Ok I just got done replacing my intake manifold gaskets and I got everything back together last night. The first time I started it up it was sputtering and wouldn't hold idle at all and the carburator was spraying gas out of the top like it wanted to backfire. I messed with the carb adjustments to see if I could get it to idle better but to no avail. Finally today I thought, maybe my distributor got turned a little bit off when I was putting it back together, so I messed with that and got it idling like it should and it's running as good as it was before.
But the carb is still damn sputtering!! It's not spraying gas out the top but it still makes this "POP" noise when I hit the gas or when it's driving down the road. It's a consistant pop like it's doing it every time it gets to a certain cylinder or something. It's driving me crazy and i'm so close to getting this thing driving like it should be!! Could it be a vaccum leak at the carb? I've checked, double checked and rechecked all the connections to the carb and everything seems to be in order. Any ideas? Could the distributor still be out of time a little bit??

 

What kind of carb does it have? Did you change the carb base gasket?

Reason I ask is that if you have the 4bbl that Holley made for Ford, the PCV port is on the back of the carb. Base gaskets that come in rebuild kits for standard holleys allow that PCV passage to be uncovered and create a huge vac leak.

BTW, did you put the 390 in that truck. The truck looks nice.

 

Two questions, did you actually set the timing to spec, or wing it? Also, when you disturbed your distributor, did you double check your firing order?

 

the pop is probably out of timing. if the gas is coming out the top it could be a sunk float or dirt in the needle and seat. my trck does that going down my driveway as it is a 30 % grade. i run it in first at high idle to run the gas through. check the timing, and look at the tube at the top of the carb, see if the fuel comes from it.

 

It's just a standard 2 barrel carb The truck came with the 390 but thanks for the compliment! I marked the distributor before I took it out but I guess it's still off timing a little bit. I guess it's still a tooth off or something? I just winged it but I definately made sure to mark the plug wires before I took them off and i'm 100% sure they're the exact way they were before I did the work. I guess I'm just gonna have to keep working on the timing.

 

Ugh, ok anyone know an easy way to put this thing at top dead center?
I give up on trying to wing it.

 

If your harmonic balancer is good use it. You may be 180 off, doing it this way, unless you pull the #1 plug and catch it on the compression stroke.

 

with the number #1 spark plug removed ...Take off the right bank valve cover and crank the engine by hand until you see the intake valve on #1 close.. now continue until turning the crank in the direction of firing order until you see the very top of the piston in the spark plug hole.
That is really close to TDC on Compression stroke and the S/P is ready to fire.

 

Ok I got it back to tdc yesterday and reset the distributor. It's idling great but the damn carb is still making that poping noise. I noticed it's got a very very small cloud of white smoke coming out of the right side (barrel?) of the carb. It only happens on acceleration and it does it consistantly. I also noticed my rotor button is bent I bent it back to the way it should be the best I could but I'm gonna go pick up a new one of those today. Could that be the cause?
Man I'm SO CLOSE!!

It's wierd, when I'm working on friends cars I have no problem diagnosing things but when it's my own truck I find myself second guessing everything.

 

Check the distributor cap for carbon arcing.

Also,Some of these caps have what looks like aluminium contacts.They corrode very easily

Try and purchase a dist cap that has the brass contacts ... It may take a while to find one.

 

Part No. 32100 if it is a Duraspark.

http://www.performancedistributors.com/accessories.htm

 

Did you readjust the air/fuel mixture screws? if OK

You may need to adjust the accelerator pump, to make it squirt earlier, less lag.