
In 20+ years I have never come across this.
So as not to come across to manly, I may only have a 2 inch nail but a 16 stone hammer to ram it in with.
It’s not the trailer. I dropped the trailer and picked it up again with the new vehicle. First time I have ever had an airline issue, I can get it on it just seems like far more resistance than before so thought there might be a technique to it, I think it makes sense to see if there’s anything to simplify it even if it’s not the superman way.
I’ll try draining the tanks as suggested above and see if it makes it any simpler. I think it might be a different connector design as this is the only time I’ve ever experienced it.
Some lines are a bit harder than others so either lube up or man up and get ya back into it! 
On a similar line of ‘feebleness’, the day driver who shares my ‘rig’ can never be arsed to tighten the trailer curtains up properly…slack as ■■■■ front-back & rarely tightens the straps up…many are so loose, you can actually unhook them from the bed without actually undoing the buckles on them…lazy ■■■■■■■ or just puny…either way, ■■■■■■ me off having to re-do them every night
Actrosman:
Some lines are a bit harder than others so either lube up or man up and get ya back into it!
A simple solution, make sure the trailer handbrake is set, drop the handbrake off on the unit, the airline should now be able to be fitted as there won’t be the pressure through the valve. BUT!!! make sure you reset the handbrake BEFORE you release the trailer handbrake Regards Kev. As usual on here abuse seems to take precedence over advice from the “professionals” who know everything.
As usual stupid advice creeps in, never leave the handbrake off the unit when coupling up.
This was in another thread the other week.
Yellow line then red.
kevmac47:
Actrosman:
Some lines are a bit harder than others so either lube up or man up and get ya back into it!A simple solution, make sure the trailer handbrake is set, drop the handbrake off on the unit, the airline should now be able to be fitted as there won’t be the pressure through the valve. BUT!!! make sure you reset the handbrake BEFORE you release the trailer handbrake Regards Kev. As usual on here abuse seems to take precedence over advice from the “professionals” who know everything.
That sounds like a disaster waiting to happen.
Visions of red air line going in and rolling into something or crushing someone.
Themoocher:
kevmac47:
Actrosman:
Some lines are a bit harder than others so either lube up or man up and get ya back into it!A simple solution, make sure the trailer handbrake is set, drop the handbrake off on the unit, the airline should now be able to be fitted as there won’t be the pressure through the valve. BUT!!! make sure you reset the handbrake BEFORE you release the trailer handbrake Regards Kev. As usual on here abuse seems to take precedence over advice from the “professionals” who know everything.
That sounds like a disaster waiting to happen.
Visions of red air line going in and rolling into something or crushing someone.
The lubeing up refers to somebody/anybody putting some kind of lubricant on the connections (unit & trailer side, both red & yellow)…you might even be amazed at how easy they slip on after adding ooooohhhh I dunno…maybe a bit of diesel around the collars! I take it the was missed. And thanks for the tip, I’ll remember not to try it, just in case I get distracted and forget summat, like the handbrake…professional indeed
kevmac47:
A simple solution, make sure the trailer handbrake is set, drop the handbrake off on the unit, the airline should now be able to be fitted as there won’t be the pressure through the valve. BUT!!! make sure you reset the handbrake BEFORE you release the trailer handbrake Regards Kev. As usual on here abuse seems to take precedence over advice from the “professionals” who know everything.
When the ■■■■ did you pass your test? Because I really think class 1 work isnt for you. Release the handbrake on the unit when connecting a trailer? Are you insane? God knows what other BS you supply as “advice”
And im not a “professional who knows everything” but I know theres no way n the world you should EVER be out of your cab with the handbrake off,never mind when connecting to a trailer.
kevmac47:
Actrosman:
Some lines are a bit harder than others so either lube up or man up and get ya back into it!A simple solution, make sure the trailer handbrake is set, drop the handbrake off on the unit, the airline should now be able to be fitted as there won’t be the pressure through the valve. BUT!!! make sure you reset the handbrake BEFORE you release the trailer handbrake Regards Kev. As usual on here abuse seems to take precedence over advice from the “professionals” who know everything.
I really hope nobody takes this advice on board!!! That has to be the most dangerous piece of advice I’ve heard given in a long time.[emoji15] [emoji15] [emoji15]
kevmac47:
A simple solution, make sure the trailer handbrake is set, drop the handbrake off on the unit, the airline should now be able to be fitted as there won’t be the pressure through the valve. BUT!!! make sure you reset the handbrake BEFORE you release the trailer handbrake Regards Kev. As usual on here abuse seems to take precedence over advice from the “professionals” who know everything.
That’s the near perfect solution to the airline not going on issue, do this and usually the airline will go on no problem.
The people saying it is dangerous/stupid etc clearly haven’t read the post properly where it says - “make sure the trailer handbrake is set” and “make sure you reset the handbrake BEFORE you release the trailer brake.”
I couldn’t even begin to count the number of times I’ve coupled up with the trailer brake on and the park brake off with no issues at all over a twenty odd year period.
(Facepalm)
Ok, the advice about leaving the unit park brake off is perfectly ok if followed carefully by someone that knows what they’re doing (I’m always reluctant to give this advice to newbies). Provided the trailer park brake is on and not released until the unit park brake is back on, it’s perfectly safe. As a back up you really want to be absolutely sure the unit is coupled (underneath with a torch) and leave the trailer landing legs touching the floor until the unit park brake is back on.
The downside is, the leaving the unit park brake off and the trailer park brake on trick is more help in getting the yellow line on as it is the unit park brake being on pressurising the yellow line which makes the yellow difficult to get on. Red line best idea is switching engine off and pumping footbrake to drop the pressure in the system.
If it’s still excdssively difficult to get on with the air pressue in the unit dropped then the coupling may be knackered.
when you have figured out how to put the red line on please come back for hints on how to wind the legs up
It’s not ideal but my usual solution is to kink the airline so that there is less psi running through it plus a spray of wd40 into the female coupling works every time.
kernan_d:
It’s not ideal but my usual solution is to kink the airline so that there is less psi running through it plus a spray of wd40 into the female coupling works every time.
That really isn’t ideal TBH and the nylon that susies are made from isn’t designed to tolerate it.
If it consequently ruptured and leaked enough air, whilst on the limiter, you’d need six new trailer tyres and one new pair of underpants.
kernan_d:
It’s not ideal but my usual solution is to kink the airline so that there is less psi running through it plus a spray of wd40 into the female coupling works every time.
Be better to pump the brake pedal to remove air from the system rather than kinking the airline and causing damage to it.