2004 vulcan 500 carb problems. [Archive] - Kawasaki Vulcan Forum : Vulcan Forums

: 2004 vulcan 500 carb problems.


pharoah27
05-13-2011, 02:08 AM
Hello everyone! I have a 2004 vulcan 500 that I bought june of last year. About to be a year and I haven't been able to put 400 miles on it yet. I'm ready to ride it so heres the story...I had owned the bike about 2 weeks and the gas got low, i put it on reserve and went to the store and put gad in it. When I came back from paying for the gas there was gas everywhere under the bike. I found out that it was coming from the overflow tube, apparently there was trash in that tank, so me being mr fix it took the carbs off and cleaned them..(big mistake) the carbs were dirty but before i did that the bike was running fine, after I got through and put the carbs back on the bike was running very bad. Spitting and sputtering. (thats the best way I know to describe the sounds) anyway-I took it to the local kawasaki shop and they were going to rebuild the carbs for me. They called and said that the tank on that bike was off either a 750 or 800 vulcan they were not sure, but that I really needed to buy a new tank from them, and they said they went ahead and rebuilt my carbs the best they could but the carbs were to worn out to be fixed right, and I needed to buy new ones. I didnt have the $800 at the time and told them I couldnt. When I got the bike back it would run fine idling but when you gave it gas at first it would spit and sputter again but then do fine. The furtherest(spell check) i had drove it was about 2 miles. I decided to try it on a drive and went about 10 miles and that thing start spitting and sputtering so bad. Anyone have any ideas what would cause that? Anyone think that dealership was just trying to get money from me? I think that the carbs could be rebuild to run fine because it was running fine before i tried to play mr fix it. I just want to know what you all think? Please keep insults to a minimum, I already feel stupid for trying to fix it and making it worse-(ahah) any advice would be greatly appreciated

Blaine
05-13-2011, 07:51 AM
I think the shop was trying to hose you.My bike is 22 years,and rebuilt the carbs no problem.You need to check to make sure you are getting good fuel flow to the carbs from the tank.The filters in the petcock may be dirty.Also make sure that the over flow tube is open & and away from the intake. I'm assuming that the air box is installed correctly?
:);)

cbkinnc
05-13-2011, 09:52 AM
Do you have a side shot photo of your bike? I would like to see what the tank looks like. I agree with Blaine. Sounds like they are trying to milk you. Check your air filter, vacuum hoses and gas cap vent. If I'm not mistaken, if the tank does not vent, pressure will build up and may cause sputtering. I have heard of the tank vent caps going bad and needing to be replaced.

Leaf
05-13-2011, 10:20 AM
Please keep insults to a minimum, I already feel stupid for trying to fix it and making it worse-(ahah) any advice would be greatly appreciated

Quite the contrary, I applaud your efforts. It is good to see someone taking the initiative to learn to maintain their own bike, something that is sadly all too rare these days. ;P

I'd lean towards thinking it might be a fuel starvation problem. Pull one of your fuel lines to the carbs, stick it in a jar, and turn the petcock to prime. Does the fuel pour out at a good rate? If not, clean the tank and the petcock.

Does the sputtering at higher rpm stop when you have the petcock set to prime? If so, then check the vacuum system for leaks (on main and reserve settings, a positive vacuum is required to open the diaphragm in the petcock and let gas flow, but on prime it's gravity fed).

Barring all that, then I'd be inclined to think that the main jet is a little clogged. Fill up the tank, pour in a half a can of seafoam and see if it clears up.... Maybe you'll get lucky.

pharoah27
05-13-2011, 12:37 PM
Tried to add a picture but can't seem to figure out how. They done something to the petcock valve not sure what but it has something oozing out of it now that is brown and after it dries it's sticky. They were supposed to have rebuilt it, and about the insults leaf---that was mainly me just joking around. I have talked to another shop around here and they told me they would rebuild the carbs and not to expensive either, I am just a little nervous to take it and drop it off at a shop again--it's a little frustrating when you go to a shop pay money and not getting a bike back that is fixed--i'm just ready to get out on the road and ride-ahah

Leaf
05-13-2011, 12:41 PM
Ewwww, tank rust?

That's a real pita to deal with. :<

pharoah27
05-13-2011, 12:50 PM
i'm not sure that it's rust-I think it is something that shop tried to use to seal the petcock instead of rebuilding it like they said. It had this brown stuff all over the petcock valve when I picked it up from the shop-I took the tank off and cleaned it before i took the bike to the shop and there was no rust in it

cbkinnc
05-13-2011, 12:52 PM
"They done something to the petcock valve not sure what but it has something oozing out of it now that is brown and after it dries it's sticky."

That does not sound right.

pharoah27
05-13-2011, 12:57 PM
yea I figured it was just a quick fix they did to save them money

pharoah27
05-13-2011, 01:01 PM
Quite the contrary, I applaud your efforts. It is good to see someone taking the initiative to learn to maintain their own bike, something that is sadly all too rare these days. ;P

I'd lean towards thinking it might be a fuel starvation problem. Pull one of your fuel lines to the carbs, stick it in a jar, and turn the petcock to prime. Does the fuel pour out at a good rate? If not, clean the tank and the petcock.

Does the sputtering at higher rpm stop when you have the petcock set to prime? If so, then check the vacuum system for leaks (on main and reserve settings, a positive vacuum is required to open the diaphragm in the petcock and let gas flow, but on prime it's gravity fed).

Barring all that, then I'd be inclined to think that the main jet is a little clogged. Fill up the tank, pour in a half a can of seafoam and see if it clears up.... Maybe you'll get lucky.



i'm not sure where prime is on the petcock--do any of you know where i can buy a new petcock valve?

Blaine
05-13-2011, 01:02 PM
You need to take the petcock off and see what they done to it before that gunk gets into the carbs.A rebuild kit for the petcock is not too expensive.Also a good idea to install a inline filter when you got things apart.
:);)

pharoah27
05-13-2011, 01:24 PM
You need to take the petcock off and see what they done to it before that gunk gets into the carbs.A rebuild kit for the petcock is not too expensive.Also a good idea to install a inline filter when you got things apart.
:);)
already installed an inline filter. is it hard to rebuild the petcock valve? (On a lighter more happy note) couldn't they have came up with a better name for that valve??? ahah just went and started the bike and it feels like when you open the throttle it feels like it bogs before it revs up, along with the spitting and sputtering

Blaine
05-13-2011, 02:57 PM
already installed an inline filter. is it hard to rebuild the petcock valve? (On a lighter more happy note) couldn't they have came up with a better name for that valve??? ahah just went and started the bike and it feels like when you open the throttle it feels like it bogs before it revs up, along with the spitting and sputtering

The petcock is very easy to rebuild,only a couple of pieces.There are some rebuild kits on e-bay for less than $25.00

:);)

Leaf
05-13-2011, 03:21 PM
Flush that tank out good too. Hard to tell if any of the petcock funk leaked out into the tank.

Don't go to that bike shop anymore! -_-'

Lol.

Motolove
05-13-2011, 04:53 PM
They called and said that the tank on that bike was off either a 750 or 800 vulcan they were not sure, Have you determined if this was correct or not yet?

BetterLife
05-14-2011, 12:39 PM
Just thinking out loud, the tank for a 750 has a different shape than the 800. If your bike had the tank from a 750, they should have noticed that when you dropped it off.

Was the lever on the petcock pointing to the rear of the bike when you were filling the tank?

pharoah27
05-14-2011, 02:06 PM
yea it's true, i asked the guy i got the bike from, and he said it came off a vulcan 750. I took the line off the petcock valve and no gas would flow when the bike wasnt running, but i had the petcock valve on, then i turned the valve to off and gas strted flowing, i guess they put the petcock valve back together backwards, but i wonder how the bike was running when gas wasnt flowing. Can vacum pull gas from the petcock valve? also the tank bolts up good at the front but the bolt hole at the rear doesnt line up-bigger tank, tank doesnt move at all, but the petcock valve is really close to the engine.

Blaine
05-14-2011, 02:30 PM
yea it's true, i asked the guy i got the bike from, and he said it came off a vulcan 750. I took the line off the petcock valve and no gas would flow when the bike wasnt running, but i had the petcock valve on, then i turned the valve to off and gas strted flowing, i guess they put the petcock valve back together backwards, but i wonder how the bike was running when gas wasnt flowing. Can vacum pull gas from the petcock valve? also the tank bolts up good at the front but the bolt hole at the rear doesnt line up-bigger tank, tank doesnt move at all, but the petcock valve is really close to the engine.
The fuel shouldn't flow with the bike not running unless it is in the "prime" position.Vacuum from the engine opens the petcock and allows fuel to flow.A different tank would not affect how the fuel flows,if the petcock is working properly.Are you sure the petcock is flowing fuel in the "off" position and not in the "prime" position?The petcock will have either ["pri" "run" "res"] or ["off" "run" "res"] .It wont have both "pri" and "off".
:);)

PI Robert
05-14-2011, 10:31 PM
What we're calling a fuel tank petcock is listed as a "tap assembly" in the Kawasaki parts catalog. I just bought and installed one.

Something funky is going on with your petcock :snicker: with the brown sticky stuff. That shouldn't be there. The tap assy. (that's the way it's listed) has a gasket that seals the tap's face with the tank. And each mounting bolt has a nylon/plastic washer. If you forget to put the washers on the bolts, it will leak like a sieve when you put the tank back on and put gas back into it. Don't ask how I know :o But there shouldn't be any sealant.

Don't know how this will shake out for you, but I've rebuilt a number of carburetors, and then rebuilt them again when the engine wouldn't run right. It's easy to mess up on one of the steps or get something in wrong. So I'm thinking you may get to join the exclusive carburetor rebuild re-rebuild club. :D

cbkinnc
05-15-2011, 09:08 AM
What we're calling a fuel tank petcock is listed as a "tap assembly" in the Kawasaki parts catalog. I just bought and installed one.

Something funky is going on with your petcock :snicker: with the brown sticky stuff. That shouldn't be there. The tap assy. (that's the way it's listed) has a gasket that seals the tap's face with the tank. And each mounting bolt has a nylon/plastic washer. If you forget to put the washers on the bolts, it will leak like a sieve when you put the tank back on and put gas back into it. Don't ask how I know :o But there shouldn't be any sealant.

Don't know how this will shake out for you, but I've rebuilt a number of carburetors, and then rebuilt them again when the engine wouldn't run right. It's easy to mess up on one of the steps or get something in wrong. So I'm thinking you may get to join the exclusive carburetor rebuild re-rebuild club. :D

I'm a proud member!

XCR600
05-15-2011, 11:17 AM
If your giving it throttle and it bogs it can be too much fuel. Check your plugs if you haven't , if they are black & wet your way too rich, that could mean your carb is dumping too much fuel. Could be the accelerator pump is leaking. Is there gas coming out the carb vent ?

XCR600
05-15-2011, 02:45 PM
With the shop saying the carbs are already worn out tells me they were simply lost. After almost 30 years as an automotive technician the only carbs I couldn't save were the physically broken ones. After the O.P. and the shop has been into them I'd be looking to MAKE ABSOLUTELY CERTAIN everything is exactly back to factory specs inside. Things like jets, needle position, float level, cable adjustment etc, etc, etc. Of course that's after making sure the tank and lines are clear and have adequate fuel flow.

Joe

Totally agree , seems the shop doesn't have the skills to do carb work or just would rather stab you with an expensive and unnecessary replacement. Judging by there makeshift petcock / fuel tap repair they don't seem vary competent. I would still read your plugs to help zero in whats going on in the cylinder's.

Blaine
05-15-2011, 04:58 PM
Could be the accelerator pump is leaking.

Accelerator pump ???????:confused:

XCR600
05-15-2011, 06:42 PM
Accelerator pump ???????:confused:

May be the wrong term for a bike carb ? When you twist the throttle it shoots a stream gas into the throat of the carb.

pharoah27
05-15-2011, 10:03 PM
well i took the spark plugs out yesterday and replaced them with new ones. The old ones were dry and looked kind of white. Didn't really help at all though. I also went to a local guy that sells used bike parts and he had one set of vulcan 500 carbs that needed rebuild-(go figure). I'm thinking that maybe I should just take the bike to the other shop that said they can rebuild the carbs, buy new ones or sell it. Idk what to do-feeling frustrated!

fastpakr
05-15-2011, 11:54 PM
If you're not in a tremendous hurry, I'd be glad to tear the carbs down and clean them out, then mail them back to you. Have an ultrasonic machine here that should help ensure that nothing gets left behind during the cleaning process.

pharoah27
05-17-2011, 02:23 PM
If you're not in a tremendous hurry, I'd be glad to tear the carbs down and clean them out, then mail them back to you. Have an ultrasonic machine here that should help ensure that nothing gets left behind during the cleaning process.



that's very nice of you-how much would that cost me? and, thanks alot-very friendly!

fastpakr
05-17-2011, 02:39 PM
Just whatever it costs to ship each direction. I'd love to see you get this thing on the road (plus any replacement parts if they're actually needed). As fair warning, it might take me a week or so to take care of.

XCR600
06-13-2011, 11:09 PM
Actually a small displacement engine like this can get by with what is pulled from the pilot and main jet when accelerating by negative pressure in the intake tract. No "accelerator pump" is needed or employed in most cases.

Joe

Although I have an 800 my carb does have an accelerator pump and shoots a jet of fuel into the carb throat when you give the throttle a twist or manually actuate the linkage. 1st pic is the orifice the gas is pumped through ( brass color encircled by the gasket low left ) 2nd pic is the pump & linkage , Mikuni's on my sleds also had pumps.

XCR600
06-13-2011, 11:38 PM
We're talking about a 500 problem though. The 800 is a completely different animal.

Joe

Roger that

mjones2002
09-19-2013, 01:11 PM
on my 2008, prime is between on (bottom) and reserve (top). it is labeled PRI.

wallacem
09-24-2013, 11:29 AM
Lever down is "on". lever up is "reserve", lever side ways is "prime".

osceolawell
09-24-2013, 09:52 PM
Yea, my first 500 I changed the oil and filter. I took it for a ride.
When I goy home, turned the bike off and turned the fuel off.
The next day I drained the gas and oil out of the crank case. Changed
the oil filter and added new oil. Now I know that off is prime, not off.
Did I just tell on myself ? It's an old age thing.;)