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 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 12-13-2005, 01:56 AM   #1
evan
Registered User
 
evan's Avatar
 
Join Date: Jul 2005
Location: SK, Canada
Posts: 488
pressure in gas tank?

Today when I spun the gas cap off of my truck it made a "pshht" sound like it was releasing pressure or letting air in, but I don't know which. What could have caused that?

My guess is that I messed something up by removing the carbon canister and just plugging the return line. Was that also the way that air is allowed back into the tank?
__________________
Evan B.
evan is offline   Reply With Quote
Old 12-13-2005, 09:18 AM   #2
87 STEPPER
STILL PLAYS WITH TRUX
 
87 STEPPER's Avatar
 
Join Date: Nov 2002
Location: Melbourne, Fla.
Posts: 2,764
Thumbs up Re: pressure in gas tank?

Is this the '78 in your sig?

I would undo what you messed with and see if it still does it.
__________________
~~Bruce~~

MY 87 STEPPER

MY 99 2D/WD TAHOE
87 STEPPER is offline   Reply With Quote
Old 12-13-2005, 12:41 PM   #3
Captkaos
www.73-87chevytrucks.com
 
Captkaos's Avatar
 
Join Date: Dec 1999
Location: Birmingham, AL
Posts: 6,935
Re: pressure in gas tank?

Sounds like you plugged the vent line. What all did you plug? I think you can get a vented gas cap.
__________________
Chris Lucas
1973 Chevy C-10
1978 GMC Jimmy (2WD) - SOLD
1987 R10 twin turbo LS
1991 R3500 SRW CrewCab
1985 K5 diesel swapped project
1989 K5 2WD conversion w/ Vette susp Project
Captkaos Customs
73-87chevytrucks.com
Captkaos is offline   Reply With Quote
Old 12-13-2005, 01:03 PM   #4
evan
Registered User
 
evan's Avatar
 
Join Date: Jul 2005
Location: SK, Canada
Posts: 488
Re: pressure in gas tank?

Yes, my truck is a '78 and it originally came with a carbon canister, mounted in the engine bay behind the driver side headlight, that retrieves unburnt fuel to (I think) route it back to the gas tank. When I did the swap from 305 to 350 I also got a new Edelbrock carburator, so I didn't think I was able to hook the canister back up. Once I had all of the hoses unplugged from it, the only unused hose left in the truck was one line that goes back to the gas tank. That is the one that I plugged.
__________________
Evan B.
evan is offline   Reply With Quote
Old 12-13-2005, 01:05 PM   #5
Andy4639
Old member
 
Andy4639's Avatar
 
Join Date: Jan 2002
Location: Liberty, & Garden City S.C. , U.S.
Posts: 19,936
Re: pressure in gas tank?

If you run the motor for very long peroids without a lot of gas in the tank it can cause trouble. Either redo what you did or put a vented cap on it or a vent line. If it sucks on the tank long you will wear the fuel pump out quicker, and it could cause vacum troubles in the fuel system.
__________________
1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver
Seeing the USA in a 71


Upstate SC GM Truck Club
2013,14 and 2016 Hot Rod Pour Tour


http://upstategmtrucks.com/



Get out and drive the truck this summer and have some fun!
It sucks not being able to hear!

LWB trucks rule, if you don't think so measure your SWB!
After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.
Andy4639 is offline   Reply With Quote
Old 12-14-2005, 04:16 AM   #6
evan
Registered User
 
evan's Avatar
 
Join Date: Jul 2005
Location: SK, Canada
Posts: 488
Re: pressure in gas tank?

I think I've figured out what it is for sure. On the recommendation of a buddy, I pulled out what I now know is the fuel vapor caniser and just plugged the line that goes to the gas tank. So... now I have to put it back in. I've got my trusty Haynes manual but it doesn't show where the hoses are routed.
__________________
Evan B.

Last edited by evan; 12-16-2005 at 08:05 PM.
evan is offline   Reply With Quote
Reply

Bookmarks


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 03:23 PM.


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