back together and running rough

Finally got all the pieces back together. Now, after getting the engine to fire, it's running pretty rough. Sometimes it will idle fine, others not, and don't even think about running it under a load. It acts like it's running rich. The jeep ran fine before disassembly, then sat for 4 months with no fuel in the carb/bowl/tank. Installed new tank, new sending unit (which is not currently working!!), and now it's running like a hit and miss engine. I'm thinking maybe something inside the carb. Anyone have any experience with this? I'm considering carb rebuild to start. I have some other form of ignition(ie..no points and condenser, but have rotor button), so I'm not sure if everything is fine there or not. Considering that it ran fine before disassembly I'm gonna assume that some trash/dust etc... is in the carb.

Any suggestions?

 

I'm definately not a seasoned mechanic but I had a similar problem once and a little chemtool carb cleaner fixed it. In my case, I think that float was sticking.

 

Is that a chemical that you dump in the carb? Or is that something that mixes with the gas? I'm a seasoned mechanic, but considering I'm 30, and I've been in the business for 10 years, I haven't the slightest f-ing clue when it comes to carburetors!!! I know it sounds crazy, but I've only worked on HEI, fuel injected vehicles. Carburetors are a strange animal to me......

 

I read somewhere on here about the filter on the sending unit being pushed on to far and not letting the fuel pass like it should. Do you have the prestolite ign? It has a silver box that is connected to the dist. If you do you should think about replacing that system. But I think the prestolite ign either works or doesn't. It will cut out at odd times. I use two fuel filters also.

 

It comes in a spray that you can shoot down the carb and it also comes in a can that you can add to the gas. If you suspect its a dirty carb i would start with the spray but the gas additive works well. I add a can to every third or forth tank.

 

I got the sock in the tank, which is not pushed on all the way, as well as an inline type strainer type filter right before the carb fuel inlet. Is that your idea of two filters? Or are you using like a inline fram filter?

 

I have a inline filter right before the fuel pump and also one after the pump in the stock location up by the carb. I have a clear one by the carb so you can see the gas flow. Did you check your plugs. Maybe a mouse got to some wire somewhere?

 

Need more details - year, model, engine. It's good to put that info in your sig.

 

thanks for the advice. Point taken...

Now. Today I had it idling, as best as it could, then I introduced some more air to the mixture, ie..i opened a vacuum leak. The engine smoothed out and appeared to be running better. This tells me I'm running rich. So I guess it could be time for a carb rebuild? Maybe something stuck in the needle and seat? I'm not sure of the type of ignition I have, I'll take a pic tonight. However, I did replace all plugs wiith autolite standards gapped at .035.

 

The most common reason for running rich with a 2100 is a punctured power valve. That style of power valve can be ruptured by backfire rather easily. The Holley carbs (which also use that style of power valve) have a check ball that protects the power valve, but the Motorcraft carbs do not.

Take the power valve cover off and see if there is gas in there.

 

Thanks Tim...I'll check that tomorrow. BTW here are some pics of the electronic ignition that has been installed by the PO.

 

Ford.

Factory Jeep equipment from '78 on. "Motorcraft Duraspark." Good product. Make sure the ground from the module to the fender is good, and keep the connectors clean.

 

With this type of ignition you may want to open your plugs from .035 to .045-.048. Good luck.

 

sounds good, I will regap the plugs. I was afraid that I may have them gapped to tight for a higher energy ignition. BTW, I bought a carb rebuild kit and I'm gonna tackle that on Sunday. I'm kinda excited as it's something relatively "new" to me. That's so strange to say as I've been an automotive professional for 10 years now.