Need help Identifying this!

[Bussman84]

This is on my '79 MC9 it is mounted just inside the right hand side engine compartment door. It appears to be plumbed into the air compressor on the engine. I am not sure if it is an extra oiler or maybe an air line drier of sorts? Long story short there is a plastic tube inside of there that I managed to break during the removal of the holding tank. I called an area shop to try and explain what I needed ( I presummed it was an oiler do to the design and shape of the tube however the canister on the bottom was empty). And they had no clue what I was talking about, told me the compressor oil is fed from the engine and whatever this contraption is someone has added over the years. I am need to get the bus on the highway in a few weeks and need to figure out what this is and how important it is. ANY help would be greatly appriciated, Billy

[bigjohnkub]

Looks like an alcohol injection system. Used in cold climates to inject alcohol into air system to prevent freezing.

Big John

[junkman42]

Big John is right!  I have the same one mounted in the same spot on My MC7.  John L

[Bussman84]

Thanks Guys! Really appreciate the help I was really starting to scratch my head on this one. John L. I don't know your location or habits, but I will be mostly a fair weather busser. Do you think I need to do anything with this or worry about the broken tube or do you think I can just leave this empty and not look back? Thanks again Billy

[bevans6]

I'd feel easy about taking it out.  I have heard time and again that if you inject alcohol into the air system before the air dryer you can have issues with the desiccant.

Brian

[junkman42]

Billy, I live in north west Florida and range as far north as Canada!  I have no dryer and have never added alcohol to the canister in My coach.  I would think if You were planning on freezing temps on a 24 hour basis it might be  good to leave it.  Again I have no dryer!  John L

[Bussman84]

Thanks again guys. I am going to just screw the canister back on and forget about it for now again thanks for the responses I can already feel my headache letting up

Billy

[mikelutestanski]

Hello:    THe alcohol units were installed before air dryers were common.. Air dryers wre optional for mci 7s
    Regards   mike

[artvonne]

  Every winter up in Minnesota, when it gets cold (sub zero), always see lots of semis puled over with frozen air lines, and they all have dryers. They dont all have evaporators

   A friend years ago was running trucks back and forth from Fargo, one cold winter day he calls for help, has froze brake lines, can I come get him and drive somewhere to get deicer. I didnt know squat, but gave him a ride and then watched him crawl around under his truck. Can you imagine crawling under your Bus on the emergency lane of a freeway trying to remove air lines in -10F with a howling wind? BTDT, No Thanks. I would avoid that like the plague.

  Evaporators are still used in cold northern climates, they need them. But they need to go in after the dryer if you have one. If you never plan to go anywhere cold, you dont need it. I think I would put bypass valves on it and keep it plumbed in. You never know.

[papatony]

 This was put there to catch the moister in the  Air system.  It should be checked and emptied reg.  the 4106  had a line connected for draining.

[luvrbus]

Sure don't look anything like the Haldex alcohol evaporators used on today's buses and trucks they are still used today down stream from drier but not on a Bendix system.
That is a old AE 1 Bendix evaporator not a catch jar fwiw,just so you guys have the info the Bendix bulletin TCH-008-042 states they won't warranty any Bendix parts if it has signs of alcohol in the system changed their minds about how good the system worked lol kinda like they did with the DD3 brakes   

good luck