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My fuel problem continues.

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Mike

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I installed the new Weber and I also installed a new fuel pump rated at 2.5-3 psi. The engine sputters and will sometime run for a moment. My new plugs are black and wet with gas so I am assuming I getting to much gas thru the carb. Could this be a needed float adjustment or a need for a lower volume needle jet in the carb? Is my volume to high on this Weber DGV? I am still novice, although I am learning as It seems like I have replaced about every component on my car, so your comments are very appreciated. Thanks for the help

Mike
1958 Bugeye Sprite
1275 series A
 
Float level, crud in the needle/seat, Gross(e) jets?

What's the pump? Facet, SU, Carter?
 
The fuel pump is a MR Gasket Company 42S, shows no more than 3 psi. I have a clear filter after the pump and I can see fuel flow. On the Weber, I see no outside adjustment for the jets other than the air mixture screw which has a spring behind it. The gas is a coupe weeks old. This morning it didn't even want to sputter. I have cleaned the contacts in the distributer. Oddly enough, considering the problem, I got it stated right away when I installed the carb. It seem to run okay. It wasn't until the following morning that I stated having the sputtering problem. Like I said in the previous post, the plugs are black and wet. I'm new to taking apart a carburetor, Should I dismantle and take it apart to check for crud? I'm not sure what needle jets it has. With such a low output fuel pump, should I put a regulator on it?
Thanks,

Mike
 
I'd say get a cheap pressure gauge on the supply side to SEE what the pressure is first. If it's actually below 3.5 no regulator needed.

Float level may be high, there could be "schmutz" on the seat of the float needle.
 
This is eerily similar to my problem. Replaced and verified everything, fuel output, new regulator (Holley), rebuilt carb, checked all jetting and idle circuit, checked and confirmed float level (all per the Weber spec sheet). Still no workie. It idles great, but once you start to move the accelerator linkage, it just wants to cut-out.

I think I'll put the HS2s back on and go with them. At least the car was drivable at that point. I'm not real pleased with the Weber at all. I thought this would be a simple carb to work on and give the performance boost, but I'm sadly disappointed. I'll follow your progress, Mike. Maybe we can figure it out for both of us.
 
From what you just posted, yours sounds like an accelerator pump issue, Edward. Not sure about Mike's yet.
 
Removed the top of the Weber, no smudge. I need to figure out the float travel. It appears to continue to move upward (additional play) past the point when the valve closes. The Weber instruction say to have no more than 10 mm. What I find interesting is that the orifice at the needle valve right above the spring loaded valve does not close up all the way when I move the float all the way up. Should it? Remember guys, this is my first go around taking apart a carb. I would think that the settings should be correct from the factory on this new weber, maybe not. I'll get a pressure gauge and try that next. Also the bowl was a little less than half full of fuel when I pulled he carb top off.

Mike
 
Removed the top of the Weber, no smudge. I need to figure out the float travel. It appears to continue to move upward (additional play) past the point when the valve closes. The Weber instruction say to have no more than 10 mm. What I find interesting is that the orifice at the needle valve right above the spring loaded valve does not close up all the way when I move the float all the way up. Should it? Remember guys, this is my first go around taking apart a carb. I would think that the settings should be correct from the factory on this new weber, maybe not. I'll get a pressure gauge and try that next. Also the bowl was a little less than half full of fuel when I pulled he carb top off. Should I try smaller jets while I have it apart?

Thanks,

Mike
 
We need to get you some diagrams... the float height is adjusted at the point when the tang for the needle JUST TOUCHES the thing. There is a ball and spring in the needle which will allow the float to move a *bit* further before it makes hard contact. Holding the carb top so the float hangs vertically from the hinge will allow you to be accurate in measuring the point of contact.

Have you a way of taking/posting pix of what you have?
 
Addendum: If you gently blow into the supply port of the carb top as you gently raise the float it should block your pressure at the point when the float is at the 10MM height. Cleaning the area a bit before you blow thru it is helpful, too. :wink:
 
Here's my weber:

DSC_0353.jpg


Mike
 
Does it block your attempt to blow into the supply line as the float hits the 10MM point?
 
It appears as if i have about 16-17 mm of movement before the valve closes. I am measuring from the bottom corner of the float.

Mike
 
99% of carburation problems are electical!!! Could it be condenser??? Coil???
KA
 
The clearance between the carb lid and top of the float should be the 10MM spec'd in the kits. Not certain about the DG series but the DCOE is measured with the gasket on the top of the carb.
 
Nomad: I replaced the coil. I guess the next place to start after making sure the float has a proper adjustment is the distributor area.

Has anyone had to change out the jets to a smaller size? A friend of my suggested going down two sizes.


DrEntropy: The Weber bowl float is a bit goofy. The diagram shows the 10 mm adjustment from the bottom of the float and 51 mm from the bottom to top. The float they show is rounded out the bottom, mine is rectangular.
DSC_0356.jpg




Mike
 
That ~IS~ a bit goofy. Try checking it while hung like this, the contact on the needle nubbin JUST touching:
 
Okay, the measurement is 15.8 mm which would mean that I'm getting to much fuel in the bowl or not enough? Is this enough to cause my problem?

Thanks,

Mike
 
The red reading is 15.8?
That's too low.
However, if the circled 41 (with note for 35/plastic float) is 15.8, yes, too high float and fuel level.
 
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