What Have I Got Here:

[Rob]

Since we're on the subject of air dryers:

I've got this air dryer on my truck and don't have an idea as to what series it is other than Bendix. It does not stop bleeding air until the air compressor kicks in to make more air. The air bleeds down from the reserve tanks, (both of them) and sets the brakes within 10 minutes when the engine is not running.

There are no leaking fittings. I've got all of those stopped.

Thanks,

Rob

[Superdog]

AD-2 ,I think.

[theakerstwo]

AD-2 ,I think.

how about a ad4 glenn

[theakerstwo]

how about a ad4 glenn

You can still get parts for that i have one on my B61 but many times it is the purge vavle hanging open and you can get a kit for it or exchange the conplete unit.but if i was going to change it out i would go th a ad9 and i was wronge that is not a ad4 probley ad2 like has been talked about.My cltch is slipping some times.. glenn

[HK Trucking]

AD1 or AD2.

The original Bendix air dryer that really worked.

Parts are still available for those, get a purge valve kit and a dessicant cartridge and she'll be good as new.

(Provided the compressor isn't putting massive amounts of oil into the air system.)

[CF686F1292]

I am 99% sure it is an AD2,we had them on our old units. Took about 1/2 hour to remove,clean,change,the cartridge,and do the prge valve. Also looks like a heating unit on it,check for proper operation on it also when apart

Edited October 17, 2007 by CF686F1292

[Rob]

AD1 or AD2.

The original Bendix air dryer that really worked.

Parts are still available for those, get a purge valve kit and a dessicant cartridge and she'll be good as new.

(Provided the compressor isn't putting massive amounts of oil into the air system.)

Thanks to everybody for answering. I've never seen one like that and did not know what to ask for. It does seem to work but the bleeding problem needs fixed. I go to move the truck after shutting it off for 15 minutes and have to wait for the air to build back up to release the brakes.

The air compressor does not appear to pass oil at all, if fact it looks rebuilt, but I don't know.

I bought all new chambers, (four type 30/30 spring brake, two type 20 for the steers) and a couple of quick release valves for the rears. If I get the dryer repaired/replaced, the brake system should be good. I'm getting anxious to start driving this beast!!

Rob

[Rob]

Thanks to everybody for answering. I've never seen one like that and did not know what to ask for. It does seem to work but the bleeding problem needs fixed. I go to move the truck after shutting it off for 15 minuets and have to wait for the air to build back up to release the brakes.

The air compressor does not appear to pass oil at all, if fact it looks rebuilt, but I don't know.

I bought all new chambers, (four type 30/30 spring brake, two type 20 for the steers) and a couple of quick release valves for the rears. If I get the dryer repaired/replaced, the brake system should be good. I'm getting anxious to start driving this beast!!

Rob

Called my favorite truck parts supplier today and ordered a new heating element, purge valve kit and an ancillary parts kit, (whatever that means) to rebuild the AD-2 dryer. As others have said, that is a good unit. I'll let you know how it goes.

Parts man tells me that the heating element corrodes inside the housing and most times to extract it, has to be destroyed. I'm going to replace it regardless due to no history and age.

Thanks again for all the help.

Rob

[Rob]

You can still get parts for that i have one on my B61 but many times it is the purge vavle hanging open and you can get a kit for it or exchange the conplete unit.but if i was going to change it out i would go th a ad9 and i was wronge that is not a ad4 probley ad2 like has been talked about.My cltch is slipping some times.. glenn

Hi Glenn, I've got a class scheduled for early next year, (tentatively) in OKC. I'll stop to chat some weekend should you have time.

Rob

[theakerstwo]

Hi Glenn, I've got a class scheduled for early next year, (tentatively) in OKC. I'll stop to chat some weekend should you have time.

Rob

I will be here Rob but call me when you get here 918 520 6581 glenn

[Rob]

AD1 or AD2.

The original Bendix air dryer that really worked.

Parts are still available for those, get a purge valve kit and a dessicant cartridge and she'll be good as new.

(Provided the compressor isn't putting massive amounts of oil into the air system.)

I took the air dryer off of the truck this evening and was pleasantly surprised how easily it came apart. The heater has continuity, but the "klaxon" switch is calling for heat and it is 65 degrees in the shop this evening. My preferred truck parts dealer tells me that the switch should not call for heat about 35-40 degrees. I had no problem extracting the snap ring that retained the aluminum bottom plate but got a bit of a bath when I pulled the plate from the bottom. This thing must have had a few ounces of water retained within the case. The element is saturated thoroughly and very heavy for it's physical size. I will pick up parts tomorrow now that I know that all is needed is routine service.

There is really no pitting to the inside of the shell but quite a bit of grime buildup. Absolutely no oil is in the dryer, and the discharge line from the compressor is clean. I do wonder if it would be alright to glass bead the internal area where the sealing ring resides?

I wanting to get the dryer settled before installing my new brake cans. I've got two on the rear that are rusted through on the parking brake side and you can see the coil spring inside one of them. Although I think all the rear cans are type 30/30, they are not the same manufacturer. I bought four new 30/30 spring brake chambers for the tandems, and two new type 20 for the steer axle. Also purchased two new quick release valves for the tandems.

Thanks again for the help.

Rob

[theakerstwo]

I took the air dryer off of the truck this evening and was pleasantly surprised how easily it came apart. The heater has continuity, but the "klaxon" switch is calling for heat and it is 65 degrees in the shop this evening. My preferred truck parts dealer tells me that the switch should not call for heat about 35-40 degrees. I had no problem extracting the snap ring that retained the aluminum bottom plate but got a bit of a bath when I pulled the plate from the bottom. This thing must have had a few ounces of water retained within the case. The element is saturated thoroughly and very heavy for it's physical size. I will pick up parts tomorrow now that I know that all is needed is routine service.

There is really no pitting to the inside of the shell but quite a bit of grime buildup. Absolutely no oil is in the dryer, and the discharge line from the compressor is clean. I do wonder if it would be alright to glass bead the internal area where the sealing ring resides?

I wanting to get the dryer settled before installing my new brake cans. I've got two on the rear that are rusted through on the parking brake side and you can see the coil spring inside one of them. Although I think all the rear cans are type 30/30, they are not the same manufacturer. I bought four new 30/30 spring brake chambers for the tandems, and two new type 20 for the steer axle. Also purchased two new quick release valves for the tandems.

Thanks again for the help.

Rob

Rob look and find the check valve that is between the drier and #1 wet tank and is probably on the the tank. It should be a valve that has a metal ball in it and it keeps air in the wet tank when the drier unloads or as some say sneezes.

That valve is still available and i have used the soft ball valve but it some times leaks if it carbons up. What hapens is if it is bad it drains the wet tank and that is where the governor gets its reading so if it sees low preaasure it will unload and the tank can drain down and hear we go again. glenn

[Rob]

Rob look and find the check valve that is between the drier and #1 wet tank and is probably on the the tank. It should be a valve that has a metal ball in it and it keeps air in the wet tank when the drier unloads or as some say sneezes.

That valve is still available and i have used the soft ball valve but it some times leaks if it carbons up. What hapens is if it is bad it drains the wet tank and that is where the governor gets its reading so if it sees low preaasure it will unload and the tank can drain down and hear we go again. glenn

Glenn: Great call on the ball check valve. It was not located on the tank but rather on the side of the dryer itself. It screwed into the housing and the discharge line to the tank attached to it. It was not sealing and I could readily push, or pull air through it both ways, (and I am not that much of a blowhard)!! Anyways, I got the rebuild kit, (complete), plus the purge valve rebuild kit, heater kit, check valve, and overpressure protection valve for a grand total of $94.60. I didn't think that was too bad. With all the parts, the only things reused are the main case, baseplate, and retaining ring. This rebuild should be a giant leap forward to having a reliable brake system ensuring the "Go" has some "Whoa" also.

Thanks again for the help!!

Rob

[Rob]

Rob look and find the check valve that is between the drier and #1 wet tank and is probably on the the tank. It should be a valve that has a metal ball in it and it keeps air in the wet tank when the drier unloads or as some say sneezes.

That valve is still available and i have used the soft ball valve but it some times leaks if it carbons up. What hapens is if it is bad it drains the wet tank and that is where the governor gets its reading so if it sees low preaasure it will unload and the tank can drain down and hear we go again. glenn

I glass beaded, and cleaned the inside of the shell this evening, soldered in the new heating element and switch, cleaned the check valve assembly and put it all back together. It works a lot better. The unloading is quick and does not linger any longer. The brakes also do not apply within 15 minuets with the engine shut off, (at least so far). This was a good call and advice offered here was followed to the letter. I called Bendix to see if I could get a replacement set of decals for this thing but they are obsolete of course, as is the dryer itself.

All three air tanks under the truck were bone dry. Not a spot of water came out of any of them when the drain cocks were opened. The dryer sure had a surplus of water built up inside though.

All in all, I'm very pleased with the way this turned out. I did not replace the check valve as it cleaned up very well. I'm going to retain the replacement for "just in case".

Until the next project.........

Rob