Gas Tank Vents, Fuel Petcock - 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 3 (permalink) Old 08-08-2017, 04:58 PM Thread Starter
Junior Member
Join Date: Aug 2017
Posts: 2
iTrader: (0)
Gas Tank Vents, Fuel Petcock


Well as you can probably guess I am a newbie to the Vulcan World.
I bought a 1998 VN 750 two years ago and never really got the opportunity to ride due to life. I always started it and removed the battery over winter and kept it in the garage.
I took out to show to a guy who wanted to buy it and and it wouldn't stay running in idle. I thought the gas might be the issue it being old. I rode to the gas station and filled it up added a can of gas treatment thinking I would drain the tank in the morning and flush it out as well.
While removing the tank I found the two vent hoses on the back of the gas tank were not connected to anything. where to they normally connect to ?
Also I took the tank off and attached hoses to the gas valve and turned on the petcock and no gas comes out the petcock no matter what position it is in On or RES or even off is this normal does the gas tank require a vacuum for the petcock to work?
Any advice or direction would be greatly appreciated
JoelB is offline  
Sponsored Links
post #2 of 3 (permalink) Old 08-08-2017, 05:43 PM
Senior Member
ubertalldude's Avatar
Join Date: Jun 2016
Location: NE Florida
Posts: 719
iTrader: (0)
vent tubes at the back aren't supposed to go anywhere, those are fine. the petcock is vacuum actuated, so it won't flow fuel until the engine runs. sounds like the carburetors are gummed up and may need to be cleaned given how much the bike has sat

Earshave+Rejet (38/135) – NGK Iridiums – MCCT Conversion – Slipstreamer S03 Windshield – Custom Extended Backrest – Custom Highway Bars – MOSFET R/R – LED Underglow – Volt+USB In-Dash – Two-Wire & Blue-Wire Mod – Satin Black Engine Paint – Dampers Parts - Jets: Main=99101-393(#132 stock)/Pilot=n424-22 Pilot(#38 stock)
ubertalldude is offline  
post #3 of 3 (permalink) Old 08-08-2017, 07:01 PM Thread Starter
Junior Member
Join Date: Aug 2017
Posts: 2
iTrader: (0)
Thank you
I found away to actuate the petcock and drain the fuel.
I also found a diagram on the fender showing where the blue line is connected to the return pump and there is a open port with a blue dot,
The same diagram shows the red line connecting to a side port on the return pump problem with that there is no open port the the return pump.
So, do you think I should cap the open port on the return pump run the vent lines straight down and open.

Easy enough, now for the carbs the bike sat for a year run occasionally to keep up the battery and move the oil around and such.
I guess I will ask is there a hassle free way to clean up the carbs without removing them,
JoelB is offline  
Sponsored Links


Quick Reply

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:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


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