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I have a 2003 carbureted Dyna Wide Glide. I overhauled the carb and it would not start. It take long to figure out that there is no fuel going to the carb. The petcock is on, and there is plenty of fuel in the tank. Isn't this supposed to be a simple gravity feed to the carb? What could possibly be blocking the fuel from feeding the carb? I have had it in a short storage but only about a year. Help please.
 

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weird member
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The petcock is vacuum operated, make sure the vacuum line is connected to it.
Can't tell you how many times I've done work and forgot to hook up that vacuum line.

Definitely check this first. This has been the culprit EVERY time for me. That or forgetting to hook the spark plug wires back up.
 
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Sprinkle a small amount of gas in the carb body to help get the whole process going quicker. Vacuum will happen much faster with a running engine even if just for a couple seconds.
 

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This is all great advise and highly appreciated. I did not realize that it was vacuum actuated. I was wondering how you get a vacuum going when you can't get the engine running. I will try what RJ64 suggested.
 

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I shot fuel down the carb and it start immediately then dies. I did that about thirty times with no luck. There is no fuel getting to the accelerator pump.
 

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Just Ride
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Turn petcock to reserve,it doesn't require vacuum.
 

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Check that the small vacuum hose is attached to the back of the petcock. Then backtrack that hose to the VOES module and from there to the vacuum fitting on top of the carb.
A faulty vacuum line will make the bike feel like it's running out of gas. Even a pin hole in that hose will cause issues.
 
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My old carbed ultra didn't need it,that was 1994.
 

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The stock Harley petcock that's vacuum operated, if not modified, has a spring and diaphragm inside that cuts all fuel from flowing through it regardless of whether it's on "run" or "reserve".

The only difference between run and reserve is which hole the fuel comes down from the tank. If you pull the petcock and filter screen, remove the filter screen there's two holes, one of which has a tube coming up. That side with the tube is the "run" side, the side without the tube is the "reserve" side. The petcock valve has an offset hole so that the hole is in alignment with one side or the other, that's why "run" and "reserve" are 180° from each other. Either way, to get to that valve, gas has to get through the diaphragm.

As to the carburetor, the Harley/Keihin CV carb, the accelerator pump doesn't just run or go. If you have fuel in the carb and float bowl, when you twist the throttle from 0 to open the throttle plate, a piece of metal pushes in against a diaphragm to squirt fuel through the accelerator pump jet. Even if the accel pump isn't functioning, the bike should still run as long as fuel is getting to the carb (you'll just have piss poor acceleration).

Now, the float bowl has to be getting gas to it for the accelerator pump to get gas. If the carb bowl is empty or near empty, there's no gas to refill the accelerator pump for it to function. If your carb was completely empty, but has been refilled, you might have to blip the throttle once or twice to prime the accel pump before it squirts. If fuel isn't getting to the pump, it's because it either isn't getting to the bowl or is clogged. If gas is getting to the accelerator pump and it isn't pumping, the accel diaphragm is bad.

So, check your fuel filter screen. If it's clogged up bad, that'll be an issue. The petcock is a pretty simple thing, if there's nothing clogging the valve hole inside and the diaphragm is good, then the issue isn't the petcock. If the diaphragm fails, all that will happen is gas will leak at the petcock (once the carb is full, the float stops more gas from entering the carb, assuming all of that is functioning correctly). As long as the petcock isn't clogged, that isn't going to be the issue. Other than clogging, failures there will result in gas leaking, not stopping.

You said you overhauled the carb. OK is the carb bowl not getting any gas at all? One other possible issue is the float bowl and float needle. You didn't accidentally bump or mash the float, did you (bending the float tab resulting in the float needle remaining closed or becoming damaged)?

As Schmidty said though, check that whole vacuum line. It's fully pressed onto the back of the carb, right?

The line should go from the vacuum fitting on the back carburetor to a T piece where one side goes to the VOES and the other to the petcock, generally speaking.
 

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Many of these suggestion will be helpful i'm sure. If it was me with this ethanol gas nowadays the first thing i would do is drain ALL old gas out from every possible location. Put fresh gas in there. See, it only takes a month or two for the junk ethanol gas to start separating. When it separates much damage can be done to fuel lines, carbs, etc. Anytime gas is going to sit for as long as you say this has, Startron (not Stabil) is the only stabilizer that properly sets your gas up so it will not separate. It can be found at Tractor Supply, Walmart, Northern Tool, maybe some others.
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I have a 2003 carbureted Dyna Wide Glide. I overhauled the carb and it would not start. It take long to figure out that there is no fuel going to the carb. The petcock is on, and there is plenty of fuel in the tank. Isn't this supposed to be a simple gravity feed to the carb? What could possibly be blocking the fuel from feeding the carb? I have had it in a short storage but only about a year. Help please.
I have a 2003 RK w/carb and would like to know if any of the suggestions resolved your issue.
 

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Discussion Starter #17
I am awaiting a new petcock and will let you know if it solves the issue. Thank you all for your time and thoughtful consideration.
 

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So, check your fuel filter screen. If it's clogged up bad, that'll be an issue. The petcock is a pretty simple thing, if there's nothing clogging the valve hole inside and the diaphragm is good, then the issue isn't the petcock. If the diaphragm fails, all that will happen is gas will leak at the petcock (once the carb is full, the float stops more gas from entering the carb, assuming all of that is functioning correctly). As long as the petcock isn't clogged, that isn't going to be the issue. Other than clogging, failures there will result in gas leaking, not stopping.

You said you overhauled the carb. OK is the carb bowl not getting any gas at all? One other possible issue is the float bowl and float needle. You didn't accidentally bump or mash the float, did you (bending the float tab resulting in the float needle remaining closed or becoming damaged)?
All GREAT points Kyle, This part i highlighted is exactly what i was thinking: When overhauling a carb, it is really easy to mess up the float settings.. Been there many times! The Factory Service Manual has a very good description on how to adjust the float properly... As stated, the bike was in storage for a year. If that float bowl wasn't drained prior to storage. That Float and needle are going to stick good! No amount of carb spray will free that up. That little tab on the float is a touchy character... If the float bowl won't fill, the diaphragm will never get the fuel to squirt. I can only assume the OP has checked the fuel lines for kinks... Just the obvious stuff that i have been bitten by...
 
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