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Is there a vacuum hose connected to the right side carb (rear cylinder)? I think that's the hose in the last pic, and connects to the valve, also in the last pic under the rear of the tank.

If the other hose is connected beside the radiator cap, then it runs to the coolant reservoir.

Make sure the fuel lines don't have any loops or uphill runs to the carbs. They need to run downward or at least level.
 

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But also for the coolant line you are talking about, not sure where that would connect because the radiator is in the front and the coolant port, not sure where the coolant tank is, thats weird because the tube runs to the back of the bike!
 

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But also for the coolant line you are talking about, not sure where that would connect because the radiator is in the front and the coolant port, not sure where the coolant tank is, thats weird because the tube runs to the back of the bike!
The coolant reservoir is on the right side, between the cylinders, white plastic tank with a black cover.

Up by the radiator, remove the right side neck cover to expose the radiator cap, the same hose would connect just below the radiator cap.

Not sure if that's what the hose is, need to see where the hose runs to.
 

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Hey, I just gave it a check. That long tube that I was talking about runs to the carburetor, not a coolant reservoir... Does that make it easier to figure out?
Yes, it goes on the valve I posted about earlier, if it's on the right side carb. Left carb vac port goes to the center of the petcock.
 

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Ok I get it now, I searched it up on a different form, the vac line for the petcock is a small tube that is on the left of the car, the long tube I can’t figure out is on the top of the carb… no clue still about that long tube
 

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Ok I get it now, I searched it up on a different form, the vac line for the petcock is a small tube that is on the left of the car, the long tube I can’t figure out is on the top of the carb… no clue still about that long tube

Top of the carb is either fuel or vent. The black plastic tubing 90 degree elbow on the carb is the fuel inlet. The aluminum ports pointed straight up are the vents.
 

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Top of the carb is either fuel or vent. The black plastic tubing 90 degree elbow on the carb is the fuel inlet. The aluminum ports pointed straight up are the vents.
So nothing connects to the black plastic on the bottom of the tank, I figured out the top of the carb is vent, I couldn’t find any other forms. You know the petcock right? For the long metal rod where the filter goes on top, is there a way to pull the whole rod out? Or it’s like welded or sealed in there? Because I have a specific petcock for my dads 89” Vulcan that used vaccume, and the air filter sort of broke a piece of plastic off of the filter. I just need to know if I can get that off without reforming the rod, thanks
 

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So nothing connects to the black plastic on the bottom of the tank, I figured out the top of the carb is vent, I couldn’t find any other forms. You know the petcock right? For the long metal rod where the filter goes on top, is there a way to pull the whole rod out? Or it’s like welded or sealed in there? Because I have a specific petcock for my dads 89” Vulcan that used vaccume, and the air filter sort of broke a piece of plastic off of the filter. I just need to know if I can get that off without reforming the rod, thanks
Yes, the filter screen is removable, it presses onto a tube on top of the petcock.
 

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Have you taken apart the ignition switch under the key and cleaned and stretched the springs? I say this because my bike would idle all day but while riding would shut off. Not bumps in the road either. That switch does strange things to the bike.
I just experienced this yesterday. I moved the switch just a tiny bit past where it needed to be. The oil light didn't come on, like it normally does, the neutral light wouldn't come on. The bike would start and idle, but as soon as I got moving, it would die.
I turned the switch off, turned it back on gently and it seemed to fall in the spot it belonged in. All was well after that.
 

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I bought a 2001 Vulcan 750, and it was torn apart. I got it back together and it runs good, but it runs out of gas in about a block. I think the hose that goes to the petcock vacuum fitting which points straight down, is coming from the wrong place. Where is the other end supposed to go? :BLAM:

I sure could use a new petcock, because the screen on the reserve side is broken. If anyone has an extra petcock, I'll buy it from you.
I bought a 2001 Vulcan 750, and it was torn apart. I got it back together and it runs good, but it runs out of gas in about a block. I think the hose that goes to the petcock vacuum fitting which points straight down, is coming from the wrong place. Where is the other end supposed to go? :BLAM:

I sure could use a new petcock, because the screen on the reserve side is broken. If anyone has an extra petcock, I'll buy it from you.
I bought a 2001 Vulcan 750, and it was torn apart. I got it back together and it runs good, but it runs out of gas in about a block. I think the hose that goes to the petcock vacuum fitting which points straight down, is coming from the wrong place. Where is the other end supposed to go? :BLAM:

I sure could use a new petcock, because the screen on the reserve side is broken. If anyone has an extra petcock, I'll buy it fro
 

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I know the solution to this problem with any of the Kawasaki's with this setup. I have a 2009 Vulcan 500 and battled it for awhile. And the cause is the hose passing under the seat and gets compressed on mine. I tried all sorts of things until I finally figured to just cut the part rubber part of line that passes under the seat and replace it with metal brake/automatic transmission line. Not long just the few inches where the problem area is. So you need to find where this is happening on any collapsing rubber hose spot on vacuum assist petcock bikes. At least that's what my fix would be. By the way if you ever notice that there is a problem with either sitting at a light or decelerating to a low speed of freeways etc. I have figured out it has something to do with this system also. More than likely your tank cap is not sealing right etc and you need to clean around cap etc. System sucks you have to constantly figure out WTF it's doing to you.
 

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I bought a 2001 Vulcan 750, and it was torn apart. I got it back together and it runs good, but it runs out of gas in about a block. I think the hose that goes to the petcock vacuum fitting which points straight down, is coming from the wrong place. Where is the other end supposed to go? :BLAM:

I sure could use a new petcock, because the screen on the reserve side is broken. If anyone has an extra petcock, I'll buy it from you.
Got mine from the big a
 

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One comes out to the petcock which of course supplies the vacuum that opens diaphragm in back of petcock. The other is vapor line which goes down with battery overflow tube to ground. In California bikes it goes a canister system setup to be recycled back into combustion. Either your diaphragm is bad (which you can check by renting a vacuum tester from Auto Zone for free). Hook to back of diaphragm hose inlet and start with just a little vacuum and runs if good. And make sure that vacuum line is not getting kinked or smashed like mine. Being a four cylinder it would kick and sputter if it was the cab related before it died. Gas cap problems, cleans the seal and overflow real good. But sounds to me like you just need to run that vapor line down with the battery, buy a diaphragm petcock rebuild kit make sure you give the petcock a scrub down with carb cleaner etc and your set.
 
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