Air Dryer?

[JIM CHALOUPKA]

Jim, I for one love pictures keep them coming. They great for us simple minded people.

That's good to hear Elliott, it is often said " a picture is worth a thousand words", I hate to type, so that is my way out

JIM

[Denny]

Keep them coming, Jim. I can take the picture and after that I am dead in the water. Don't know how them off of the camera. Several people have explained it to me but I am lost. I need show and tell

[Jon Wehrenberg]

I'd like to supplement the caution Ben just made.

DO NOT UNDER ANY CIRCUMSTANCES GET UNDER THE BUS UNLESS IT IS PROPERLY SUPPORTED UNDER THE CHASSIS SUPPORT POINTS AS SPECIFIED BY PREVOST

Prevost shows where the support points are on their web site and your Prevost owners manual or shop manual should also show where they are. Hydraulic jacks are not fail safe supports.

A word about the suspension system....When the key is off, if the suspension system is functioning properly air is "locked" in the air bags but like all mechanical things the valves that are intended to close off the flow of air from the air bags can leak. Air bags can leak. The associated fittings can leak, and although it is rare, and air bag can suddenly, and without warning, burst. Unless supported your bus can drop, usually slowly, but occasionally very quickly. We lost one POG member because he was under a non-supported coach.

FWIW, regarding the changing of air dryer elements, I have changed mine without dumping system air pressure. If your bus has a properly functioning air system no air will escape. Dumping air in your air system, outside of the suspension will not cause the bus to drop if everything is working OK, but why take a chance? Support the coach.

[JIM CHALOUPKA]

Aside from the safety point of view the other reason to dump all the air is; now that the bus is properly supported for the cartridge change a body might as well get under it and drain the air tanks.

The only way to do that is when they are empty.




JIM

[truk4u]

Just to add to Jon's comments about air bags exploding... We were at Titusville 2 years ago at a mini rally and while visiting with everyone, we heard a loud BANG! Tuga had an air bag explode and his Newell had been sitting 2 or 3 days.

So, it does happen and I can't imagine the underwear cleanup needed if that happened while under the bus!

[scott13]

The pictures are great but now I'm wondering if I have a spin on filter like the picture or the complicated looking thing in my service manual. That one has a canister bolted on the top with the cartridge inside. The Detroit dealer in town suggested I change the whole dryer if it does not have a spin on cartridge. What do you guys think about that? I have access to a shop with a pit, that should make the job simpler shouldn't it? At least the bus can't fall down on me.

[Jon Wehrenberg]

I have had two types of dryers. The first was one with 3 or four bolts and a snap ring that allowed the cartridge to drop down, and the second was a spin on type. I'll take the spin on type any day. If yours is not it may be advantageous to swap dryers just for ease of cartridge replacement.

As to your access to a pit, I think you may have a false sense of security and I would urge you to make sure the bus is supported even if it is over a pit. I have a pit and know from experience that a lot of what we do beneath the bus often puts our body or arms or head between pinch points if the bus should come down unexpectedly. When over a pit, it you are reaching over an axle, or across a driveshaft, or are just bending over the edge of the pit to reach up on the chassis, if the bus were to drop suddenly the consquences could be bad. As a standard practice I back in my garage, raise the bus and place the supports under it. That way when I decide to go down into the pit to look at something, or do some work I won't get so involved I forget and place myself in a dangerous position.

[JIM CHALOUPKA]

I replaced mine last July and I will do it again this year. I have no idea as to how long it was before it was replaced. Liberty may have replaced it 2 years ago when I acquired the coach from them. I would have to check the records. I think though that I will just replace it annually.

It is easy & safe . Mine is located at the top front of the opening after removing the passenger side rear fender skirt and requires no under coach efforts..

As suggested elsewhere, bleed the system down first.

Scott, reference Ed's post above, yours might be the same, but I see it is a few years newer. (nice to have pit access but not necessary) The canister style is very convenient to change.
If yours is different try to change it before you exchange the whole unit, the maintenance change might not be that difficult, just different.
When you get to the task take pictures and post your contribution on the forum. If you don't know how to post pictures take them anyway and some day you will learn how to post or someone else will do it for you.


JIM

[truk4u]

The non spin on like I have, the AD-2 will cost you about 238.00 at Prevost for the rebuild. The bag of dessicant and parts come in a kit.

[Will Garner]

Jim,

Question for you. Are the pictures looking up from the floor or down onto the top of the mounting base? I just need to get oriented this morning.

Thanks