Engine Stalls and Sounds as if it is Missing

[Baldhead]

Hello, I'm new to the group and hoping someone can help. I have a 66 Mustang with an Inline 200. I added the the following:

1. Dual Exhaust Manifold
2. Weber 2 Barrell Carb with Fuel Pressure Regulator.
3. Replaced the fan with an Electrical fan.

When idling, the car seems to have a very subtle miss, but initially it will drive beautifully for roughly 30 minutes. At stops it then starts puttering and hesitating and if I try to accelerate it just cuts off. It then restarts but runs horribly (eratic missing). I talked to clifford performance and was told to do the following:

1. Check float setting (17.5mm) which i did.
2. Set the fuel pressure regulator to 2.5. which i did.
3. Adjust the fuel/air mixture screws. (Turn all the way in, then back out one full turn) which i did.

The car ran great for about 20 minutes, but after a long stop, same thing happened.

Can anyone help give me some pointers because I'm at a loss of what to do now.

I was thinking that maybe the exhaust manifold was creating too much heat under the hood affecting my fuel line. I was also told that one of the jets may be blocked, so remove all of them and blow them out. How do you do that!!!!!!

Does any of this make any sense to anyone??

 

[Lazy JW]

Howdy and WELCOME! to the forums

Does it always run well until it is thoroughly warmed up?
Joe

 

[Baldhead]

I'd have to say yes, but I can always detect that slight miss when it's idling in the garage. As a matter of fact for two days straight it ran well, then this past Saturday I took it out for a wash and wax (just let it idle), then all bets were off. I barely made it home.

 

[CobraSix]

How many tanks of gas has this been a problem? Has it been sitting a long time?

Generally, if the car isn't running well when warm, it can be tracked to a carb/fuel problem. Are you sure the choke is opening completely after the car is warmed up? Heat soak could be a problem, but I don't suspect it is in this case.

I'm assuming since you set the fuel pressure, there is enough fuel making it to the carb, or is the regulator before the fuel filter? Not sure this would cause your symptoms though. However, I thought these cars should be closer to 5-7psi, but I could be wrong.

Did the problems start after you added the 2V Carb?

While it could be an outside possibility, have you checked your spark when the car is warm? Possible that you have a worn out wire and the erractic nature of the problem (fine for 2 days, then bad) could point to either worn out points, a bad wire, or fouling of the plugs.

Speaking of plugs. Pull them and take a picture and post here. That'll help a lot.

edit: BTW, welcome to fordsix!

 

[Lazy JW]

...... I was also told that one of the jets may be blocked, so remove all of them and blow them out......

It seems unlikely that "blocked" jet would run well when cold, then give erratic problems only after warmup; it certainly never hurts to have things clean but this one just doesn't make much sense at this moment.

Since it runs well upon cold startup, it appears to be getting adequate fuel, HOWEVER, I have personally seen vehicles have similar symptoms caused by a partially plugged fuel strainer sock inside the fuel tank. If you are really ambitious, pull the tank, get it clean, and replace the fuel strainer. Again, it never hurts to make absolutely certain that things are clean; as for myself, I wouldn't do it just yet.

What we really don't know yet is if it is getting enough fuel or too much. What I would do is to run it until it starts its little tantrum, then pull the air cleaner and manually activate the choke while it is idling; if it isn't getting adequate fuel then choking it should show an improvement, and if it is is already flooding then it should make things worse (it may die and be difficult to re-start, so do this when you aren't in a hurry to be someplace).

Try this and then we'll take the next step. Don't make more than one change at a time though.
Joe

 

[JackFish]

I was thinking that if it's running OK when cold and gets rough when hot that it could be an electrical problem, like maybe a coil on the way to failing.

 

[Lazy JW]

I was thinking that if it's running OK when cold and gets rough when hot that it could be an electrical problem, like maybe a coil on the way to failing.

It certainly could be. One step at a time

 

[ludwig]

What's that old maxim - as found on FSF-? "If it seems like a carburetor problem, it's probably an electrical problem. If it seems like an electrical problem, it's probably a carburetor problem,"

 

[vssman]

Do you have a fuel pressure gauge permanently mounted to the regulator? If so, what's it reading when it start to run poorly vs when it's OK? If not, I'd put one in to help in determining if it's fuel related. You could also put in a clear plastic in line fuel filter to look for bubbles to see if your pulling in air somewhere.

Good luck...

 

[ludwig]

You may have debris clogging the fuel inlet. It starts okay, pulls up a bunch of sediment and gradually closes the gas flow. After you stop, the debris falls away and it starts/runs okay for a while. If it happens when you are at road speed, then goes away after you stop and turn the engine off, it is probably debris in the tank.

 

[CobraSix]

What's that old maxim - as found on FSF-? "If it seems like a carburetor problem, it's probably an electrical problem. If it seems like an electrical problem, it's probably a carburetor problem,"

I thought the maxim was "If you've come here looking for help...you must be really desperate"

 

[Baldhead]

Thanks for all the advice. I'm gonna actually look into each and every recommendation starting with the least and most simple options first. I wasn't able to download pictures of my plugs but i did pull them and Plugs 1 2 and 3 look ok (No carbon buildup)(Very Clean). Plugs 4 5 and 6 had significant carbon buildup on the Centre and Ground Electrod. Plug 4 had some oil around the threads. Does this buildup mean I have a problem with the air/fuel mixture??

Last, I noticed that there is absolutely no fuel in my fuel filter. I just installed a clear one and now it's as dry as a bone!!!

Any advice is welcome!!

Rob

 

[ludwig]

As to that last, I'm thinking 'no fuel'.