Starts And Dies

My cj5 has the 4 cyl f head, it'll start and run from anywhere from 1 second to 5 seconds, but it quits every time. I took out the fuel line going into the carb and turned it over and fuel came out of the line when I first turned it over so I guess the carb is getting gas... any ideas? Thanks!

 

Does it die when you release the key from the "crank" position? (...assuming it is not a foot-starter.) Try a hot jumper wire to the coil input. See if it keeps running then... possibly a problem with the key switch or the ballast resistor?

And/or/also, the carb may be getting gas, but is the float valve letting enough gas into the carb bowl? Sticky float?

 

No, it runs for a few seconds and then gives up. And what do you mean try a hot jumper wire to the coil input? I'll check the float and stuff again but i think it's okay... Thanks for the help!

 

Sometime an engine will run only while cranking the starter. If you provide twelve volts positive directly to the coil terminal that the ignition switch feeds to, it will bypass the switch and the ballast resistor circuit and allow the engine to run - if that is the trouble.

 

Turning it in small increments, turn the steel idle stop screw in until it does run. It shouldn't take much. Then when it is running, look down the throat of the carb for excessive fuel flow. I should be dry after a few minutes. Are you using the choke?

 

Have you had it running after you changed spark plug wires? If so what was the last thing you changed or repaired?

 

Okay I'll try that!

 

Yes, it ran after that. I set the valve lash, took off and cleaned carb, and put in a fuel filter, I don't think I did much else.

 

Either the fuel filter is restricting fuel delivery or something is off in the carb after it's cleaning. I'd bypass the filter first to eliminate that.

Mike

 

Air leak under the carb?

You didn't lose the check ball/weight from the carb accelerator-pump circuit when you cleaned it? Many people have.

 

I ran the line directly into a cup with gas, and it still didn’t run for long.

 

I can check! I’ll probably take the carburetor off again.

 

X2

 

Get a can of starting fluid or a squirt bottle with gas in it. Start it then try to keep it running with spraying fuel or starting fluid into the carb throat. If it stays running that way, it's confirmed you have a fuel issue (or possibly a gross air leak into the manifold) and not any sort of ignition/spark issues My guess is fuel flow into the carb or an issue with the needle/seat in the carb. The latter is my vote since I've seen an inordinate amount of stuck needles in various ATVs and power equipment due to white corrosion caused my modern fuel.

If you use starting fluid, be careful! That stuff is positively explosive. If you're using gas, make sure you have good aim and don't spill fuel.

John

 

Also because too much can damage your engine.

 

Cheapest helper you can have. You don't even have to by him beer

 

While sorting this out also check the basic grounding of the ignition circuit. I've had similar issue solved loosening and tightening grounds. Also insure the points lead (from coil) is not shorting or close to ground.

 

It’ll start again if I put some gas in the carb. But I don’t know why it’s not getting gas, because when I disconnect the line that goes into it from the pump and crank the engine, some gas shoots out...