I am having carb issues. Edelbrock 4 bbl. 302 Electronic ignition Flamethrower. At first it stalled and then I couldn't get it started. After getting it home. I rebuilt the carb and replaced the fuel filter. Put in some fuel stabilizer stuff in the tank in case there was any moisture in the tank form the winter.

Put the rebuilt and cleaned carb on and it started up. Now I can get it started but can't keep it going at idle. There are so many variables on a carb I am having trouble figuring it out. I have been playing with hte idle mixture screws on the front of the carb but no matter where they are it runs rough and dies. I have a couple of questions.

Fuel pump: I know that it is getting fuel. It seems to be uneven pressure. Squirt and then the pressure dies. it is very quick. THis is the old fuel pump on the 302. Is this normal?

Are the mixture screws on the front to be adjust one at a time?

IS there a carb expert in the area near Boulder that could help a bronco Brother out? I want/need to get this thing back on the road. Starting to take a bit of heat for it not running these days.

Flick

Flick (A Christmas Story anyone?),
Turn both mixture screws (gently) all the way in (clockwise) and then back them off a turn and a half. That should be a good start point. If you try to start the truck and still cannot get it to idle, adjust the idle set screw (located on the driver side of the carb, closest to the front of the truck, and attached to the accelerator linkage). You can set it a little high to get you running while you adjust the mixture.

If you still have trouble getting it to idle, try and check the timing.

While your doing the adjustments Frank posted above, make sure you have a timing light, tachometer (A light with tach is perfect), and a vacuum gauge while making your adjustments. This way youll have no other variables to deal with later. I like to have a fuel guage attached as well.

hmmm... I have none of those tools. This could be interesting. Are they expensive to pick up? I think my dad has a timing light back in New York. When I head home for the 4th I might see if he'll part with it. I doubt he is working on cars anymore these days.

hmmm... I have none of those tools. This could be interesting. Are they expensive to pick up? I think my dad has a timing light back in New York. When I head home for the 4th I might see if he'll part with it. I doubt he is working on cars anymore these days.

Well a cheap timing light is available at the part store. but you wont have a tach with it unless you buy a good one. I have no idea what I paid for my vacuum gauge. My fuel pressure gauge is inline on the vehicle or I have to put one on when I do his if it has an issue. when you rebuilt the carb I am going to assume you did replace your needle and seats, and the metering rods and jets are clean and the springs are good and your floats were properly set? Accelerator pump is working and no vacuum leak around the base of the carb? Go through everything you did again and make sure all adjustments were done properly.

I vote vacuum leak somewhere. It could be timing, but there's a pretty large range where it should idle fine. If you think it's timing try turning the distributor some in either direction and see if that helps. However with different timing, the idle speed will vary, but if it's close enough it will idle smoothly. The fuel on a mechanical fuel pump should squirt, as it's a pump ran by an eccentric. Does pumping it quickly or adding fuel/carb cleaner/something flammable help it idle? If yes, then it probably is a vacuum leak.

You normally have a higher idle with a vacuum leak. Unless it's huge then it wouldn't stay running once let off throttle. You used new base gasket?