I have a 1983 Ford Bronco with a 4.9l 300 i6, I just bought the truck a couple weeks ago from the junkyard, so it didn't have a carb or distributor, and the previous owner already eliminated most of the emissions including the egr valve. It supposedly ran when parked, (the guy at the junk yard put an engine in it 3 years ago, for the previous owner who never paid him so he just kept the Bronco, in hopes that some knuckle head like me would buy it.) So far I've added an hei distributor, a new carb, new plugs and wires, and an air filter. So here's the problem; when I start the engine it runs rough and misses, it also has no power, these symptoms occur throughout any rpm. last night I got it running fairly decent, so I drove it around the property, not for much more than a minute, pulled back into the driveway, stepped on the clutch and it died, so I coasted to a stop and it wouldn't start back up. This morning I tried to start it and it wouldn't even try to start. So I guess my question is, why does my Ford run like a Chevy? Thanks in advance for any help. (I also posted this on the bullnose section of the forum.)

 

Several things.

Not timed properly.
Carburetor could need adjustment.
Carburetor needs to be cleaned.
Fuel filter needs to be replaced.
Needs new rotor and cap and spark plug wires and spark plugs.

And if it has been sitting without a carb or distributor..the inside could be dirty. Did you clean it?

 

I cranked the engine to TDC, made a mark on the pulley and set it to 12 degrees before TDC. It's a brand new carb and fuel filter, and I'm not sure how to adjust these single barrel carbs. One thing I forgot to mention is that I don't know where any of the vacuum lines hook up, including the one for the distributor.

 

Need to get a haynes manual and find someone to adjust the carb

 

You might also try the inline six forum since it's mostly 300 oriented.

Ford Inline Six, 200, 250, 4.9L / 300 - Ford Truck Enthusiasts Forums

What transmission does it have in it? Mechanical or auto?

Why did you have to make a mark on the pulley? Was it not facing the right direction? If not, your balancer could have possibly slipped, which means that it could come apart at any time (which isn't good).

As far as running poorly, and assuming that things are in good mechanical order, I'd say that you have vacuum leaks.

A quick check is to turn the idle mixture screw all the way in (if you have the stock carburetor, it's the screw that's facing toward the passenger/front). If turning it all the way in doesn't kill the engine, you have a vacuum leak. (Also, never tighten down the screw or you'll damage it).

For starters, get a vacuum gauge and connect it to direct manifold vacuum (preferably the vacuum tee that's coming off the manifold). What is your vacuum reading at idle? Is the needle stable or is it all over the place? A healthy engine should be at around 18 - 20hg at idle.

Next, hold the vacuum gauge in one hand and take a can of compressed carburetor cleaner in the other. Spray liberally all around your gaskets, paying special attention to each of the six runners on the intake and where the carburetor is bolted to the intake. If your engine hesitates, the vacuum increases or decreases, etc. You've found a vacuum leak, and you need to address it before doing anything else.

If that's okay, disconnect ALL of your vacuum lines and cap them off. Your engine will run just fine without any of them hooked up. If it still runs rough, then it isn't a vacuum line issue and it's something else.

If your engine runs much healthier, then your lines are all screwed up.

You really only need 3 vacuum lines hooked up. A big one from direct manifold vacuum to the brake booster. A big line from direct manifold vacuum to the PCV valve. And then a line from a ported vacuum port on the carburetor to the vacuum advance port on the distributor. The ported vacuum port on the carburetor will be one that has 0 vacuum at idle, and then suddenly has full engine vacuum at higher RPMs.

If all of that is good, then (temporarily) disconnect and cap off the vacuum advance on the distributor. When it's idling, loosen the distributor and rotate it until the engine vacuum increases as high as it will go (it'll stop increasing at some point). Then rotate it the other way until it drops to around 1 - 1 1/2 hg below the highest reading. Check your timing. What is it? It should be close to the 12* initial. If it's wildly off, then your timing mark is wrong or you still have a vacuum leak. Reconnect the vacuum advance on the distributor.

Lastly, set the idle mixture screw on the carburetor. Rotate the idle mixture screw until you get the highest vacuum reading you can get. Then, slowly turn it the other way until the needle barely starts to drop. Stop and rotate it back out just until it reaches the highest vacuum again, and then leave it. That'll set your idle mixture.

Try all of that and report back on your findings.

 

I have the np435 4speed, I marked the pulley because the notch was hard to see, if I can get her to run I'll check the vacuum, thanks for the help.