Reply
 
Thread Tools Search this Thread Display Modes
 
Old 02-14-2011, 03:11 PM   #1
3 Rivet Member
 
Join Date: Sep 2010
Posts: 159
Images: 15
EVAP Canister? question

Hello fellow Airstream enthusiasts. I am a relatively new Airstream owner having bought my former bosses 1988 Airstream 345 back in October 2010. This is my first RV of any kind and I remember when my boss bought it new. He took good care of the old girl and stored it indoors when possible only putting 44,000 miles on her in the 22 years of ownership. I had always admired it but really never dreamed he would ever sell it or that I would be able to afford it but when I decided I wanted a motorhome this is the only thing I wanted to own so I asked and it's now mine. I have been fixing little things here and there and have made a couple of short trips with it and I have been having a blast! I have been enjoying learning from searching and reading the forums but this is my first post.

I have what should be a pretty simple question for someone to answer but I have not been able to find the answer by searching the forums or Google so here goes. In the right front wheel housing in the rear upper corner resides what appears to be the EVAP (or charcoal) canister for the 7.4 gas engine. I noticed the other day that it has a large barbed fitting facing downward with nothing connected to it clearly visible in the attached photo. When the engine is running air is being sucked into the fitting. My question is: Is there supposed to be a hose or filter or anything attached to this fitting? It just seems odd to me that there is a large barbed fitting sucking air without so much as a filter attached to it.

Thanks in advance for your help. I look forward to finding out exactly what is going on with this.
Attached Thumbnails
Click image for larger version

Name:	100_6112.jpg
Views:	159
Size:	211.1 KB
ID:	122286  
__________________

__________________
8rmesse is offline   Reply With Quote
Old 02-14-2011, 05:03 PM   #2
Rivet Master
 
Keyair's Avatar

 
1984 34.5' Airstream 345
Foothill Ranch , California
Join Date: Mar 2010
Posts: 3,935
Images: 1
First of all...
Congrats, and WELCOME!!!!!!
From me... and i am a new kid on this block!

You story sound wonderful, and the girl sounds sweet... 44k miles... WOW!
Please take lots of photos, and post them in the Classic Photo thread!

Ok, on to your question....
Mine is a 84, and has a similar canister in the rear RH corner of the doghouse, and I thought mine was a charcoal canister... On the 84, its not... its a vac reservior for the cruise control it seems...
Pic...


I suggest you download a copy of the chassis manual here....
This one is the 1987.. might help..
http://service.airstream.com/files/l...3be6cf5637.pdf
__________________

__________________
Keyair is offline   Reply With Quote
Old 02-14-2011, 05:20 PM   #3
Athens GA
 
Myrtle lynn's Avatar
 
1995 28' Excella
1989 34' Excella
1986 31' Sovereign
1987 34.5' Airstream 345
Athens , Georgia
Join Date: Dec 2007
Posts: 578
Images: 4
Quote:
Originally Posted by Keyair
First of all...
Congrats, and WELCOME!!!!!!
From me... and i am a new kid on this block!

You story sound wonderful, and the girl sounds sweet... 44k miles... WOW!
Please take lots of photos, and post them in the Classic Photo thread!

Ok, on to your question....
Mine is a 84, and has a similar canister in the rear RH corner of the doghouse, and I thought mine was a charcoal canister... On the 84, its not... its a vac reservior for the cruise control it seems...
Pic...

I suggest you download a copy of the chassis manual here....
This one is the 1987.. might help..
http://service.airstream.com/files/l...3be6cf5637.pdf
Are those two hose that appear to be cut for the aux heat/ hot water heater? Sorry to get off subject.
__________________
Athens GA
Myrtle lynn is offline   Reply With Quote
Old 02-14-2011, 05:21 PM   #4
Athens GA
 
Myrtle lynn's Avatar
 
1995 28' Excella
1989 34' Excella
1986 31' Sovereign
1987 34.5' Airstream 345
Athens , Georgia
Join Date: Dec 2007
Posts: 578
Images: 4
Quote:
Originally Posted by MEANlowGREEN
Hello fellow Airstream enthusiasts. I am a relatively new Airstream owner having bought my former bosses 1988 Airstream 345 back in October 2010. This is my first RV of any kind and I remember when my boss bought it new. He took good care of the old girl and stored it indoors when possible only putting 44,000 miles on her in the 22 years of ownership. I had always admired it but really never dreamed he would ever sell it or that I would be able to afford it but when I decided I wanted a motorhome this is the only thing I wanted to own so I asked and it's now mine. I have been fixing little things here and there and have made a couple of short trips with it and I have been having a blast! I have been enjoying learning from searching and reading the forums but this is my first post.

I have what should be a pretty simple question for someone to answer but I have not been able to find the answer by searching the forums or Google so here goes. In the right front wheel housing in the rear upper corner resides what appears to be the EVAP (or charcoal) canister for the 7.4 gas engine. I noticed the other day that it has a large barbed fitting facing downward with nothing connected to it clearly visible in the attached photo. When the engine is running air is being sucked into the fitting. My question is: Is there supposed to be a hose or filter or anything attached to this fitting? It just seems odd to me that there is a large barbed fitting sucking air without so much as a filter attached to it.

Thanks in advance for your help. I look forward to finding out exactly what is going on with this.
I have an 87 and will look to see if anything is connected to it.
__________________
Athens GA
Myrtle lynn is offline   Reply With Quote
Old 02-14-2011, 05:30 PM   #5
Rivet Master
 
Keyair's Avatar

 
1984 34.5' Airstream 345
Foothill Ranch , California
Join Date: Mar 2010
Posts: 3,935
Images: 1
Yes, indeedy, thats where they were cut!
__________________
Keyair is offline   Reply With Quote
Old 02-14-2011, 05:36 PM   #6
Athens GA
 
Myrtle lynn's Avatar
 
1995 28' Excella
1989 34' Excella
1986 31' Sovereign
1987 34.5' Airstream 345
Athens , Georgia
Join Date: Dec 2007
Posts: 578
Images: 4
Quote:
Originally Posted by Keyair
Yes, indeedy, thats where they were cut!
Didn't feel like dealing with it anymore.? I think it's a great concept. I just got my 345 and not to familiar with it yet. I am sure I will be cutting mine once I have a problem. Lol.
__________________
Athens GA
Myrtle lynn is offline   Reply With Quote
Old 02-14-2011, 05:43 PM   #7
moderator
Commercial Member
 
Airslide's Avatar

 
2014 23' FB International
Currently Looking...
Wilton , California
Join Date: Aug 2008
Posts: 1,705
Images: 50
Send a message via Yahoo to Airslide
Welcome MEANlowGREEN!

Glad to have you part of the forums...

Vinnie
__________________
"Old fashioned service on your late model Airstream"

https://www.facebook.com/VinniesNort...ir?ref=tn_tnmn
Airslide is offline   Reply With Quote
Old 02-14-2011, 06:28 PM   #8
3 Rivet Member
 
Join Date: Sep 2010
Posts: 159
Images: 15
Thank you for that link. My '88 is built on an '87 P30 chassis so that manual will come in very handy. I had downloaded a manual from the Workhorse site with some useful information but so much has changed in the 24 years it is only useful as a guideline. This is perfect!
__________________
8rmesse is offline   Reply With Quote
Old 02-15-2011, 10:13 AM   #9
3 Rivet Member
 
Join Date: Sep 2010
Posts: 159
Images: 15
Thanks for all the warm welcomes. I am loving my Airstream and this site has a wealth of information. I visit it on nearly a daily basis, sometimes to research, other times just to read random threads. Keyair, the canister I am speaking of is in the right hand wheel well, not the doghouse. The empty fitting measures 1 3/4, the fitting next to it that does have a hose attached runs to one of two air pumps (the one on the lower front portion of the engine) I'm all but positive it it is an emissions related component, just not sure if anything is supposed to be connected to that fitting or not. The fact that is is barbed (or flared) on the end sure makes me think it should have a hose or something clamped on it. Thanks again for helping.

Oh yeah, I went through the chassis manual 3 times and didn't find a picture that accurately represented the canister in question. It may be in there but there aren't any pictures that look close enough to it to know that it is what I am looking at... Great manual though, I am lucky to have it.
__________________
8rmesse is offline   Reply With Quote
Old 02-16-2011, 01:05 PM   #10
Rivet Master
 
Keyair's Avatar

 
1984 34.5' Airstream 345
Foothill Ranch , California
Join Date: Mar 2010
Posts: 3,935
Images: 1
Ok, glad that helped a little!
I spent a day or two downloading and saving them to my computer, but I found its easier to and then printing everything I could find, and now I have 2 full thick ring binders with it all divided into sections!
Here is what I have:
AS Owners Manual.
AS Service Manual
Chassis service Manual
Kohler Genset Manuals(Service, parts, and instalation)
A&E Awning Manual
Also I downloaded and printed a bunch of other stuff that is useful.

So yours has the twin air pumps?
With the engine running, you say you can feel suction there?
Interesting....
__________________
Keyair is offline   Reply With Quote
Old 02-16-2011, 01:42 PM   #11
Rivet Master
 
Keyair's Avatar

 
1984 34.5' Airstream 345
Foothill Ranch , California
Join Date: Mar 2010
Posts: 3,935
Images: 1
Delving into my collection of manuals and the like I found something...

In my 1984 Chevy manual I saw a mention of a "Secondary Air Injection Pump Silencer"

A Search online took me to Wikipedia, and here is a paragraph from that site..
The interesting comment is the very last line...

Pumped air injection
Pumped air injection systems use a vane pump turned by the engine via a belt. The pump's air intake is centrifugally filtered by a rotating screen to exclude dirt particles large enough to damage the system. Air is delivered under pressure to the injection point(s). A check valve prevents exhaust forcing its way back through the air injection system, which would damage the pump and other components.
Carbureted engines' exhaust raw fuel content tends to spike when the driver suddenly releases the throttle. To prevent the startling and potentially damaging effects of the explosive combustion of this raw fuel, a diverter valve is used. This valve senses the sharp increase in intake manifold vacuum resulting from the sudden closure of the throttle, and diverts the air pump's outlet to atmosphere. Usually this diverted air is routed to the engine air cleaner or to a separate silencer to muffle objectionable pump noise.
__________________
Keyair is offline   Reply With Quote
Old 02-16-2011, 06:32 PM   #12
3 Rivet Member
 
Join Date: Sep 2010
Posts: 159
Images: 15
That's probably what it is an intake muffler for the air pump. Yes, I feel quite a bit of suction at idle but since it is attached to an air pump that makes sense. I still wonder if there should be a filter attached to the fitting though.... I have all the owners manuals that came with the Airstream new, even the bill of sale and options list. I have manuals for everything including the Airstream manual, the Chevrolet manuals, the manual for the Kwikee electric steps, the cruise control the hydraulic levelers even the microwave, Emerson Insta-Hot water heater and so on. The manuals even show how to install and troubleshoot most of the items. The original owber saved everything and I am glad. They also saved all the receipts for service and repair work as well. So the chassis manual was a welcome addition to my paperwork although I'll probably never print it out. I don't mind referencing it on my laptop which is always in the motorhome with me. If someone has an '87-88 and can look up in the rear upper corner of the front right hand wheel well to see if anything is attached to that fitting on their unit my mystery will be solved, I guess it's just bad timing since a lot of units are in storage right now... I appreciate all of your help though.
__________________
8rmesse is offline   Reply With Quote
Old 02-16-2011, 06:35 PM   #13
Rivet Master
 
Keyair's Avatar

 
1984 34.5' Airstream 345
Foothill Ranch , California
Join Date: Mar 2010
Posts: 3,935
Images: 1
If that is what it is, I would think that there should be no suction....
From what I read and posted it is an vent out item, not suction.
Is yours a TBI motor?
__________________
Keyair is offline   Reply With Quote
Old 02-17-2011, 04:47 AM   #14
3 Rivet Member
 
Join Date: Sep 2010
Posts: 159
Images: 15
It is a carbureted engine. I am pretty sure the open port is where the air pump is drawing it's air from (it has to intake the air from some place) still I am left wondering is there should be a hose or something attached to it. After all, why is it a barbed fitting if there isn't supposed to be a hose and clamp attached? Of course the answer could be as simple as "because that's the way they made it" but it really has me perplexed. I am less worried now that I know that the suction is coming from an engine mounted pump and not the carburetor intake but I still would be much more comfortable driving the ol' girl if I knew that everything was hooked up the way GM intended it to be. Honestly all this eighties technology emissions equipment is just a jumbled up nightmare. In my younger days I would probably be ripping it all off just as fast as I possibly could but even though emissions tests are only performed on 1996 and up vehicles (when the mandatory switch to OBD-2 was made) in my county ('87-'95 is just a visual inspection to check that all equipment is still installed and nobody EVER does it) I will leave it in place. It would probably run better stripped of all that crap though. I'm certain not spinning two air pumps would free up some horsepower, still it is going to stay. I'm sure it would hurt the resale value to remove it and someday the government might require emissions testing even on older vehicles if for no reason but to force vehicles off the road (much like California). Thanks again for all your help. You seem to be as interested in solving this mystery as myself now. Don't lose any sleep over it though. Somewhere there is a person who can just bend down, look in their wheel well and tell me if there is supposed to be a hose attached to that fitting or not, LOL ) Thanks again for all your efforts.
__________________

__________________
8rmesse is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
'67 Caravel Door lock Question vonzellen Doors & Locks 14 11-29-2011 02:26 PM
LP regulator question GAT LP Gas, Piping, Tanks & Regulators 17 05-09-2011 08:09 AM
Polishing Question NicheVintage Cleaning, Stripping & Polishing 48 02-08-2011 01:04 PM
A 'SMART' question.... FreshAir On The Road... 10 02-06-2011 10:00 PM
Trailering Question Cracker Jacks, Stabilizers, Lifting and Leveling 14 01-02-2011 03:55 PM


Virginia Campgrounds

Reviews provided by




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 06:12 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.