The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevy/GMC Suburbans & Panels Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 06-20-2018, 08:10 AM   #1
Awjunkies
Registered User
 
Join Date: Nov 2015
Location: Gulfport,MS
Posts: 63
LS swap and charcoal canister

I have a 72 k10 with a 5.3/4L80e combo.

When I purchased the vehicle it had the 350/th350 with a "custom" auxiliary tank rigged up. I had a new 21 gallon tank put in and left the aux tank in but not using it. When it gets hot and the the main tank is anywhere past half the fuel pours out of the auxiliary tank fill hose that's capped off.

I know I can just completely disconnect it or plug the large fills out with an expansion type plug but my question is, is anyone else running a vapor canister?

My thought is if there is enough pressure to send the fuel to my aux tank and out the full hose and I just cap it, it will find the next weakest point eventually ruining or over pressurizing lines to the motor, etc.

Am I wrong? Is it needed or cap it and send it?
Posted via Mobile Device
Awjunkies is offline   Reply With Quote
Old 06-20-2018, 10:31 AM   #2
LockDoc
The Older Generation

 
LockDoc's Avatar
 
Join Date: Aug 2006
Location: Montezuma, Iowa
Posts: 25,238
Re: LS swap and charcoal canister

-
I would say that the vapor canister is not doing it's job or something is capped off or plugged up on the system. Get a vented gas cap and put it on, see if that cures the problem....

LockDoc
__________________
Leon

Locksmith, Specializing In Antique Trucks, Automobiles, & Motorcycles

(My Dually Pickup Project Thread)

http://67-72chevytrucks.com/vboard/s...d.php?t=829820

-
LockDoc is offline   Reply With Quote
Old 06-20-2018, 11:05 AM   #3
Awjunkies
Registered User
 
Join Date: Nov 2015
Location: Gulfport,MS
Posts: 63
Re: LS swap and charcoal canister

I'm pretty sure I don't have a canister but I do have the vented cap
Posted via Mobile Device
Awjunkies is offline   Reply With Quote
Old 06-20-2018, 12:27 PM   #4
GMC-YA68
Senior Member
 
GMC-YA68's Avatar
 
Join Date: Mar 2004
Location: Lee's Summit, MO (KC)
Posts: 742
Re: LS swap and charcoal canister

do you have an in-tank fuel pump?
__________________
-Keegan-

'72 Jimmy 4x4 - 5.3/4L65E/NP205 swap
http://67-72chevytrucks.com/vboard/s...d.php?t=663780
GMC-YA68 is offline   Reply With Quote
Old 06-20-2018, 03:44 PM   #5
Awjunkies
Registered User
 
Join Date: Nov 2015
Location: Gulfport,MS
Posts: 63
Re: LS swap and charcoal canister

Negative.
Posted via Mobile Device
Awjunkies is offline   Reply With Quote
Old 06-20-2018, 05:36 PM   #6
Bigdav160
Registered User
 
Bigdav160's Avatar
 
Join Date: Apr 2011
Location: Klein Texas
Posts: 3,852
Re: LS swap and charcoal canister

The vapor canister is located beside the battery behind the right headlamp.

It sounds like the tank is getting pressurized. Do you have a fuel return line on your setup? Or is it a single line?
__________________
My Classics:
'72 K20 Suburban + '65 Dodge Town Wagon
'72 Corvette Roadster +'67 Corvette Roadster
'73 Z-28 Camaro
'63 Ford SWB Uni Pickup
'50 Ford Coupe
Bigdav160 is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
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

Forum Jump


All times are GMT -4. The time now is 07:43 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com