Anyone wanna check my diagnosis? - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
Carbs and Fuel System
From the gas tank to the carbs
All fuel system discussion

 
LinkBack Thread Tools Display Modes
post #1 of 9 (permalink) Old 09-28-2009, 05:00 PM Thread Starter
Adventuregeek
 
Tiki Mon's Avatar
 
Join Date: Oct 2008
Location: Atlanta, GA
Posts: 162
iTrader: (0)
 
Anyone wanna check my diagnosis?

My guess: stuck float valve in rear carb.

Cranked 'er up Saturday intending to ride. Started, ran a little rough, got rougher... wouldn't run without the choke on. In fact, it only runs with the fuel valve OFF, if I turn it to ON, it quits.

Front plugs are good. Rear plugs are wet with gas. Oily fuel drips from the rear exhaust joint at the block when it's running. Major gasoline smell out the back (the cycle, not me). It will idle, but rev it and it backfires and blows out a puff of smoke.

Of possible interest: about 25 miles ago, it quit on me at an intersection. Wouldn't idle, but would rev slowly higher and higher until I cut the switch. I finally spotted that the rear carb air boot had slipped off. I replaced and tightened it and the cycle ran fine for the rest of the trip.

Any other likely suspects besides the float valve?

Thanks!
-Tiki

Laissez les bon temps rouler!

Coastered, R&R relocation, MCCT's, Koso mirrors, Memphis Shades windshield, Mutazu GA hard bags, big monkey in the saddle. ATGATT: Olympia AST hi-viz jacket, Recon 2 (convertible) pants
Tiki Mon is offline  
Sponsored Links
Advertisement
 
post #2 of 9 (permalink) Old 09-28-2009, 09:39 PM
Senior Member
 
Join Date: Apr 2009
Posts: 209
iTrader: (2)
 
my guess would be the same thing. the float is stuck open so it is dumping fuel down the carb.
6204 is offline  
post #3 of 9 (permalink) Old 09-28-2009, 10:00 PM
Members who have donated towards server costs
 
flitecontrol's Avatar
 
Join Date: Dec 2008
Location: Monroe, LA
Posts: 4,699
iTrader: (14)
 
Tried tapping on it with a screwdriver handle?

I'm keepin' all the left over parts. I'm gonna use 'em to build another bike!
_____________________________________________
"Black Beauty"
1989 VN750 acquired December, 2008, 6,711 miles
Currently 23,298 miles

Old Blue
2001 Honda CMX250 Rebel acquired July, 2008

1987 VN750 project bike, acquired August, 2009, 33,000 miles and balancer sticking out of the case, currently awaiting attention and parts
flitecontrol is offline  
 
post #4 of 9 (permalink) Old 10-13-2009, 03:55 PM Thread Starter
Adventuregeek
 
Tiki Mon's Avatar
 
Join Date: Oct 2008
Location: Atlanta, GA
Posts: 162
iTrader: (0)
 
Yep, stuck float.

Dumped half a can of Seafoam in the tank, ran it every so often for a minute to run the solvent through. Hammered on the carb, shot carb cleaner up the bowl drain. After a day of that and an oil change (gas got past the rings) it was behaving more normally. Took it for a 50-miler and it was back to normal when we got back.

I'll have to pull the carbs someday, I suppose, but NOT YET! :-)
Tiki Mon is offline  
post #5 of 9 (permalink) Old 10-13-2009, 04:26 PM
The Professor
 
lance328's Avatar
 
Join Date: Feb 2008
Location: BUFORD, GEORGIA
Posts: 3,147
iTrader: (15)
   
Get some inline filters on before more debris gets in the carbs.


85 VN700 "Old Yella"

REBUILT ENGINE
CUSTOM PAINT
VANCE & HINES CRUZERS
EAR SHAVED AND RE-JETTED W/K&N'S
DUNLOP ELITE K591 FRONT & REAR
VOLTMETER
SYNTHETIC BRAKE FLUID
SYNTHETIC OIL & GEAR LUBE
PLEXISTAR 2 WINDSHIELD
SPLINES LUBED
ACCT'S GREASED W/TOC SPRINGS
COASTERD
LEATHER SADDLE BAGS
LEATHER TOOL AND ROLL BAG
PICKUP COILS GAPPED AT .018"
NGK CAP, WIRES, IRIDUMS
BARNETT FRICTION PLATES & SPRINGS
CUSTOM GRIPS, MIRRORS, LEVERS
ORIGINAL STATOR & R/R 14.5v
DEKA MF AGM ETX15L

Best Auto/Moto Insurance | Motorcycle Protection Today | FREE Trade-In Quote
lance328 is offline  
post #6 of 9 (permalink) Old 10-13-2009, 06:16 PM
The Reanimater
 
jthill524's Avatar
 
Join Date: Apr 2009
Location: A Little Town Along I-5 in Northern California
Posts: 847
iTrader: (2)
 
Quote:
Originally Posted by Tiki Mon View Post
Yep, stuck float.
I'll have to pull the carbs someday, I suppose, but NOT YET! :-)

JaY



"Veronica"
2002 VN750 Vulcan
Rebuilt Engine
ACCTs lubed w/TOC Springs
Pick-up Coils Gapped at .018"
Splines Lubed
Deka MF AGM EXT15L Battery
NGK Iridium IX Spark Plugs
R/R Relocation Fix
New Rear Rack
Stock Seat Repadded
Ext-BackRest
jthill524 is offline  
post #7 of 9 (permalink) Old 10-13-2009, 09:16 PM
Love My Baby
 
rubyrick's Avatar
 
Join Date: Jun 2008
Location: Hollywood, Florida
Posts: 1,165
iTrader: (1)
   
Hey Jay, powerful message! Sometimes putting off preventative maintenance can have explosive consequences.

Rubyrick

MY BABY...
'05 VN750
16,000 miles +
Kawi tank bib
Kawi rear rack
Small windshield
DEKA M/F battery
VN750.com Grill Cover
LED license plate frame
Clear Alternatives LED brake light
Cortech mini tank bag on rear rack
Pirelli MT66 Tires: 110 front / 150 rear
Splines lubed when tires installed at 10,650 miles
Splines lubed again at 14,400 with stubby valve stem install

Place your mouse on the X below and drag to the O

X
Even though you can't see Him, GOD is there! O
rubyrick is offline  
post #8 of 9 (permalink) Old 10-14-2009, 09:33 AM
Members who have donated towards server costs
 
fergy's Avatar
 
Join Date: Mar 2006
Location: Kyle, Texas
Posts: 4,054
iTrader: (3)
   
I would suggest that for the time being, you get used to turning off the petcock when you park the bike. We all should probably be doing that anyway since you really never know when a float valve will decide to stick open and if the petcock happened to be bad, you could have a nasty situation on your hands. Think about the photo above... If that would have happened when he got home and pulled her into the garage....
An ounce of prevention could save the cost of a bike, or even a house...

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 #9 of 9 (permalink) Old 10-14-2009, 04:41 PM Thread Starter
Adventuregeek
 
Tiki Mon's Avatar
 
Join Date: Oct 2008
Location: Atlanta, GA
Posts: 162
iTrader: (0)
 
Yup, I shut off the fuel when I stop. Believe me, I've seen enough vehicles burn to be paranoid about fuel leaks.

Looking for a small extinguisher to carry too. I watched a few vehicle fires start, and you've only got a couple of minutes at MOST to prevent a total loss. On a cycle, I imagine it's pretty quick.

Laissez les bon temps rouler!

Coastered, R&R relocation, MCCT's, Koso mirrors, Memphis Shades windshield, Mutazu GA hard bags, big monkey in the saddle. ATGATT: Olympia AST hi-viz jacket, Recon 2 (convertible) pants
Tiki Mon is offline  
Sponsored Links
Advertisement
 
Reply

Bookmarks

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