Novak Conversions Jeep Wrangler YJ shifters

Weber headache

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GregMP

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So, my recently acquired 1990 yj hasn't driven in 16 years. It has a Weber 32/36 carb, that I did a rebuild on.
Now my headache is to get it dialed in to idle and run right. On line tutorials have you bottom out the air/fuel mix screw and turn out approximately 2 turns.
Then to tweak it, tun it in until it starts to run rough. I turn the screw on mine all the way in, and it never faulters. I'd feel better if is began to stall or quit. But, turning the screw in pretty much has no effect. What else is happening here?
Thanks.
 
did you soak it in carb cleaner, after all those years, it may be still plug up. your adjustment are close to right on starting to get to run.
 
I did soak it, un-conventionally. Two days immersed in Pine-Sol. Flushed it out, baked it dry, re-assembled. Now, just trying to dial it in.
 
I just learned something, I have never used pine-sol for auto parts, i done some research and it used often. thanks for infor. keep working with the idle slowly and i bet you will get it running right. thanks
 
GregMP said:
So, my recently acquired 1990 yj hasn't driven in 16 years. It has a Weber 32/36 carb, that I did a rebuild on.
Now my headache is to get it dialed in to idle and run right. On line tutorials have you bottom out the air/fuel mix screw and turn out approximately 2 turns.
Then to tweak it, tun it in until it starts to run rough. I turn the screw on mine all the way in, and it never faulters. I'd feel better if is began to stall or quit. But, turning the screw in pretty much has no effect. What else is happening here?
Thanks.
Click to expand...

If I remember correctly, the air fuel mixture screw is metering the fuel only as you adjust. So out is richer and in leaner. If there is no noticeable effect, then fuel must be leaking through somewhere. Have you tried driving it and see how it runs on the road? If you definitely have a mixture problem I personally would try rebuilding it again paying particular attention to all gasket placement.
 
I have driven it. It does cruise along at lower speeds and rpms. But, when I push the pedal, it sputters and hesitates.
 
Two steps back. So, I pulled the carb and repeated the rebuild process, including a thorough cleaning. Also, per an instructional video, I re-set the float height (41mm from the housing face to the bottom of the floats). Currently: it still runs rough, coughs and sputters. I can still turn the air / fuel screw all the way in and it doesn't change or die. Now, there's fuel dripping from the accelerator pump. ARGH. I think I'll give it a rest and do some more research. Thanks.
 
GregMP said:
Two steps back. So, I pulled the carb and repeated the rebuild process, including a thorough cleaning. Also, per an instructional video, I re-set the float height (41mm from the housing face to the bottom of the floats). Currently: it still runs rough, coughs and sputters. I can still turn the air / fuel screw all the way in and it doesn't change or die. Now, there's fuel dripping from the accelerator pump. ARGH. I think I'll give it a rest and do some more research. Thanks.
Click to expand...

If idle screw does nothing idle may be too high opening mains, or fuel level too high letting gas by, needle was tightened too hard damaging seat or needle, incorrect sequence of needle assembly. also carb to manifold gasket leak. Aftermarket generic parts?
 
Apparently, the stock mechanical fuel pump puts out as much as 15 PSI. However, the Weber carb only requires about 3 to 4 PSI. So, it's no wonder that my carb is basically flooding, the floats can't control the fuel level, the air / fuel screw is in-effective, it runs rich and it's blackened my spark plugs. Remedy? I'm going to install a fuel pressure regulator and slow the flow down to about 3 PSI. Thoughts? Thanks.
 
GregMP said:
Apparently, the stock mechanical fuel pump puts out as much as 15 PSI. However, the Weber carb only requires about 3 to 4 PSI. So, it's no wonder that my carb is basically flooding, the floats can't control the fuel level, the air / fuel screw is in-effective, it runs rich and it's blackened my spark plugs. Remedy? I'm going to install a fuel pressure regulator and slow the flow down to about 3 PSI. Thoughts? Thanks.
Click to expand...

The factory type fuel filter is split on the output with one side returning to tank. I am just using a standard one inlet one outlet filter and not having a problem with my Weber. Your pump is probably putting out more than mine. You might try one of the stock type filters if you don’t already have one.
 
My plans going forward: The previous owner swapped the Carter Carb for a Weber carb. That swap eliminated the electronic carb control system. Through research it appears that it's now time to perform what's called the "Nutter" bypass process, or at least verify weather the PO did it and if done correctly. After that, I need to track down any vacuum leaks and there are some vac lines that can be eliminated or sealed off. I will also be installing a fuel pressure regulator unit to bring the fuel pump pressure down to about 3 psi. Sheesh! Restore a Jeep they said. It'll be fun they said. Argh.
 
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So, I did the "Nutter" by-pass and crossed my fingers. When it does start, it runs (idles) like a two legged dog. I swear it's the carb, which I've bee through a few times by now. I was hopeful, but I'm not there yet. Next possibility(?): Pro carb rebuild? argh. Thanks,
 
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