Do i need a new air dryer?

[jimeneztrans84]

What about the air governor? Those tend to freeze up and not let air build up. Mine just did that 2 months ago due to cold weather.

[tree98]

Just curious, why would oil coming out of the compressor cause excessive moisture in the system?

(02-07-2018 )trucklogger2 Wrote:  Is it an older style dryer with a sniffer bottle? Maybe it is empty if there is one.
You can put half a bottle to a full bottle of safetybrake brand directly in air tanks also, this helps a lot. How about your purge valve? Easy enough to change.
Is your compressor discharging oil? Check when you dump moisture out of your wet
tank with pull cord or when governor stops compressor when it sneezes.
Add more in discharge line. If all this doesnt work, service dryer.

Theres a small metal ring in there look carefully...a new one is included in the kit butf the old one looks good I just leave it. Clean up oxydized metal before installing new one for a good seal.

[hhow55]

(02-07-2018 )tree98 Wrote:  I don't think there's a changeable filter on this dryer. It's a bendix AD9 If that tells you anything??

There is a desiccant cartridge inside the ad9 housing

[uncleal13]

I have an AD9.
All those bolts around the big bell housing have to come off, inside the bell is a spin on cartridge. It’s a bit of a pain in the butt.
Personally I just take off the whole unit and get a replacement rebuilt one. Under $200 around my area.
The cartridge itself is closer to $80, so for another hundred you get everything else new too.
PS.. drain all the air out of the system first.

[redbeard]

Could also be the unloader valve on the compressor. Sometimes if you tap it it will become “unstuck”.

[trucklogger2]

(02-07-2018 )tree98 Wrote:  Just curious, why would oil coming out of the compressor cause excessive moisture in the system?

It's not excessive moisture it is just a sign of worn out compressor and all the air dryers in the world won't help.. its moisture that can only be eliminated with a new or rebuilt compressor.

[Chamberpains]

The compressor pushing oil won't cause condensation to build. But is an indication that it's either starting to be completely worn out and/or something is cracked on the inside allowing oil to get inside the compression chamber. It's a really good sign to pull it apart or replace it. They are lubricated and cooled with the engine oil and sometimes the coolant. So when they completely shi#t the bed they will empty the main engine out in a hurry.

Also the AD9 air dryer was the most common air dryer on trucks for years. When I say they are fully serviceable, I mean you can buy EVERY part on them individually or just the o-ring kits. Whatever you feel is appropriate to rebuild it. It's good to buy another one so you can rebuild the last one and next winter you can just rotate them with a fresh one.

I'm curious what engine you have in that Sterling? It sounds like your bucket truck draws its fresh air from outside the engine intake system. Some engine and truck manufacturers located the fresh air inlet in a really bad spot for getting dry air. ie; under the air compressor or close to the ground instead of directly out of the engine intake. If I remember correctly the Ford Sterling was notorious for routing things poorly. If its one of the poorly mounted fresh air inlets just get proper piping and route it up into a more natural dry spot under the hood. Also make sure if its one that connects to the intake system, that those pipes are solid, tight and not split or cracked. Its not only a leak in the charged air intake system but also a place that moisture and dirt can be sucked in to not only the compressor but the intake of the engine when its not under boost pressure.

[tree98]

Well here's the latest....
I took the dryer apart and I found a bunch of goop that looks kinda like butterscotch pudding. Could this have plugged up the cartridge? What is it?
         

[Chamberpains]

Oil, water and dirt mixed in to a delightful cake topping known as bitterscotch goop. Clean it up and rebuild air dryer with a fresh cartridge and o-rings. Find out how much oil is being pushed out of the air compressor. Pull the discharge line off, start the truck and hold a piece of paper up to it. If it looks like the Blob sneezed on it then your compressor is pushing to much oil. A little bit of spatter isn't bad. They all push a little oil mist.