Petcock Problem - Kawasaki Vulcan Forum : Vulcan Forums
  • 1 Post By vulcandoc
LinkBack Thread Tools Display Modes
post #1 of 4 (permalink) Old 07-17-2018, 05:18 AM Thread Starter
Junior Member
Join Date: Jul 2018
Posts: 4
Petcock Problem

The petcock on my '98 vn800 seems to have a problem. The last few days the bike has been running very rich. It actually cut out 10 miles from home and wouldn't restart. I removed the air filter cover and there was fuel in the airbox. I cleaned it up and let it sit a while and was able to start it, but it didn't run well and idle was very slow. I managed to get home, but it would not idle. I have checked the vacuum line and it seems to be OK. I thought it may have been a stuck float, so I changed the position of the 'selector' from ON to RES and it seems to be running OK in that position. So I think the problem is the petcock. I also noticed that when the 'selector' is in the PRIME position there is a slight leak from the front of the petcock, but this is ONLY when on PRIME. It seems like some maintenance is needed, but I don't know what? I guess the leak can be stopped with a replacement 'O' ring, but what do I do to stop it 'flooding' the carb when it's in the ON position? Help!
Attached Thumbnails
Click image for larger version

Name:	petcock 1.jpg
Views:	42
Size:	70.4 KB
ID:	223344  

Last edited by BadBadger; 07-17-2018 at 05:29 AM.
BadBadger is offline  
Sponsored Links
post #2 of 4 (permalink) Old 07-17-2018, 07:17 AM
Top Contributor
Join Date: Aug 2012
Location: St Paul, MN
Year/Make/Model: 1995 Kawasaki Vulcan 500
Color: Black / grey
Gender: Male
Posts: 625
The petcock allows fuel to flow from the tank into the carb.
If the carb is leaking into the engine it is most likely not the petcock.
The ability of the petcock to seal off the fuel when the motor isnt running is a petock problem.
BUT if the carb dumps fuel into the engine, the float is most likely the problem.

Turn petcock to off.
Remove the fuel line from the petcock to the carb.
Turn petcock to on.
If there is no flow the petcock is holding like it should.

Attach a hose to the carb and fill it with fuel if the carb can hold back the fuel the floats and needle and seat are working.
glhadiator likes this.

To view links or images in signatures your post count must be 1 or greater. You currently have 0 posts.
1995 en500 stock with windshield - 30,000 miles
To view links or images in signatures your post count must be 1 or greater. You currently have 0 posts.
vulcandoc is online now  
post #3 of 4 (permalink) Old 07-23-2018, 07:41 PM
oldrockr's Avatar
Join Date: Sep 2010
Location: Lancaster, PA
Posts: 35
I had a similar problem and found it was caused by corrosion on the float pivot pin.


'96 VN800A
V & H Cruzers
F & S Sissy Bar
Unik Fork Bag
oldrockr is offline  
post #4 of 4 (permalink) Old 07-30-2018, 02:05 PM
Senior Member
texasgrape's Avatar
Join Date: Jan 2015
Location: A stone's throw from Luckenbach, TX
Year/Make/Model: 1996 Kawasaki Vulcan 800 Classic
Displacement/CC's: 800
Color: Blue-Green
Gender: Male
Posts: 330
A faulty petcock and a leaking float valve can indeed be related if fuel is getting into the air filter; Gents it seems we have already had this discussion whereas sfair gave us a schooling on a petcock leaking and the float valve being unable to hold back the fuel at all times; Do the test as vulcandoc suggested; if fuel comes out the petcock in ON or RES then the petcock is bad; replace it; and if not then its the carb; simple test

1996 Vulcan 800, Blue/Green
JUST SOLD: 2016 Indian Scout, Black
SOLD LAST YEAR: 2006 Triumph Rocket III, Black
SOLD LAST YEAR: 1967 Honda 305 Dream, Black

"Going up the country . . . "
texasgrape is offline  
Sponsored Links

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

Similar Threads
Thread Thread Starter Forum Replies Last Post
800 petcock prime my problem? btom Vulcan 800 5 07-10-2016 01:35 PM
Fuel Tap Problem - Petcock Problem Brewster_440 Vulcan 800 0 04-11-2014 08:46 PM
Problem with a Petcock... Dirty_D Vulcan 800 9 01-08-2014 02:18 AM
750 petcock cappy Engine Work 0 07-12-2009 08:26 PM
Wtb: Petcock For En500 MetallHed Wanted to buy or trade Items 0 04-30-2009 04:54 PM

Posting Rules  
You may not post new threads
You may not 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