Question

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mojave450rider

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So I have a 304 with a Holley 2bbl and lately I have noticed that there is a discharge of kind of burnt looking area something appearing in between the 2 carb body halves at the joint where they go together and dont know why this is happening? What is the cause and a cure for this or is it ok? Thanks
 

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Looks like just a bit of seepage on the bowl gasket. I wouldn't sweat it or at most just check the the bolts on the bowl are still snug. Don't over tighten these bolts!
 
Ok cool I wasn't sure but now I feel better bout it. Eventually I am going to have the carb rebuilt cuz it never really seems to be running good at idle and what I mean it smells real Rich and the exhaust stinks but while driving it clears out so....
 
What's the list number of the carb as seen on the front face of the airhorn? Have your tried tuning it at all?
 
Have you set the fuel level? Remove the slotted brass plug on the passenger side and see if fuel sloshes out. Also does it drip down the carb after the engine is turned off?
 
1st things 1st, then the simple.

Ignition affects carb settings, carb settings affect ignition.

For the weepage, I would replace the bowl/metering block gaskets with the newer blue alcohol fuel resistant ones. They come in packs, you won't need the whole overhaul kit. The bowls and metering blocks are modular and are easy to remove/replace provided you can get to the screws. Your carburetor looks to be in good shape and that maybe all you need for now.

For the Rich burning smell, it maybe the ignition is out of tune. Are the plugs clean? Is the advance functioning correctly? Proper dwell and timing? Once you get the ignition verified, try setting idle quality at the right rpm with a vacuum gauge after verifying fuel level like fd sez. On your model of the carburetor, the idle screws on the metering blocks screw out to lean the mix. If nothing gels, then it would be time for a carburetor overhaul.
 
Ok so what number do I use to identify my carb with? Is it the top number stamped which reads 4412-3 or the bottom number which reads 2763? It's a 2 bbl Holley with manual choke on a 304. Thanks
 
Long time no squawk. 4412 is the list number. I suspected from your post last year that you might have one of these. The 4412 is a 500 cfm version of the 2300 model. A fine carb for an engine that can make proper use of its calibration. It is not generally considered as a great fit for most IH engines. Even with perfect ignition tuning and a well done carb rebuild, you'll still be running Rich most of the time. Its just less noticeable while driving than it is while idling in place. This carb is meant for engines that breathe and rev fairly high, like well above 4k. Two things your engine don't do.
 
Ya it has been awhile since mess'n with the old rig, long story short I got hurt at work and blah blah, anyways so back to the carb...so what should I do run this one or swap it for something more properly suited to an IH engine? Thanks for your informative response it totally helps out!
 
Glad you've healed up. I know about those otji's. If this rig is a limited use trail pig, you could perhaps get by for awhile. Otherwise, your long term ownership options call for a replacement carb or fuel injection. There will be a cost associated with a, b or c, however you could offset it somewhat by selling the 4412. There is a market for them amongst circle track racers. Your Scout is no econo-box even under the best of circumstances, but I don't see you ever reaching mid-teen mpg with that carb. If that was the only issue, you might say "so what" and roll with it. Unfortunately, along with the even crappier than usual fuel economy, there's also the excess fumes/emissions and potential for fouled spark plugs. If money were no object, this would be an easy decision.
 
A little in some regards perhaps, but not enough across the board to make it worth the hassle. The accel pump diaphragm is a whopping 50cc's. The jets are big too. I forget what size they are. Those can be exchanged for smaller ones. You'd have to figure out what size to use through your own trial and error. There's not a whole lot you can do to help the Rich idle, aside from turning the mixture screws in as far as you can without completely starving the engine for fuel. Then there's the power valve. Its kind of like trying to make a .45 into a .22 without having compatible barrels and magazines to swap around. As far as a new out of box carb...the best option is the Holley list 0-7448, which looks nearly identical to the what you have now. Internally they are quite different though. You can keep your eyes peeled for a good, used oem style 2300. One that isn't worn out and has been correctly rebuilt will do a fine job. IH used dozens of list numbers of the older 2300's on their v8 engines from the late 50's up to about 1971-72. Be careful of remanufactured carbs. Getting one from a reputable source is okay, but there are a lot of fly by night rebuilders turning out mismatched botch jobs these days.
 
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