Gas in all carburators, except one.

[Guest]

After cleaning up and installing a repair kit it I have run into a problem.. There is no fuel in the float bowl in carb 4.
1, 2 and 3 fills up just fine. I removed the bowl and set the petcock on PRE. nothing happens. The vakuum-hose is also in good condition.
Do you have any idea of what could be wrong?

The picture was taken before i took it apart.

[tom203]

Something is blocking fuel... Float stuck, unlikely..... Gunk in passage, more likely. Did you seperate the carbs from each other when you used the "repair kit"?

[runhan90]

Floaters and needle seems to work fine.. Yes, i took them apart and cleaned them separately. Can it have anything to do with the vakuum hose?
I find a lot of information on carburators in here, but its almost always the "never" vakuum types, not the mechanical wich i have.

[Sandy]

Fuel passage is simple and if the float valve is working fuel should flow unless something is blocked. I noticed in the photo your #2 and #4 vent tubes are linked together. These are vent tubes, not vacuum ports and should be open to atmosphere, not hooked together. Probably nothing to do with your problem if you've tested with the float bowl removed but just an observation. Has to be a blockage somewhere.

[runhan90]

Thanks for the reply. I´ll check for blockage tomorow then. hopefully thats it.

Fuel passage is simple and if the float valve is working fuel should flow unless something is blocked. I noticed in the photo your #2 and #4 vent tubes are linked together. These are vent tubes, not vacuum ports and should be open to atmosphere, not hooked together. Probably nothing to do with your problem if you've tested with the float bowl removed but just an observation. Has to be a blockage somewhere.

As I understand it, the vent tubes (not installed in the picture) is supposed to be connected on the bottom of the carb? The tube on Carb 3 is connected to the vacuum port on the petcock.

[allojohn]

As I understand it, the vent tubes (not installed in the picture) is supposed to be connected on the bottom of the carb? The tube on Carb 3 is connected to the vacuum port on the petcock.

No, the tubes on the bottom of the float bowls are for overflow. As Sandy says, the vents on carbs 2 & 4 should be open and run over the airbox.

[Sandy]

Thanks for the reply. I´ll check for blockage tomorow then. hopefully thats it.



As I understand it, the vent tubes (not installed in the picture) is supposed to be connected on the bottom of the carb? The tube on Carb 3 is connected to the vacuum port on the petcock.

No, those are the float bowl overflow tubes. Vacuum on #3 is correct, the same port on #2 and #4 are vent tubes.

EDIT: LOL. No fair, you can type faster.

[allojohn]

EDIT: LOL. No fair, you can type faster.

I saw you were offline, so I jumped in! You must've logged on a minute later....

[hannibal]

Maybe the fuel "line" between 3 and 4 is blocked. It's a pretty large diameter tube, so it's unlikely. Just pointing out that #4 may not be getting fuel at all.

[allojohn]

Maybe the fuel "line" between 3 and 4 is blocked. It's a pretty large diameter tube, so it's unlikely. Just pointing out that #4 may not be getting fuel at all.

Any chance you put the float on upside down? Yes, I have done that and it'll shut the valve very effectively......

[azr]

I bet you have the carb bodies mixed up. When you look at the sides of #1 & #4, inline with where the fuel feeds are on #2 & #3, there is a hole but it is blocked on #1 & #4. If you've mixed up #3 and #4 when you look at #4 there will be a hole there where it should be blocked.........not sure if any of that made sense but it will when you look at your carbs

[runhan90]

Any chance you put the float on upside down? Yes, I have done that and it'll shut the valve very effectively......

hehe its always something easy, so this could be it. Ill check in the morning

[runhan90]

I bet you have the carb bodies mixed up. When you look at the sides of #1 & #4, inline with where the fuel feeds are on #2 & #3, there is a hole but it is blocked on #1 & #4. If you've mixed up #3 and #4 when you look at #4 there will be a hole there where it should be blocked.........not sure if any of that made sense but it will when you look at your carbs

I did not even think of it. Even though i marked them, the marking goes away while washing them. Thanks for the response, ill check tomorrow

[runhan90]

All four is now working. I decided to clean the 4th carburator again, and that did the trick. Thanks for the help

[tkent02]

It's a completely simple part of the carburetor, vacuum has nothing to do with it if fuel is getting past the petcock at all. A pipe comes across from #3, then there's the float and it's valve. That's all there is. Sometimes the float gets caught up on an aftermarket or home made gasket, but usually that makes it keep flowing to the top of the float bowl and right on out the overflow tubes at the bottom. Could also be a float just got stuck in some goo in the bowl, but again that tends to hold the float down and make it keep flowing. Take it apart and see what's blocked, let us know what you find out.