Carb Sputtering issue

C

cropro27

New member
I am sorry for reposting something that might have been talked about before. But there is just so much stuff to go through. Anyway here is my setup. I have a 1976 IH terra with a 304 v8 2bbl carb. Here's my problem. My dads friend convinced my Dad to replace my original carb with a remanufactured one from kragen's. Everything was working fine, but after a few weeks the truck started to sputter. It worked fine cold but when it wormed up thats when it would start to sputter. It would only sputter when I gave it gas from a dead stop at a stop light until second gear. Then it ran smooth. I have taken the carb off, disassembled it, and cleaned it out thoroughly and still the problem occurs. If anyone has had this problem and solved it let me know what to do.
 
Yes. There is good gas flow out of the jets. I never had this problem until I got the rebuilt carb. I just don't understand that it only happens when the engine is warm and when I give it gas from a dead stop and only until second gear. Once second gear engages it runs smooth.
 
How does it idle? Try a little shot of carb cleaner down each bore and let us know if the engine speed picks up for a bit on one of the bores but not the other.
 
I think you're going to need to borrow or buy a vacuum gauge to diagnose this. Also, just to confirm is your ignition timing set somewhere between 0-10 deg before tdc? And is the smog system installed and working on this engine?
 
I really don't think it's a timing problem. I had that done by someone who knows what they are doing. It only sputters when I give it gas from a dead stop.
 
Fair enough on the timing. Doesn't sound like you have a timing light. Just trying to rule out the obvious. Would you check the distributor and see if it's tight? Also that the carb is snugly bolted to the manifold. And that the vacuum hoses are connected.
 
Everything is tight and connected. Plugs look good. Do you think that a carb spacer might be the answer? I'm not mechanic so I'm not going to tear into the engine and I don't think there is a mechanic in my area that knows scouts.
 
Adding a carb spacer May add a few hp, but don't start changing things until this problem is resolved. What was the problem with the old carb? And can you get a vacuum gauge?
 
There was nothing wrong with it. Other then it was 30 + years old. I never wanted to get rid of it. I would have to buy the vacuum gague. What are you thinking with the vacuum?
 
I will chime in here but will admit up front that I am no kind of expert.

Stumbling from a stop is the result of one of two things--either a lack of gas or too much air. Lack of the former makes a surplus of the latter. If you have a surplus of the latter you will have a lack of the former.

To attack the problem you have to discover what it is you have too much of or what it is you lack.

In most cases, too much air is due to a vacuum leak somewhere in the system. Vacuum hoses, vacuum accessories, carb mount, cracks in the throttle plate, and a loose throttle shaft are all areas in which excess air can be introduced to the system.

In most cases, too little fuel is due to a problem in the carb itself. Not enough stroke on the throttle pump, dirty passages, faulty power valve, low float level, etc. It could also be a lack of volume from the fuel pump, an issue I recently had (the symptoms were lack of power and sputtering under load).

The only way in which to determine what is causing the problems is you need to go about the diagnosis in a step-by-step order so that you can eliminate issues before you start throwing $$$ at new parts that most likely don't need replacing.

Eliminating issues that don't cost any $$$ is better than spending a lot of $$$ only to discover later that the cause of the problem was a no-dollar fix.

Good luck.
 
A couple more thoughts since this problem seems to be temperature related. A vacuum leak, while certainly still a possibility, is generally problematic whether the engine is hot or cold. One additional thing to check is choke function. A partially applied choke will create performance issues on a warm engine. The choke plate must be able to close and open fully without binding up. If automatic, it should be fully open after 5 mins of run time. If manual, verify that a fully pushed in knob is opening the plate all the way. If this is a 2300 modular model, there should be an approximately 1/4 thick Holley or felpro base gasket in place which includes a fuel bowl heat shield. Fuel percolation from engine heat is most problematic at idle and part throttle situations.
 
So everybody seems to tell me that it's either a vacuum leak, lack of fuel, and/or a choke issue. Scoutboy74 I have a automatic choke. Also scoutboy74 here is the carb info you wanted.
R 7214 a
465529 c91
0968
I don't know if that in what you were looking for but it's the only numbers on the carb. Marko and fdchappie I have replaced all the vacuum lines with new ones. Just wondering, but if I were to hook up the vacuum lines in the wrong place could that cause this sputtering issue?
 
Those numbers identify it as a 2210, which would be a direct replacement of the stock unit. I'm not a huge fan of this model. They can be dealt with, but they're often more trouble than they're worth. The quality of reman parts, especially carbs is not what it once was. Media blasting, shoddy service parts and incorrect gaskets are the norm. I'm not saying throw the thing in the trash. It might be fine and hopefully it is. These are just things for you to be aware of. It's too bad the friend doing all the urging didn't suggest a brand new Holley list 0-7448 2300 as a replacement. That would be a legitimate upgrade.

So it has auto choke, but have you actually watched the choke plate movement from a cold start with the filter canister out of the way? If not, you should. Your problem could be as simple as a choke that's out of adjustment.

Yes, incorrect routing of the vacuum lines could cause performance issues.
 
Scoutboy74 let me ask you this. Could you rebuild the 2210 by using a 2300 rebuild kit? If I can't then what can I do to deal with this lack luster model? Also where would be a good place to find a vacuum hose diagram for a 76 304 terra?

Well its kinda hard to drive with the hood up and really see whats going on. So no I haven't delt with my issue that way, but I have had the engine running with the hood up and the canister out of the way. It works fine but im not mechanic. So I'm not sure if what I perceive as normal is normal.
 
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