Whoosh! when removing the gas cap - Page 2 - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep CJ Forum > Whoosh! when removing the gas cap

ANOTHER Rockridge4wd Creation!! Spare Tire Carrier Delete The Original 3/8" Ruffstuff Diff Cover!Even Better Heim Pricing! From Ruffstuff

Reply
Unread 07-20-2013, 02:10 PM   #16
adman02
Registered User
1979 CJ7 
 
Join Date: Jul 2008
Location: Durham, NC
Posts: 300
Drove around a bit with evap connected and without. Got the "pssst" each time.

Here's my new theory. The TBI return system pressure is too high. Maybe caused by fuel pressure that's too high???

Or could it be something clogging the tank vents?

Or could it be the LCV or Rollover valve malfunctioning?

Any thoughts?

adman02 is offline   Reply With Quote Quick reply to this message
Unread 07-20-2013, 03:27 PM   #17
xnodesirex
Registered User
1978 CJ7 
 
Join Date: Aug 2012
Location: cincinnati, ohio
Posts: 57
Not to hijack this thread (sorry adman).

I have the same woosh when I change the remove the gas cap (78 304 CJ-7; team rush'd). I always thought it was normal - does this mean its not?
xnodesirex is offline   Reply With Quote Quick reply to this message
Unread 07-20-2013, 06:49 PM   #18
adman02
Registered User
1979 CJ7 
 
Join Date: Jul 2008
Location: Durham, NC
Posts: 300
Perhaps a small whoosh is normal. I dunno. My original was pretty significant though.
adman02 is offline   Reply With Quote Quick reply to this message
Unread 07-20-2013, 07:39 PM   #19
John Strenk
Moderator
 
John Strenk's Avatar
1976 CJ5 
 
Join Date: Feb 2005
Location: Shalersville Ohio
Posts: 13,240
Quote:
Originally Posted by adman02 View Post
Drove around a bit with evap connected and without. Got the "pssst" each time.

Here's my new theory. The TBI return system pressure is too high. Maybe caused by fuel pressure that's too high???

Or could it be something clogging the tank vents?

Or could it be the LCV or Rollover valve malfunctioning?

Any thoughts?
It should still vent someplace.
If the pump puts pressure on one side, it has to drop the pressure on the other side.

It could be either valve. isconnect one at a time...
John Strenk is online now   Reply With Quote Quick reply to this message
Unread 07-21-2013, 06:39 AM   #20
thompsoj22
Registered User
1984 CJ7 
 
Join Date: Aug 2011
Location: ridgecrest, ca
Posts: 320
i would say you fixed it

i have also installed the newer evac canister. also had the purge line t'd to manifold vac and i dont think it was suffecient enough. i put it back with the pcv circuit and it works perfect. use a hard plastic vac hose from the pcv "T" to the canister and adapt it at both ends with fuel line. this will prevent the purge line from collapsing from the high vac at idle. your tank should be pressurized to an extent, this tells you that the fuel vapors are being held in the system and not released into the atmosphere. the fuel spewing back is a topped off or high enough fuel level in the tank to be partially into the filler hose. just another AMC design quirk.
thompsoj22 is offline   Reply With Quote Quick reply to this message
Unread 07-27-2013, 04:54 AM   #21
SJ85CJ7
Registered User
1985 CJ7 
 
Join Date: Jun 2011
Location: Some place between Heaven and Hell, Tennessee
Posts: 74
Now my problem is the reverse, the fill neck on my 85 CJ7 was dimpled from all the years of having a nozzle hanging during refuel and the gas cap would not seat correctly so I fixed it now no more leaking gas when taking a corner fast. Now after starting if I shut down and try to restart it won't, it's like I'm not getting any fuel or I'm getting a vapor lock. I'm running the 4.2L I-6 with a Weber carb with the three port fuel filter (one in two out) no emissions equipment other then the Cat and charcoal canister, minimum vacuum lines. I'm not sure what is going on, I've had the tank down a few time and know that all the lines going to it are new and in the correct places.
__________________
85' CJ7, 258 I6, "Team Rush" Weber 38/MSD 6A, T-176 4-speed, twin-stick Dana 300, DANA 30 fore - AMC 20 aft with stock 2.73 gears, 31" tires, 8k winch, "Dirtworx" rear bumper/tire carrier. My Daily Drive, JustEmptyEveryPocket
SJ85CJ7 is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools






Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.