Fuel Vapor seperator repair

A

adam metzger

New member
Oct 12, 2016
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Hey all-

No suprise, the PO bypassed the fuel vapor seperator. I removed it and can see why it was by passed. The bottom plate is totally bowed out.

After cleaning it up, and de funking the passages, I need to re attach the bottom plate.

I found Ken H's tutorial on the photo site, but was curious how the JB weld held up? Any thing you'd do different? I was going to use plastic epoxy,
but it's sensitive to some types of plastic.
--
1976 Palm Beach
Austin, TX
 
Adam,

I'd forgotten about that album. And was surprised when I saw the Jan 09
posting date. I guess 7-1/2 years isn't too bad for such a simple repair
-- it's still not leaking. Kudos to JBWeld!

Ken H.

On Sun, Nov 27, 2016 at 12:02 PM, Adam Metzger
wrote:

> Hey all-
>
> No suprise, the PO bypassed the fuel vapor seperator. I removed it and
> can see why it was by passed. The bottom plate is totally bowed out.
>
> After cleaning it up, and de funking the passages, I need to re attach the
> bottom plate.
>
> I found Ken H's tutorial on the photo site, but was curious how the JB
> weld held up? Any thing you'd do different? I was going to use plastic
> epoxy,
> but it's sensitive to some types of plastic.
> --
>
 
Would you kindly post a link to the photo page showing the referenced presentation?
Please and thank you!

Dave
--
David del Rio - 75 Avion - Raymond, CA
 
I tried fixing mine a couple of times but it still pukes all over when I fill up.

I'm just going to buy one from Jim as expensive as it is

________________________________
From: Gmclist on behalf of David Horowitz
Sent: Monday, November 28, 2016 3:47:13 PM
To: gmclist
Subject: Re: [GMCnet] Fuel Vapor seperator repair

Would you kindly post a link to the photo page showing the referenced presentation?
Please and thank you!

Dave
--
David del Rio - 75 Avion - Raymond, CA

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keith (and All),

being the neub that i am, i do not understand what role the Vapor Separator plays in fuel burping back when filling up.

please help me to understand the issue... as i thought it was just 'the nature of the beast' that the 70's era filler was prone to spitting up once
you trick the pump handle with a piece of swimming pool noodle. that being a result of pressurization of the fuel system in the coach caused by the
tight seal between the nozzle and filler neck.

the more detail you can provide... the better, as i'm new to this. thanks for your time!

best,
dave
--
David del Rio - 75 Avion - Raymond, CA
 
There is this
http://www.zip-corvette.com/catalog/product/view/id/11698/s/70-74-gas-tank-plastic-vapor-separator/

On Mon, Nov 28, 2016 at 4:29 PM David Horowitz
wrote:

> keith (and All),
>
> being the neub that i am, i do not understand what role the Vapor
> Separator plays in fuel burping back when filling up.
>
> please help me to understand the issue... as i thought it was just 'the
> nature of the beast' that the 70's era filler was prone to spitting up once
> you trick the pump handle with a piece of swimming pool noodle. that
> being a result of pressurization of the fuel system in the coach caused by
> the
> tight seal between the nozzle and filler neck.
>
> the more detail you can provide... the better, as i'm new to this. thanks
> for your time!
>
> best,
> dave
> --
> David del Rio - 75 Avion - Raymond, CA
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
As I understand it, the fuel vapor seperator keeps liquid fuel from making it up front to the vapor, but allowing fuel vapor into the canister in the
front passenger wheel well.if liquid fuel makes it into the seperator, the ball floats and closed the needle valve. This is part of the early stages
of emission controls in the 70s, but can apparently cause venting issues if blocked or bypassed.
--
1976 Palm Beach
Austin, TX
 
> keith (and All),
>
> being the neub that i am, i do not understand what role the Vapor Separator plays in fuel burping back when filling up.
>
> please help me to understand the issue... as i thought it was just 'the nature of the beast' that the 70's era filler was prone to spitting up
> once you trick the pump handle with a piece of swimming pool noodle. that being a result of pressurization of the fuel system in the coach caused
> by the tight seal between the nozzle and filler neck.
>
> the more detail you can provide... the better, as i'm new to this. thanks for your time!
>
> best,
> dave

Dave,

The vapor separator or vapor valve has nothing to do with the coach puking fuel during fueling. As stated down the thread, it sole purpose is to keep
liquid fuel from getting to the carbon canister.

If you want to stop the puking fuel, you probably want to separate the fill vent lines. I was having a bad time fueling at all (45mins) but I finally
figured it out and wrote about it in a message called "Recommending High T". If you go to the top right of the forum page and put that in the search
box, you will get a bunch of stuff. Now go left and click "subject only". You will have the thread in archeological order (Older is lower) and the
first post is what you want. You should take the time to read the whole thread.

Matt

--
Matt & Mary Colie - Members GMCMI, GMCGL, GMCES
'73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
Now with both true Keyless and remote entry
SE Michigan - Twixt A2 and Detroit
 
My puking is from the vapor separator check valve. Thats the one I tried to fix. I think it's sealed properly but the ball float isn't shutting off flow when fuel comes in.

FWIW I have dual 1/2" vent lines and I can still get burping at the filler nozzle if I'm not careful.

I can hear when it's getting full, if I'm smart and shut it off, let it settle, restart slower it doesn't happen.

Being smart is usually my problem

________________________________
From: Gmclist on behalf of Matt Colie
Sent: Tuesday, November 29, 2016 4:10:41 PM
To: gmclist
Subject: Re: [GMCnet] Fuel Vapor seperator repair

> keith (and All),
>
> being the neub that i am, i do not understand what role the Vapor Separator plays in fuel burping back when filling up.
>
> please help me to understand the issue... as i thought it was just 'the nature of the beast' that the 70's era filler was prone to spitting up
> once you trick the pump handle with a piece of swimming pool noodle. that being a result of pressurization of the fuel system in the coach caused
> by the tight seal between the nozzle and filler neck.
>
> the more detail you can provide... the better, as i'm new to this. thanks for your time!
>
> best,
> dave

Dave,

The vapor separator or vapor valve has nothing to do with the coach puking fuel during fueling. As stated down the thread, it sole purpose is to keep
liquid fuel from getting to the carbon canister.

If you want to stop the puking fuel, you probably want to separate the fill vent lines. I was having a bad time fueling at all (45mins) but I finally
figured it out and wrote about it in a message called "Recommending High T". If you go to the top right of the forum page and put that in the search
box, you will get a bunch of stuff. Now go left and click "subject only". You will have the thread in archeological order (Older is lower) and the
first post is what you want. You should take the time to read the whole thread.

Matt

--
Matt & Mary Colie - Members GMCMI, GMCGL, GMCES
'73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
Now with both true Keyless and remote entry
SE Michigan - Twixt A2 and Detroit

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GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Thank you Matt... will do just as you've advised.

Dave (who's at least a tiny bit less overwhelmed by his GMC today, than he was yesterday.)
--
David del Rio - 75 Avion - Raymond, CA
 
> Thank you Matt... will do just as you've advised.
>
> Dave (who's at least a tiny bit less overwhelmed by his GMC today, than he was yesterday.)

Dave,

Most new owners are overwhelmed by the power that the community unleashes. I was (a decade ago) and remember the time well. All I can say is - Hang
ON.

The truly great thing is that this lasts about a year and then you are just so glad to have the offered guidance that you stand back and wonder how
those unfortunates that bought an old (in this case half the age of a GMC) ever get by....

The answer for the others unfortunately is... They frequently don't.
They get stalled by lack of parts or accurate information and then the coach is allowed to settle into the grass somewhere.

My next door neighbor has wanted a coach for years. He would have been one of these, but he got a good little SOB, and was fortunate to have someone
that was able to guide him though some things.

Matt
--
Matt & Mary Colie - Members GMCMI, GMCGL, GMCES
'73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
Now with both true Keyless and remote entry
SE Michigan - Twixt A2 and Detroit
 
I get your drift Matt.

At this point my coach is spending more time on a lift than on the highway, but I do see some light at the end of the ramps I built. It's not just
the coach, I've got my own issues keeping me off the road as well. I'm fortunate to have some folks who are directly helping me get things
straightened out but I come to this forum so as to not lean on them all the time... and also to get to know the community better.

I continue to poke into the dark corners of the GMCforum reading old threads to learn about the issues and ideas of others. Often I am in awe at the
technical level of expertise and creativeness found here, to say nothing of the automotive and RV systems experience of the community members. No
doubt my TZE would be sitting in the weeds if not for this forum.

Adam and all... I did not mean to hijack this thread!

Have a great day all.
Dave
--
David del Rio - 75 Avion - Raymond, CA
 
No worries David. Being a noob myself, I'm glad I'm not the only one asking noob questions.
:d

This group of extremely smart and generous people have helped me more in the last month than that know.

I'm glad you guys exist.

After crawling under the coach today and realizing than both front shocks are in effect useless (one is broken, the other is missing the grommet),
I got a little overwhelmed.

Then I thought about some of these guys that have been doing this for years and needs to remind myself this is a long game.

--
1976 Palm Beach
Austin, TX
 
Just remember it wasn't that long ago most of us were noobs too. we remember what it's like

________________________________
From: Gmclist on behalf of Adam Metzger
Sent: Wednesday, November 30, 2016 3:21:32 PM
To: gmclist
Subject: Re: [GMCnet] Fuel Vapor seperator repair

No worries David. Being a noob myself, I'm glad I'm not the only one asking noob questions.
:d

This group of extremely smart and generous people have helped me more in the last month than that know.

I'm glad you guys exist.

After crawling under the coach today and realizing than both front shocks are in effect useless (one is broken, the other is missing the grommet),
I got a little overwhelmed.

Then I thought about some of these guys that have been doing this for years and needs to remind myself this is a long game.

--
1976 Palm Beach
Austin, TX

_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
> Then I thought about some of these guys that have been doing this for years and needs to remind myself this is a long game.

Thanks for the reminder, well said! Sorry to hear about your front end issues. Fortunately changing the shocks is not a terrible job. Good luck.

Best,
Dave
--
David del Rio - 75 Avion - Raymond, CA
 
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