1054768
Sorry this post is so long-winded:
I have the non-stepper motorized Carter BBD 2bbl carb in my YJ. I believe that stepper motor is there to control the metering pins that adjust the fuel mixture according to the oygen sensor, which is controlled by the computer, but you've done the Nutter bypass?
I don't know much about that.
I have metering rods in my carb which are controlled by a vacuum piston contolled by a rod metering cam slid and screwed down into the accelerator pump lever which runs through the bowl cleaner of the carb.
For a very short while, I'd have to floor the pedal while turning the key to get my YJ going. I can't remember what I did to overcome that. I believe it only happened to me when the engine was warm. I knew my choke and choke plate weren't working the way they should. I may've adjusted the carb thermostat choke cover to 90 degress rich from the index mark with a cold engine until I got some spring tension to close the choke plate, but I think that was for another reason. I did all of this after adjusting the idle mixture screws when the engine was at max operating temp.
One question: When the engine is warm, do you start the engine by pressing the gas pedal halfway down, or do you start a warm engine without any sort of pressure on the gas pedal at all? With a warm engine, If I remember correctly, I'd hold the pedal halfway down (according to the owner's manual that's what you're supposed to do), but that would give me that problem of having to floor the gas pedal (again, if I remember correctly). This is for sure with me: with a warm engine, I just start the engine without any pressure on the pedal and that works fine for me.
Alot more questions: Are you revving the gas while holding the key turned to crank the starter motor until the engine finally fires up? (If you do, that might damage your starter and/or your ring gear on the flywheeel). Or, are you turning the key again and again and again until it finally runs? If so, do you pump once before every turn of the key? If that's the case, you might flood the engine with gas and that's no good.
Also, do you let the engine completley warm up before driving to see if the engine hesitates. When my engine is cold it will idle nicely and hesitate while driving, but only if the engine is cold and the engine hasn't reached it's max operating temps. I ususally let my engine idle until it finally does reach max. It's a smooth ride from there.
As a process of elimination I'd suggest setting the idle mixture srews back to where you can start the engine normally again and let the engine warm up completely, and then see if the hesitation goes away. What I think is really happening is that when you hit the gas, the fuel is sprinkling from the carb into the intake manifold rather than spray-jetting. Vacuum leak maybe? As thinks heat up, the carburetor gaskets expand more than the metal in the carb, therefore sealing any leaks.
The only other thing I can think of is the float level in the carb needs adjusting.
Try this link
Carb Trouble-Shooting
edited by: MadMiracle, Feb 12, 2003 - 08:25 AM[addsig]