Phantom Out Of Gas Syndrome (POOGS): Correction and Prevention - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
Carbs and Fuel System
From the gas tank to the carbs
All fuel system discussion

 6Likes
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 81 (permalink) Old 03-23-2011, 07:15 PM Thread Starter
Senior Member
 
cglennon's Avatar
 
Join Date: May 2008
Location: Portland, OR
Posts: 731
iTrader: (0)
 
Send a message via Skype™ to cglennon
Phantom Out Of Gas Syndrome (POOGS): Correction and Prevention

Fergy PM'ed me to suggest making the instructions to correct and prevent POOGS a 'sticky' (Admin function). I think that it is a great idea. Thanks Fergy! So, here are the instructions to correct and prevent POOGS on '85-'06, non-CA models only. If someone has the instructions for CA models, please add them or PM me and I will add them to this post.

Subject: Phantom Out Of Gas Syndrome (POOGS)

Symptoms: Motorcycle stalls repeatedly as the fuel level in the gas tank falls below 1/2 full. Symptoms similar to running out of gas. Switching to Reserve has no effect.

Root Cause: Failed gas tank venting system; clogged gas cap vent and/or gas tank vent tube or a failed check valves within the gas cap vent assembly. This prevents air from entering the gas tank to displace fuel being used by the carburetors, resulting in negative gas tank pressure (or vacuum). Negative gas tank pressure prevents fuel from reaching the carburetors causing the motorcycle to stall.

Verification Steps:
  1. Fuel level at 1/2 tank of gas or less.
  2. Ride for a few miles.
  3. Motorcycle stalls as if out of gas.
  4. Pull over in a safe location.
  5. Open gas cap for 3-5 minutes. This relieves the negative gas tank pressure momentarily.
  6. Close gas cap
  7. With a few extra cranks the motorcycle starts like there is no problem
  8. Go to step #2 and symptoms repeat
Solution: Clean gas cap venting system and verify that the gas cap vent assembly check valves are functioning properly. Optional: The gas tank vent tube (’88 – ’06, non-CA models only) exits in front of the rear tire and may be rubbing against the spinning rear tire, resulting in a clog that resembles black carbon. Relocate the gas vent tube exit, if this is determined to be the debris source.

Gas Tank Venting System Cleaning Instructions: The process looks complicated, but it only takes about 15 minutes. NOTE: Instructions below are for ’85 – ’06, non-CA models only. Adjust accordingly for CA (vapor recovery system) models.

Step I: Clean the gas tank vent tube/exit.
For '85-'87 Models with no gas tank vent tube (click on Attachment 3602 for more information):
  1. These models vent through a small port in the base of the gas cap. The port exit is located in the rear of the gas cap (see attachment above for details.)
  2. Open the gas cap.
  3. Locate the gas tank vent port entrance; a small hole located on the gas tank directly in front of the opened gas cap hinge.
  4. Spray carburetor cleaner or non-chlorinated brake cleaner, using the straw attachment, directly into the gas tank port entrance. The cleaner should exit the rear of the gas cap freely. Have a rag handy to prevent cleaner from running down the sides of the gas tank.
  5. Use a pipe cleaner or small plastic zip tie to unblock a clogged port, if necessary.
For '88-'06 Models with gas tank vent tube:
  1. Place a piece of paper in front of the gas tank vent tube exit. The default (OEM) location is directly in front of the rear tire.
  2. Open the gas cap.
  3. Locate the gas tank vent tube entrance; a small hole located on the gas tank directly in front of the opened gas cap hinge.
  4. Spray carburetor cleaner or non-chlorinated brake cleaner, using the straw attachment, directly into the gas tank vent tube entrance until drips are observed on the piece of paper placed at the gas tank vent tube exit.
  5. Continue spraying until the drips run clear.
Step II: Clean the gas cap vent assembly.
  1. Open the gas cap and remove the key.
  2. Cover the tank inlet tube to prevent dropping parts in the tank. A large rag or towel is best as it will also help catch small parts and prevent them from falling on the floor (where they can be lost).
  3. Remove the two brass screws located on the bottom of the gas cap that hold the latch mechanism in place.
  4. Remove the latch mechanism. Note: there are loose components in the base that covers the latch spring.
  5. Inspect the latch, clean as necessary and then set aside.
  6. There are five small loosely mounted springs on the underside of the gas cap. They can be left in place for this operation or removed and set aside for safe keeping.
  7. Remove the small metal collar located on the end of the key cylinder’s male connector. The collar acts like a bearing between the key cylinder and previously removed latch assembly. It is loose and easily lost. Slip it off and put it aside for safe keeping.
  8. Hold the gas cap vent assembly in place while removing the two short screws located on the base of the gas cap vent.
  9. Wiggle the gas cap vent assembly back and forth to loosen it from and prevent damage to the gasket which is glued to the gas cap cover.
  10. Inspect the gas vent gasket for tears or bulges. The outline of the venting path depressed into the gasket should be visible (this is normal). Gently wipe with a clean cloth. Inspect the cloth used for signs of debris.
  11. Remove the small round plastic check valve/liquid separator located on the underside of the gas cap vent assembly (a pair of small needle nose pliers works well). Be careful not to damage the silicone valve covering the base of the check valve. This is the valve that allows air to enter the gas tank to relieve negative pressure. Remove the check valve gasket as well and place it aside.
  12. Inspect and clean the check valve. Pay close attention to cleaning the tiny 90 degree elbow which leads to the vent hole.
  13. Inspect the silicone valve located on the underside of the valve. It should be soft, pliable and moving freely.
  14. Inspect the small holes behind the silicone valve. Clean as necessary.
  15. Inspect the silicone check valve mounted in the gas cap vent assembly. This valve helps relieve positive gas tank pressure. It should be soft, pliable and moving freely.
  16. Inspect and clean the gas cap vent assembly air channels and vent hole. Pay special attention to the very small vent hole leading to the 90 degree elbow in the small round plastic check valve/liquid separator removed previously. This tiny hole is easily blocked by debris.
  17. Reassemble in reverse order.
Step II: Preventative maintenance.
  1. Repeat Step I frequently (at least once a year) to keep the gas tank vent line free of debris. Keeping the gas tank vent line clean will help prevent debris from reaching the gas cap vent assembly where it can easily block the air channels or small vent hole.
Jr Mullins and Akright like this.


Chris Glennon - Portland, OR

Last edited by cglennon; 04-20-2013 at 04:07 PM.
cglennon is offline  
Sponsored Links
Advertisement
 
post #2 of 81 (permalink) Old 03-23-2011, 09:36 PM
Senior Member
 
clock152's Avatar
 
Join Date: Jul 2009
Location: Glenpool, Oklahoma
Posts: 900
iTrader: (1)
 
Sticky please!
clock152 is offline  
post #3 of 81 (permalink) Old 03-24-2011, 12:43 AM
Senior Member
 
Ceal's Avatar
 
Join Date: Aug 2010
Posts: 2,687
iTrader: (2)
 
great post!
Ceal is offline  
 
post #4 of 81 (permalink) Old 03-31-2011, 07:09 PM
Patriot Guard Rider
 
The DEUCE's Avatar
 
Join Date: Jan 2011
Location: Torrance, CA
Posts: 825
iTrader: (20)
 
Nice write up but I need the CA Version.

1986 Black Kawasaki Vulcan VN750 "Black KAWK"
VN750 #9300 & VROC #33453

EMGO Handlebar, V&H Exhaust, Drop Shocks, Raised/Painted Fork, MeanStreak Seat, Tank Bib, ME880 Oversize Tires, Engine Guard, Custom Mirrors, Chris Products Turn Signals, Ear Shave, 150/42 Jets, PINGEL Fuel Valve, MCCT, Volt Meter, Shendegen R/R, AGM Battery, Coastered, .020 Coils, Relo Gauges & Headlamp, SilverStar Ultra, LED Flashing Brake Light, Center Stand Delete, WOLO Airhorn.
The DEUCE is offline  
post #5 of 81 (permalink) Old 04-01-2011, 09:20 AM
Members who have donated towards server costs
 
fergy's Avatar
 
Join Date: Mar 2006
Location: Kyle, Texas
Posts: 4,054
iTrader: (3)
   
Nice! Thanks for doing this, and thanks to the admin for making it a sticky!

Fergy
Kyle, TX VN750.com member #707 VROC#19556
2002 VN1500 Classic
Spline Lube Procedure, with photos, R/R Relocation and Coil Mod
Rusty Tank Cleaning!
Electrical Fault Finding Flowchart
SEAFOAM JUNKIE!


fergy is offline  
post #6 of 81 (permalink) Old 04-02-2011, 10:46 PM
Members who have donated towards server costs
 
Join Date: Aug 2010
Location: chaffee mo.
Posts: 29
iTrader: (0)
 
us from ca

how can you tell a us from ca bike

1985 vulcan 700
ngk dp6ea-9
backrest
Custom radiator cover
Custom Mirrors
Fork Bag...
Custom tank trim
ninja54 is offline  
post #7 of 81 (permalink) Old 04-02-2011, 10:57 PM
Member
 
Join Date: Mar 2011
Location: Canon City/Colorado Springs, CO
Posts: 57
iTrader: (0)
 
After shutting off the motorcycle I hear a very loud venting noise from the gas tank and have figured I might as well clean both as said above. Question, you say to use carb cleaner on the vent hose, won't that eat the rubber alive? Also once I take off the tank cover/latch to clean in the 2nd part do I clean that with carb cleaner as well???

Also I couldn't seem to locate the end of that vent hose you say it comes out by the rear tire, where exactly if you don't mind me asking?

I also just bought a sack of marbles and am going to marble her tonight or tomorrow and play around with the air/fuel screws starting off at 2 turns
Unclemoney is offline  
post #8 of 81 (permalink) Old 04-02-2011, 11:10 PM Thread Starter
Senior Member
 
cglennon's Avatar
 
Join Date: May 2008
Location: Portland, OR
Posts: 731
iTrader: (0)
 
Send a message via Skype™ to cglennon
Quote:
Originally Posted by ninja54 View Post
how can you tell a us from ca bike

1985 vulcan 700
ngk dp6ea-9
backrest
Custom radiator cover
Custom Mirrors
Fork Bag...
Custom tank trim
Sorry for the confusion on the reference to CA. CA refers to CAlifornia emissions. The California (CA) models have a gas vapor recovery system. Basically a charcoal canister and set of purge valves designed to capture gasoline vapor and recycle them back into the system (now standard on cars). You have a CA emissions model if there are two vent tubes at the base of the gas tank (visible when the seat is removed). The non-CA models have a single gas tank vent tube.


Chris Glennon - Portland, OR

Last edited by cglennon; 04-20-2013 at 04:09 PM.
cglennon is offline  
post #9 of 81 (permalink) Old 04-02-2011, 11:29 PM Thread Starter
Senior Member
 
cglennon's Avatar
 
Join Date: May 2008
Location: Portland, OR
Posts: 731
iTrader: (0)
 
Send a message via Skype™ to cglennon
Quote:
Originally Posted by Unclemoney View Post
After shutting off the motorcycle I hear a very loud venting noise from the gas tank and have figured I might as well clean both as said above. Question,

1) you say to use carb cleaner on the vent hose, won't that eat the rubber alive?

2) Also once I take off the tank cover/latch to clean in the 2nd part do I clean that with carb cleaner as well???

3) Also I couldn't seem to locate the end of that vent hose you say it comes out by the rear tire, where exactly if you don't mind me asking?

4) I also just bought a sack of marbles and am going to marble her tonight or tomorrow and play around with the air/fuel screws starting off at 2 turns
The loud venting noise is a GOOD thing! It means that the venting system is functioning properly (i.e., air is enter the tank and making that noise). However, a 15 minute cleaning will not hurt and will provide peace of mind that the system is indeed free of debris.

1) To clean, just use a rubber safe cleaner that will not leave a sticky residue to clean the rubber vent line, like non-chlorinated brake cleaner or a carb cleaner that is easy on rubber parts. I like non-chlorinated brake cleaner because I can use it in other applications, like cleaning the mass-flow air sensors in my car. You decide what works best for you (everyone has their favorites).

2) You can use the cleaner selected above to clean all parts of the gas tank venting system. Again, whatever works best for you or is your favorite.

3) The default OEM exit for the gas tank vent tube snakes through the frame to exist directly in front of the rear tire, about mid point. However, the prior owner (if applicable) may have move the it. Trace/follow the gas tank vent tube through the frame or spray your cleaner of choice and look for the drips to locate the actual exit point.

4) Marbling - Search the existing threads or start a new one. This STICKY thread is devoted to POOGS


Chris Glennon - Portland, OR
cglennon is offline  
post #10 of 81 (permalink) Old 04-07-2011, 06:50 AM
Big Dumb Viking
 
asbrand's Avatar
 
Join Date: Apr 2009
Location: Marietta, GA
Posts: 597
iTrader: (0)
 
Send a message via AIM to asbrand Send a message via MSN to asbrand Send a message via Yahoo to asbrand
Just had POOGS happen to me on my way home from work a few minutes ago. Luckily...it happened as I was pulling into my neighborhood...and I'm just the 3rd house... Coasted to my driveway.

Looks like I have something to do later today after I wake up.

Thanks for this write-up!

.
.
.
-Az
http://www.asbrand.com

1989 Kawasaki Vulcan 750

Upgrades so Far:
Coastered
R/R relocated
Analog Voltmeter
PFIII Windshield
RAM GPS Mount w/Garmin GPS
Cigarette Lighter Power Adapter
Saddlemen's Classic Explorer Seat
Pro-Tac Driver's Backrest
LED Tail Light
LED Rear Turn Signals
Luggage Rack
Storage Trunk
Engine Guard w/Highway Pegs
Radiator Grill Cover
Turn Signal Relocation Bracket
Saddlebags
Floorboards
asbrand is offline  
Sponsored Links
Advertisement
 
Reply

Bookmarks

Tags
1/2 tank , phantom out of gas , poogs , stalling

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

Once registered, your User Name"cannot be changed". We can make exceptions within 7 days, but after that, it is set in stone.

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 email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome