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Howell Fuel Return Line in Vent Line [message #366603] Wed, 08 September 2021 17:37 Go to next message
Tom Katzenberger is currently offline  Tom Katzenberger   United States
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I am installing a Howell EFI. Has anyone had any problem with returning the fuel via the vent line in lieu of putting a hole in the fill tube?
Are there any opinions of one method vs. the other method?

Thanks,
Tom K.


Tom & Oki Katzenberger, Kingsville, Maryland, 1977 23' Birchaven, 455 C.I.D., Micro Level, Howell EBL-EFI Spark Control, Macerator, York Air Compressor, 6 Wheel Disc, Quadra Bag, Onan W/Bovee Ignition
[GMCnet] Re: Howell Fuel Return Line in Vent Line [message #366617 is a reply to message #366603] Wed, 08 September 2021 22:16 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Returning fuel into the vent line can work, however there will be time when
that will back fire.
Drill a hole and epoxy a brass fitting on the filler tube.

On Wed, Sep 8, 2021 at 3:37 PM wrote:

> I am installing a Howell EFI. Has anyone had any problem with returning
> the fuel via the vent line in lieu of putting a hole in the fill tube?
> Are there any opinions of one method vs. the other method?
>
> Thanks,
> Tom K.
> --
> Tom & Oki Katzenberger,
> Kingsville, Maryland,
> 1977 23' Birchaven, 455 C.I.D.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>


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Jim Kanomata ASE
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.gmcrvparts.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
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[GMCnet] Re: Howell Fuel Return Line in Vent Line [message #366619 is a reply to message #366617] Thu, 09 September 2021 06:21 Go to previous messageGo to next message
Bikertrash is currently offline  Bikertrash   United States
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Location: Northern Indiana
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Junior Member
As Jim stated, that is the way I did it to help with vapor lock.

On Wed, Sep 8, 2021 at 11:16 PM Jim Kanomata wrote:

> Returning fuel into the vent line can work, however there will be time when
> that will back fire.
> Drill a hole and epoxy a brass fitting on the filler tube.
>
> On Wed, Sep 8, 2021 at 3:37 PM wrote:
>
>> I am installing a Howell EFI. Has anyone had any problem with returning
>> the fuel via the vent line in lieu of putting a hole in the fill tube?
>> Are there any opinions of one method vs. the other method?
>>
>> Thanks,
>> Tom K.
>> --
>> Tom & Oki Katzenberger,
>> Kingsville, Maryland,
>> 1977 23' Birchaven, 455 C.I.D.
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>>
>
>
> --
> Jim Kanomata ASE
> Applied/GMC, Newark,CA
> jimk@appliedairfilters.com
> http://www.gmcrvparts.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>


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Scott Campbell
Jack of All, Master of None!
President AMCA River Valley Chapter
1980 FXEF, 1997 XL, 2000 FLHT, 2014 FLD
1982 Chevy G20
1973 GMC Glacier Motorhome
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Scott & Mindy Campbell Northern Indiana 1973 26' Glacier, 88,000 miles, 16" Alcoa Wheels, Rust free frame (painted), Stock air suspension, New fuel lines & sending units, New brake lines, Stock front end, Onan generator Newer Coleman A/C
Re: Howell Fuel Return Line in Vent Line [message #366621 is a reply to message #366603] Thu, 09 September 2021 07:19 Go to previous messageGo to next message
Richard RV   United States
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Using the vent line as a fuel return line is akin to having a wet vent in a residential plumbing waste line. Most codes allow it but require the pipe size be increased. Sewer gases are a lot "friendlier" than volatile liquid gas and vapor, and plumbing pipe is far larger.

What's the advantage of not returning the fuel to the filler neck?

Richard


'77 Birchaven TZE...777; '76 Palm Beach under construction; ‘76 Edgemont waiting its turn
Re: Howell Fuel Return Line in Vent Line [message #366628 is a reply to message #366603] Thu, 09 September 2021 09:40 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Tom,

I answered this too soon in the post below.

If by vent line, you mean the fill vent that runs up to the fill neck, that would have to be good. Once the fill cap is on, that line is doing nothing until the cap is opened again. If you do the High T Mod that I and others have found successful, you can even pick which tank you want the returning fuel to go to.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: Howell Fuel Return Line in Vent Line [message #366644 is a reply to message #366603] Thu, 09 September 2021 13:59 Go to previous messageGo to next message
Tom Katzenberger is currently offline  Tom Katzenberger   United States
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I absolutely plan on the High Tee mod.

I have the tanks out and am installing stainless lines from the pump to the TBI and then back to the tanks some how.

I am trying to figure out what is the best way to return the fuel to the tanks. Not as much interested in the easiest or cheapest. I can Tig weld in the tank or tube as the system has been completely drained washed, zink coated and coated with master coat.

The coach is in the air and all is exposed.

Thank you all for your thoughts, I just haven't settled on which direction to go. I do like Kens idea of dumping it back in the AUX tank. I am worried about the long term results with JB weld in the fill tube.

Thanks again,
Tom K


Tom & Oki Katzenberger, Kingsville, Maryland, 1977 23' Birchaven, 455 C.I.D., Micro Level, Howell EBL-EFI Spark Control, Macerator, York Air Compressor, 6 Wheel Disc, Quadra Bag, Onan W/Bovee Ignition
Re: Howell Fuel Return Line in Vent Line [message #366645 is a reply to message #366644] Thu, 09 September 2021 14:54 Go to previous messageGo to next message
Bill Van Vlack is currently offline  Bill Van Vlack   United States
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On a somewhat similar note...

I have an EFI pump with a check valve for each tank and no longer use the diverter. I'm thinking about doing the 'High T mod' by plugging the hard line vent T going to the Aux tank and splicing in a 3/8" barricade rubber line to the Aux tank vent line, fastened to the hard line going forward, and then teed into the 1/2" vent line about half way up to its connection to the filler vent.

Since I presently have the EFI return going to the fill tube, and understand that with that arrangement return fuel(mostly) goes to the Main tank..... Is there any advantage to installing the diverter such that it returns fuel to either the Main tank (via filler tube) or to the Aux tank via the new vent line based on the position of the dash selector switch so that return fuel goes to the tank that it's coming from?

If not, does it make sense to move the return to the new Aux tank vent line?


Bill Van Vlack '76 Royale; Guemes Island, Washington; Twin bed, full (DS) side bath, Brazilian Redwood counter and settee tops,455, 6KW generator; new owner a/o mid November 2015.
[GMCnet] Re: Howell Fuel Return Line in Vent Line [message #366646 is a reply to message #366645] Thu, 09 September 2021 15:00 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Tom,
I'm sure your aware that when welding on a gas tank empty, you need to fill
with water or purge the gas vapors as it will burst.

On Thu, Sep 9, 2021 at 12:54 PM Bill Van Vlack
wrote:

> On a somewhat similar note...
>
> I have an EFI pump with a check valve for each tank and no longer use the
> diverter. I'm thinking about doing the 'High T mod' by plugging the hard
> line vent T going to the Aux tank and splicing in a 3/8" barricade rubber
> line to the Aux tank vent line, fastened to the hard line going forward, and
> then teed into the 1/2" vent line about half way up to its connection to
> the filler vent.
>
> Since I presently have the EFI return going to the fill tube, and
> understand that with that arrangement return fuel(mostly) goes to the Main
> tank.....
> Is there any advantage to installing the diverter such that it returns
> fuel to either the Main tank (via filler tube) or to the Aux tank via the
> new
> vent line based on the position of the dash selector switch so that return
> fuel goes to the tank that it's coming from?
>
> If not, does it make sense to move the return to the new Aux tank vent
> line?
> --
> Bill Van Vlack
> '76 Royale; Guemes Island, Washington; Twin bed, full (DS) side bath,
> Brazilian Redwood counter and settee tops,455, 6KW generator; new owner a/o
> mid
> November 2015.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>


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Jim Kanomata ASE
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.gmcrvparts.com
1-800-752-7502
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Re: Howell Fuel Return Line in Vent Line [message #366648 is a reply to message #366603] Thu, 09 September 2021 16:07 Go to previous messageGo to next message
Tom Katzenberger is currently offline  Tom Katzenberger   United States
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Jim,

Yes, I fill them with water and leave a torch burning as the water drains out. They are spotless inside and out.

That being said, I must tell you I sincerely appreciate you stepping in and backing me up with such a possibly dangerous situation.

Thank you for not letting step in front of the train.

Sincerely,
Tom K.


Tom & Oki Katzenberger, Kingsville, Maryland, 1977 23' Birchaven, 455 C.I.D., Micro Level, Howell EBL-EFI Spark Control, Macerator, York Air Compressor, 6 Wheel Disc, Quadra Bag, Onan W/Bovee Ignition
Re: Howell Fuel Return Line in Vent Line [message #366654 is a reply to message #366603] Thu, 09 September 2021 19:40 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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Returning the fuel to the tanks via the vent lines can cause a "burp" of fuel when you start refilling due to liquid fuel in the vent lines.

Doing the High-T mod to the vent lines may help, but you need to be sure there is no dips in the vent lines to hold liquid fuel.

Mine is returned to the filler line and the fuel tends to return to the Main (rear) tank. I don't think of them as Main and Aux, more like just front and rear tanks (there are no labels on my fuel switch). Once you get down to 5/8 tank and less, more fuel tends to end up in the Aux tank, especially when going down a long hill. I tend to run on the front tank as much as the rear.


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: Howell Fuel Return Line in Vent Line [message #366677 is a reply to message #366603] Fri, 10 September 2021 12:52 Go to previous message
Tom Katzenberger is currently offline  Tom Katzenberger   United States
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I decided to weld a stainless nipple in the left side of the front (Aux) tank. I hope this is a good solution as there appear to be several good solutions out there. I most liked the fill tube option, but did not feel comfortable with relying on the JB Weld joint. I thought this may be best because it is easy to inspect for leaks or weld failure. I wanted it in the top but just don't have the clearance and I would not be able to inspect weld or metal fatigue.

Has anyone had any back pressure issues with returning the fuel in the side?

Take care,
Tom K.


Tom & Oki Katzenberger, Kingsville, Maryland, 1977 23' Birchaven, 455 C.I.D., Micro Level, Howell EBL-EFI Spark Control, Macerator, York Air Compressor, 6 Wheel Disc, Quadra Bag, Onan W/Bovee Ignition
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