Vulcan 800 shuts off when I hit gas

[veshchev]

Hi. My 2001 Vulcan 800 dies when I hit gas. It runs with a choke fine. I just got a carb cleaned. Everything looks spotless. What would you recommend to check out? I believe the carb causes this problem. What can it be there? Float level? Wrong mix? What jet is responsible for it? Thanks in advance

[rsterren]

dont have a clue, but i asked for help in the cruiser subforum!

[rustygunner]

OK, need a bit more info so we can help you out.
Was the bike running before you had the carb cleaned? I am assuming you took the carb to a shop and had it soaked? Does the carb have the stock jetting still?
Sounds like the idle A/F mixture is set wrong for starters. You'll have to locate the idle A/F mixture screw on the bottom of the carb. Turn it all the way in until it is seated gently, then back it out 2 1/2 turns. You'll have to remove the airbox and get to it with a small screwdriver, but the carb can (and should) stay on the bike.

[veshchev]

I took the carb to a shop few week ago. It was running ok for a week. Then it started leaking gas (bad petcock maybe). So I rebuild it, replaced a float bowl gasket, and a broken acceleration diaphragm (nobody noticed that before?). Put everything together - dos not accelerate - stalls. Yesterday I spent whole day trying to figure out what and where is wrong. A/F screw is ok. By the way I cant adjust it without taking the carb out since it is on the opposite side - close to the engine. It idles fine. What I noticed: when I spray start up fluid somewhere on the intake manifold, vacuum pipes and etc the engines slowly shuts off. Tried to tighten all up- the same. It is hard to tell where the leak is (if any). Ideas? Thanks for replying.

[rsterren]

hmm, idle?
It idles fine he says.
or am i thinking wrong (again )

[rsterren]

Where did the gas leak from?
might be a stuck float....

[rustygunner]

Float sticking is a problem with the 800's. That probably was the cause of the fuel leak you had.
So you are saying that it idles fine... without the choke pulled out?

[rustygunner]

Might check the needle holder in the carb 'slide' to be sure one of the five plastic 'feet' isn't blocking the slide vent hole too. Happens (don't ask how I know).
Crap, have to work... I'll be back.

[veshchev]

Also: is it possible that an air pump is bad? What is it supposed to do?

[rsterren]

there is no airpump.
but hey, maye the intake is clogged!

take the tank off, en there you'l find the airbox, with a hole.
or try running without the airfiltercover.

[veshchev]

it starts right up with choke, idles fine without. When I hit on gas with choke it accelerates but it is not stable - like it is missing something. Put original spark plugs just to try - the same. The slide vent hole is not blocked - made sure. It is not leaking gas - I took the float out and checked the float needle-almost perfect. The petcock diaphragm was not in great shape- replaced along with another one. Anyway it is not it. Hrrr. Does an intake manifold have to be perfectly tight? How bad does it have to leak so it does not let the engine work?

[veshchev]

tried to run without the airbox and air filter cover - the same. I called an airopump that thing that connects a vacuum lines from the engine, petcock, and the carb...

[rustygunner]

Yea, we usually take the air valve thingy off and cap the lines and nipples on the valve covers.

[rustygunner]

If the carb boot is too tight, it will leak. Definately check for vaccuum leaks. Does the slide come up when you open the throttle? (watch your face and put some safety glasses on... yea, happened to me once; flaming carb fart right in the face )

[veshchev]

well should i release the carb boot clips to make it less tight? When I run it without choke and put a little gas the slide tries to move up - it kinda shakes up and then everything dies. What is the way to check for leaks? Some guy told me to try an electric take around the boot as a temp solution to see if it fixes it....?

[rustygunner]

You could try that. They don't need to be very tight. Too loose will leak as well, but overtightening will cause the rubber to deform and leak. I've done it...

[rustygunner]

Something is not right when it comes off the idle circuit then. Will it run WOT? Don't let is rev because that's really bad on the engine, but just crank the throttle all the way open for a quarter second. Does it die?

[rustygunner]

You may have gotten a small piece of fuel line in the carb when you re-connected the petcock... happens quite a lot.

[rustygunner]

Dude... just thought of something; is the needle holder in upside down??? Someone here did that and that's what happened. Bike wouldn't run off idle.

[snardle]

Originally Posted by rustygunner

OK, need a bit more info so we can help you out.
Was the bike running before you had the carb cleaned? I am assuming you took the carb to a shop and had it soaked? Does the carb have the stock jetting still?
Sounds like the idle A/F mixture is set wrong for starters. You'll have to locate the idle A/F mixture screw on the bottom of the carb. Turn it all the way in until it is seated gently, then back it out 2 1/2 turns. You'll have to remove the airbox and get to it with a small screwdriver, but the carb can (and should) stay on the bike.

Sounds right to me.