[djhawkeye]

I'm new the forum and until I started a rebuild of my grandmother's '66 Mustang in October I had never even changed oil on a car. Here's my problem with some details as well as things we have tried so far.

The car sat for almost 30 years in a garage
The engine has had a partial rebuild
Fuel tank, lines, fuel pump, rotor, points, spark plugs, wires, etc have all been changed
The Autolite 1100 carburetor was rebuilt by a local shop

The harmonic balancer and timing chain were replaced and we have been able to get the car started and timed to 12 degrees as stated for an automatic. Problem is, when you slowly give it gas it stutters and dies. You can push the gas pedal down quickly and release and it won't die, however, if you push it down fast and try and hold the pedal down the engine shakes a bit and dies. I've had a couple people double check the timing, we have verified that there is not a vacuum leak on the distributor advance, verified that the advance is indeed advancing the timing, but still can't get this thing to do more than idle.

As I'm not familiar with cars some people have suggested that there may be some adjusting that needs to be done on the carburetor since the person that rebuilt it likely did not set the screws to the same position they were in before.

Anyone have any suggestions? We've been trying to figure this out for days with no solution in sight.

Thanks in advance.

 

[heavy metal]

Welcome to the site!! I moved your thread for a better response.

 

[Explorer]

First thing to check would be accelerator pump. Looking down throat of carb, pull down accelerator linkage and you should see a squirt of fuel immediately. If not then linkage may not be set right. The accelerator pump will be on the drivers side, anti-stall on the passenger side connected with a rod passing under the fuel bowl.

 

[Driveway]

The shop would have put the needle valve at a basic point, like 1 1/2 turns out. Just to get the engine started. You need to readjust it while it is running.

You did not say you changed the coil, dist cap, or the fuel filter.

I agree a bad accelerator pump could cause this, but it should have been changed at the rebuild. Is there any gas leaking from it?

Double check the plug wires. A simple mistake we have all made.

It would take a big vacuum leak to cause you problem.

 

[djhawkeye]

The accelerator pump is working properly.

I did not replace the coil, but I did replace the distributor cap and I just rechecked the wires and spark plugs and everything is fine.

I did notice that it looks like the anti-stall was not adjusted at all. We have it running a little bit better where it doesn't die when you hit the gas but it gets close. My friend and I are leaning towards it being the carburetor not adjusted right. I don't have any experience adjusting that and he has a little bit. If I can get it where it will drive, the shop that rebuilt the carb will get it all tuned for me. Do yall agree that this may be the problem?

 

[Driveway]

Well, you are making progress. Go ahead and try to adjust the needle valve. Slowly turn it in until it starts to stall, then back it out half a turn. But you shouldn't have to go more than another 1/4.

I would also put on a new coil.

 

[ranchero]

no need for a new coil. the car runs. sounds like fuel.
a vacuum gauge and timing light would help you to better tune engine at idle. be sure to block off vac advance hose at distributor when setting the timing. 12 degs may be a good start, but you might need to go a little further.
hook up vac gauge to carb and adjust the air fuel screws and watch your vacuum. the higher the better in your situation. probably hit around 15-16 hg.
if car has been sitting, gas in the tank may be turpentine. be sure to check fuel filters and if there is a fuel sock on fuel sender in the gas tank. you'd be surprised how much dirt gets in a fuel line.
you can also do a quick test by running fuel supply line from gas can to the fuel pump. if car runs smoothly, you are narrowing down the problem area.
a new fuel pump doesnt mean you have a "clean" fuel supply.
i had a new pump get clogged from a tank that had too much dirt and no sender sock on it.

 

[djhawkeye]

I appreciate everyone's help here, but it looks like we finally figured it out. Since I didn't know much about cars, my neighbor had adjusted the carb for it to run good at idle. After not finding a solution I researched the carb and how to get it to the 'factory' settings so it would be close. Once I did that the idle was very rough and it didn't take me long to figure out the the PCV valve was bad. Changed that and the idle smooth out and it doesn't die when I hit the gas. Still need to fine tune the carb since there's a little hesitation when you gas it and let off, but I can drive it to the shop that rebuilt the carb and get it fine tuned for free.

This was my first experience on a forum and I want to thank everyone that tried to help. Maybe this solution can help someone else in the future.

 

[djhawkeye]

Even though everything is not perfect, I was able to drive the car around the block; bout a half mile at slow speeds. I'm trying to get it tuned a little better tomorrow and get new tires. Today was the first time the car drove in almost 30 years. My 95 & 99 year old grandparents are going to be so excited when I'm able to take them for a drive in their old car. That's the only reason I did the restore.

 

[ranchero]

you're a lucky person to be able to keep her in the family and take your family for a spin. cool!

definitely get some new tires!

and you may want to change the thermostat. keep an eye on the cooling system. those guys like to stick with age.

 

[67cpe]

you're a lucky person to be able to keep her in the family and take your family for a spin. cool!

definitely get some new tires!

and you may want to change the thermostat. keep an eye on the cooling system. those guys like to stick with age.

if you have around 20 degrees of advance at around 1800 rpm then your main jets are either partially plugged or need to be increased in size. buy 1 size larger

most likely, no amount of tuning will cure your prob.