Air System Help Please

[artvonne]

Paul, the dryer is to collect the oil from the compressor also they not just for freezing weather 

good luck

  Yeah I follow that, but if your blowing the tanks down regularly, etc...would it really matter? IOW, I'm looking for someone to convince me that adding a $200 plus air drier plus all the hose connecting and wiring is going to offer me something more than something else to break. Will the brakes chambers or other brake parts last longer?

  My understanding of the drier was its primary purpose was keeping the system dry of water in freezing environments. I will likely have to have a gun pointed at my head to ever drive anywhere below 50*F.
 

[Nineforever]

Experiences I've had with air dryers are that they are nothing but a pain anything below -25 . Best idea is to crawl under your bus close the valve .The best deffence in winter operations is install a  Sniffer bottle keep that full drain your dry tank regularly . Carry wheel chucks park on the flat < dont use your parking brakes > unless  your shutting down for the night . Brake saver in the sniffer only < straight methol hydrate only in a pinch it will eat rubber orings > carry a full bottle of propane w/ tiger torch   with a piece of stove pipe to warm things up just in case .

[Joe Camper]

I disagree. Up north you need it to keep from freezing the air system down south you need to keep the moisture out.

I would never opporate any air brake vehicle without something on it to address the issue. EVER

They have a service interval of 2 yr possibly all the problems all have is with stuff that has not been serviced correctly.

On my Pete the AD7 was 179 bucks rebuilt with exchange and I never ever had a lick of trouble with them on a 2 yr cycle. Takes an hr or 2 to swap it. IMO not a big price to pay for trouble free service.

You could go with an alcohol snifter for a vehicle with very limited use but that is a bit antiquated and a PITA if you run the bus daily.

Napa has the desiccant canister for the AD2 for like 49 bucks very cheep. Lot easier than re plumbing to fit the different configuration of the newer models.

2nd biggest related failure after lack of suggested service interval and resulting from the same is the heating element. If you are freezing up the exhaust port the heat element has failed.

[Boomer]

I tend to agree with Joe.  We operated coaches that all had dryers, in a wide temp and climate range; from 0 to 120 deg F and from desert to high humidity and rain.  We never had problems, maybe the occasional purge valve sticking. But we serviced the systems as per manufacturer's specs or sooner.  There's a reason they are standard on heavy vehicles.  Only bus I ever saw without one was a MC-9 we bought from a transit district in LA that only had expello valves on it.

[Joe Camper]

Once an exhaust port is froze all additional moisture from that point accumulates in the dryer till it plugs frozen and you can no longer make air pressure.

This is arguably the most common failure up north.

[travlinman]

Just for a current cost perspective, I spent $48.88 for a rebuilt desiccant cartridge, and the kits for the purge and check valves. Pretty cheap in my book for a healthy air system. If I did not have one of these on my bus I certainly would put one on. Just my 2 cents....

TM

[Oonrahnjay]

(snip)  If I did not have one of these on my bus I certainly would put one on.

       My bus (1976) was built with a methanol bubbler and an "oil condenser".  This condenser is a canister a bit smaller than a proper air dryer.  It had a pair of wet tanks with a drain valve on each one (both completely rusted away and replaced with a modern spring brake system).  Very high on the "things on the priority list" is installing a proper ari dryer (with a more useful governor instead of the original unloader).  The bubbler is before the compressor so it has to go.

[Nineforever]

That's just been my experiences with air dryers when it drops below -25 any thing above they worked fine rather then being froze up in the arm pit of know where i close the valve keep the sniffer bottle full maybe Wrong but it works for me  i could pull over on the side of the road at -55 plus the wind chill have a snooze for a few hours jump back into the seat and pull away trailer s and all no wheels dragging. I'm no expert or mechanic just a driver since i was a kid and learned many hard lessons driving truck in extreme conditions found that most of the time what they say in the owners manual just doesn't work up here . Pa car was up here last year with one of there test vechiles , they timed there arrival just right it was minus -50 for a week ...... need i say more I'm sure fellow members from Alaska can appreciate where I'm coming from .