Just got bike, pig rich, bad idle - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
Carbs and Fuel System
From the gas tank to the carbs
All fuel system discussion

Reply
 
LinkBack Thread Tools Display Modes
post #1 of 11 (permalink) Old 07-18-2013, 08:08 PM Thread Starter
I.T. Analyst, Alpha Geek
 
FieroGT42's Avatar
 
Join Date: Jul 2013
Location: SE Iowa
Posts: 157
iTrader: (2)
 
Just got bike, pig rich, bad idle

"New" to me 87 VN750, my first bike and first carbed engine but I'm a very fast learner. Wouldn't idle, rich, stumbling, and the prev. owner said it died on him by the time he got to 3rd gear.

Wouldn't idle at ALL when I tried it, hard to start. Got it home & the idle was set really low. Had to turn it up almost all the way to get 1100 and it fires right up now. Idled rough & rich for < 5 min and died. Set it up to 1300 to keep it running until I fix the AFR problem. I'm guessing I'll have to set it back down once I fix the AFR.

Still pig rich both at idle and revving. Pulled petcock vac & got 1 or 2 drips of fuel. Reconnected, ran for a few min, nothing in the line now so that looks ok to me?

Doesn't look like anyone has ever monkeyed with the idle screws. Anything to check before I go through the hassle of pulling the carbs?

Thanks.

Jason

Last edited by FieroGT42; 07-18-2013 at 09:41 PM.
FieroGT42 is offline  
Sponsored Links
Advertisement
 
post #2 of 11 (permalink) Old 07-18-2013, 10:29 PM
Old Fart
 
Knifemaker's Avatar
 
Join Date: Jun 2004
Location: Catawissa, MO
Posts: 11,788
iTrader: (4)
     
Garage
My guess is unless its been rejetted...you might have some float bowl valves that aren't closing...letting the bowls overflow and flood the motor. Could also be a clog somewhere else in the carb....either way you'll need to yank them and clean them.
Could also be stuck chokes. (Which are just circuits that toss in more fuel)

Check the rubber diaphragms for holes or tears.

Good luck.

If You Are Not Sure If I Am Joking or Not....I AM !!Photos:
http://www.flickr.com/photos/knifemaker1954/sets/
Knifemaker is online now  
post #3 of 11 (permalink) Old 07-18-2013, 11:21 PM
Registered User
 
Join Date: Aug 2011
Location: GreenwoodFrickinLakeNY
Posts: 10,354
iTrader: (8)
   
Try this first....

https://www.vn750.com/forum/showthread.php?t=25458

Could save you from pulling the carbs....and 95% its a stuck float and more than likely the one by yer left leg....



Wolfie is offline  
 
post #4 of 11 (permalink) Old 07-19-2013, 04:21 PM Thread Starter
I.T. Analyst, Alpha Geek
 
FieroGT42's Avatar
 
Join Date: Jul 2013
Location: SE Iowa
Posts: 157
iTrader: (2)
 
Thanks, I'll see if that does it. The left carb does look a little gummy in spots.

Attach hose and "Blow through it". Compressed air or could that mess something up?
FieroGT42 is offline  
post #5 of 11 (permalink) Old 07-19-2013, 04:42 PM
Banned
 
Join Date: Jan 2013
Posts: 2,190
iTrader: (0)
 
You need a petcock rebuild.
wmsonta is offline  
post #6 of 11 (permalink) Old 07-19-2013, 09:40 PM Thread Starter
I.T. Analyst, Alpha Geek
 
FieroGT42's Avatar
 
Join Date: Jul 2013
Location: SE Iowa
Posts: 157
iTrader: (2)
 
I checked the petcock as best I know how. It seems to operate normally by applying vacuum, and there's no fuel coming into the vac line that operates the petcock.

I blew out the carbs backward so I'll see if that made any difference. Otherwise I'm just pulling them for a real cleaning and rebuild if they need it. If they're dirty enough to run this badly I may as well clean them right.
FieroGT42 is offline  
post #7 of 11 (permalink) Old 07-19-2013, 09:52 PM
Banned
 
Join Date: Jan 2013
Posts: 2,190
iTrader: (0)
 
I thought you posted you got a couple of drops of gas out of it. My bad.
wmsonta is offline  
post #8 of 11 (permalink) Old 07-19-2013, 10:39 PM Thread Starter
I.T. Analyst, Alpha Geek
 
FieroGT42's Avatar
 
Join Date: Jul 2013
Location: SE Iowa
Posts: 157
iTrader: (2)
 
Yeah at first there was one drop, maybe two. I'm really not sure how they got there, but it doesn't seem to be drawing any through the hose. At least not enough to make it run any differently. I ran it again just now with a big looping hose on the vac line to catch gas in it, but nothing. Dry.

Time to pull the carbs for a deep cleaning and maybe rebuild unless there are any other ideas.
FieroGT42 is offline  
post #9 of 11 (permalink) Old 07-19-2013, 10:50 PM
Banned
 
Join Date: Jan 2013
Posts: 2,190
iTrader: (0)
 
You should be able to run the motor on just what is in the fuel bowls, no vacuum line hooked up. Might try that. Long shot, but there should never be fuel in that line ever.
wmsonta is offline  
post #10 of 11 (permalink) Old 07-19-2013, 11:12 PM
Senior Member
 
Join Date: Mar 2012
Posts: 450
iTrader: (0)
 
Garage
An unknown history carbed bike, and then add that it is 26 years old, a carb cleaning is obviously mandatory! Clean it and then start troubleshooting if needed.
Rebel13 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