94 vulcan spewing gas from carbureator vacume line - Kawasaki Vulcan Forum : Vulcan Forums
» Insurance
» Sponsors
Go Back   Kawasaki Vulcan Forum : Vulcan Forums > Motorcycle Models > Vulcan 1500

Reply
 
Thread Tools Display Modes
Old 12-05-2012, 07:14 PM   #1
sean
Junior Member
 
Join Date: Nov 2012
Location: knoxville tennessee
Posts: 21
Default 94 vulcan spewing gas from carbureator vacume line

Been trying to get this old bike running right and noticed the gas shoots from the lines going from the carb to the vent assembly attached under the gas tank. I tried leaning out the adjusters on the carb but it seems to get worse. Its almost like the hoses comming up from the carb constantly have gas in them and if i run the vent hoses away from the gas tank and hold them straight up the bike runs better. Weird problem which i'm guessing has to do with stuck floats or something like that? Anyone run into this before?
sean is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 12-06-2012, 06:32 PM   #2
sfair
Top Contributor
 
Join Date: Apr 2009
Posts: 7,767
Default

Quote:
Originally Posted by sean View Post
i'm guessing has to do with stuck floats or something like that?
I think your guess is a strong lilelyhood.
I can see a carb teardown, clean and inspection in your future.
sfair is offline   Reply With Quote
Old 12-09-2012, 05:50 PM   #3
sean
Junior Member
 
Join Date: Nov 2012
Location: knoxville tennessee
Posts: 21
Default 94 vulcan gas runs out under bike after hard acceleration

So i tore the carbs off and separated them. What i discovered in the right side bowl was the float valve was stuck in the down position. I removed it seen some oxidation if you call it that on the side of it so cleaned it with some steel wool and reattached the bowl to it and worked it by hand and it seemed fine. While i was at it i took everything else apart and noticed also on the right carb the coasting enricher seemed to have gas on both sides of the rubber stopper but not on the left side. Cleaned everything and also noticed the jet on the left carb says 112 on it and the right side says 115 on it and not sure if that affects anything or not. Put it back on today and started it up after a long series of full choke it fired up and rumbled rough for a few then started idling without choke. I adjusted the idle screws out 2 turns and let it run for awhile. It sounded like a spurting from the right side which i narrowed down to the vacume port above the output of the right carb. It is pulsing/spitting air out of it but not doing it on the left side. Took it out for a ride and really got on it to wind it out and it still had a bit of a hickup but felt pretty strong. Drove it back to the house and when i started pulling in i started to smell gas. Parked it and seen gas comming from the carb bowl vent hoses running under the bike so i'm thinking stuck float valve after letting off the throttle at high RPM cause i came in screaming and really gassed it hard when i pulled in. Anyone who reads this and has any thoughts let me know as i am going to pull carb once again (3rd time). Anyone think the vacume pulse is from a leaky intake or exhaust valve causing air to come back thru the carb? It's about the only explaination i have at this point.
sean is offline   Reply With Quote
Old 12-09-2012, 05:55 PM   #4
sean
Junior Member
 
Join Date: Nov 2012
Location: knoxville tennessee
Posts: 21
Default

this a 1994 vulcan vn1500
sean is offline   Reply With Quote
Old 12-09-2012, 07:32 PM   #5
sfair
Top Contributor
 
Join Date: Apr 2009
Posts: 7,767
Default

If you have gas coming from bowl vents, then flooding is occuring and it must be fixed first before any other problems can be addressed. Bowl fuel level is critical for correct carb operation.
You could still have a sticky float, a float that is a sinker, dirty needle and seat, needle and seat that is worn and no longer doing its job.
If a carb floods as you describe, you can and will find gas in many places it does not belong, so this is the first problem to tackle.

Post back with questions and results.
sfair is offline   Reply With Quote
Old 12-23-2012, 09:00 AM   #6
sean
Junior Member
 
Join Date: Nov 2012
Location: knoxville tennessee
Posts: 21
Default 94 vulcan 1500 backfire

i removed the carbs and set the floats higher by bending the metal tang on each float. i reinstalled the carbs and now it is running much better but i am getting an intermittent pop (backfire at idle) when i wind it up it is a little hessitant ( hickups and pops) until i hit a good cruising speed about 3/4 throttle but then if i let off the throttle and get back on it she really sputters and backfires. I can tell the backfire is comming from the front jug as the carb jumped right out of the rubber boot when i was sitting still and reving it up. I reattached the boots to the carb thinking maybe the clamps were loose letting air in but i still get backfiring. I removed the air valves and plugged the ports on the engine as instructed in other forums they call it marbling but i just took out the air valves and and removed the hoses attached to engine and found a brass water line cap at lowes and soldered it on to it. After removing the air valves there are 2 ports on the carb that have vaccume lines with nothing on them now. After realizing how gas has played a huge part of getting this thing tuned i wonder if the jet sizes are now incorrect as i have read up on that and my jet sizes are 42 for the idle and 112 for the main but i can't find a diagram or chart showing what size you should have with stock exhaust and plugged off emmision air valves. i also wonder if its the engine timing set incorectly by the prvious owner or a burned (faulty) engine valve sticking open letting air back thru the intake valve on the exhaust stroke when it should be going out the exhaust valve or that cylander haveing low compression and not eginiting properly on the compression stroke. I think its time to throw in the towel and remove the motor and tear it down unless anyone else thinks its still carburetor related?
sean is offline   Reply With Quote
Old 12-23-2012, 09:16 AM   #7
sean
Junior Member
 
Join Date: Nov 2012
Location: knoxville tennessee
Posts: 21
Default 94 vulcan backfire parts replaced during initial diagnosis

here are the parts i replaced from kawasaki brand new, i replaced the coils, wires and spark plugs, rubber intake boots for both carbs, engine oil, filter and screen, battery. Tried seafoam in the tank and have drained filled the gas tank numerous times to rule out bad gas. Air filters are clean and installed air box assembly as stock.
sean is offline   Reply With Quote
Old 12-24-2012, 06:31 AM   #8
Bear2123
Top Contributor
 
Bear2123's Avatar
 
Join Date: Oct 2011
Location: SW Chicago suburbs
Posts: 4,477
Default carb

Quote:
Originally Posted by sean View Post
i removed the carbs and set the floats higher by bending the metal tang on each float. i reinstalled the carbs and now it is running much better but i am getting an intermittent pop (backfire at idle) when i wind it up it is a little hessitant ( hickups and pops) until i hit a good cruising speed about 3/4 throttle but then if i let off the throttle and get back on it she really sputters and backfires. I can tell the backfire is comming from the front jug as the carb jumped right out of the rubber boot when i was sitting still and reving it up. I reattached the boots to the carb thinking maybe the clamps were loose letting air in but i still get backfiring. I removed the air valves and plugged the ports on the engine as instructed in other forums they call it marbling but i just took out the air valves and and removed the hoses attached to engine and found a brass water line cap at lowes and soldered it on to it. After removing the air valves there are 2 ports on the carb that have vaccume lines with nothing on them now. After realizing how gas has played a huge part of getting this thing tuned i wonder if the jet sizes are now incorrect as i have read up on that and my jet sizes are 42 for the idle and 112 for the main but i can't find a diagram or chart showing what size you should have with stock exhaust and plugged off emmision air valves. i also wonder if its the engine timing set incorectly by the prvious owner or a burned (faulty) engine valve sticking open letting air back thru the intake valve on the exhaust stroke when it should be going out the exhaust valve or that cylander haveing low compression and not eginiting properly on the compression stroke. I think its time to throw in the towel and remove the motor and tear it down unless anyone else thinks its still carburetor related?
Might consider a compression test, or better yet a cylinder leak down test. Those will tell you if the valves are truely seating properly.
Bear2123 is offline   Reply With Quote
Old 12-24-2012, 12:44 PM   #9
sfair
Top Contributor
 
Join Date: Apr 2009
Posts: 7,767
Default

I think you have carb problems, not valve problems. (not yet anyways)
The carbs have to be torn down to the last item, cleaned, inspected and any suspect parts replaced. Adjustments MUST be made BY THE BOOK, or it will never run correctly. That includes float level and sync.
Once that is done, check for vacuum leaks and correct hose routing.

How many miles on it?
sfair is offline   Reply With Quote
Old 12-26-2012, 01:16 PM   #10
sean
Junior Member
 
Join Date: Nov 2012
Location: knoxville tennessee
Posts: 21
Default 94 vulcan vn1500

Bike has 43,000 original miles and i notice non factory gasket sealant around the valve cover and head areas as if the PO had it apart for repairs. I agree it seems its still carb related or could simply use new floats, needles, float vavles and jets coasting enricher diaphrams etc. I wonder if anyone knows of a decent recomended place to buy these? The dealer is a little pricy for whats seems to be standard carb components not specific to just a kawasaki motorcycle. Also i tried bypassing the fuel pump just for kicks to see if it changed anything and the bike ran exactly the same. The fuel pump is pumping but very low pressure as the book states and thinking its possible under load it is starving the carb due to being weak.
sean is offline   Reply With Quote
Sponsored Links
Advertisement
 
Reply

Thread Tools
Display Modes

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

Forum Jump

Powered by vBadvanced CMPS v3.2.2

All times are GMT -5. The time now is 09:15 PM.


Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Garage Plus vBulletin Plugins by Drive Thru Online, Inc.
Motorcycle News, Videos and Reviews
Honda Grom Forum Harley Davidson Forum Honda 600RR Forum Kawasaki Forum Yamaha R6 Forum Yamaha FZ-09 Forum
1199 Panigale Forum Roadglide Forum Honda CBR1000 Forum Vulcan Forum Yamaha R1 Forum Yamaha R3 Forum
Ducati Monster Forum Harley Forums Honda CBR250R Forum ZX10R Forum Star Raider Forum Yamaha Viking Forum
Suzuki GSXR Forum V-Rod Forums Honda Shadow Forum Kawasaki Motorcycle Forum Star Warrior Forum KTM Duke 390 Forum
SV650 Forum BMW S1000RR Forum Honda Fury Forum Kawasaki Versys Forum Drag Racing Forum Ducati 899 Panigale Forum
Suzuki V-Strom BMW K1600 Triumph Forum Victory Forums Sportbikes BMW NineT Forum
Volusia Forum BMW F800 Forum Triumph 675 Forum MV Agusta Forum HD Street Forum Suzuki GW250 Forum
Yamaha Motorcycles Victory Gunner Forum Honda Vultus Forum HD LiveWire Forum Ninja H2 Forum Ducati Scrambler Forum Kawasaki Ninja 250SL Forum