Y'all are not reading me. I can start it. Starting is not the problem

It runs rough after starting as though it never warms up.

 

you could be having a icing problem ?

 

It could be a case of the carburetor icing up especially if there's a lot of moisture in the air when the outside temperature is just around the freezing mark. If you have a 2-barrel carb,Ford used to install a heated spacer under their carbs to help with this problem. The spacer simply is connected to the heater hoses so that the coolant flows through it and warms up the base of the carb. You should be able to find one of these spacers in the boneyard. They were quite common. Could be worth a try.

 

I was thinking icing. I thought that's what the riser with actuated flap was for on the air cleaner. My carb does have the heated spacer I think. I'll double check.

 

Are you missing the choke heater tube? Small metal tube runs from exhaust manifold to carburetor. Mine was missing - O'Reilly Auto Parts ordered one for me.
Fixed mine.

 

qman,

I have a similar truck, the one in the avatar. That flap won't help your poor running when warm. I leave mine open all year, and it's 12 F today. You need your choke set up properly, and may also need your choke heater tube, as phil105 states above. Contact FMC400 on this site. He has helped me out before and has the best instructions for setting up your choke that I've ever seen.

Heres one:


https://www.ford-trucks.com/forums/8...-answered.html

I'll try and find the other...


Here it is: https://www.ford-trucks.com/forums/7...-not-idle.html


Scroll down to: 08-06-2008, 11:58 AM, and read FMC400's explanation.

You may want to copy this for future reference(I did!)


Cheers,

John

 

Thanks dudes.

 

My 71 390 had similar problems, started hard (but started), would not run worth crap until the engine got up to temp, which took forever. I replaced the automatic choke with a manual choke, starts great and I can leave the choke on a little longer, runs and drives normal cold and warms up a little quicker. Saving gas, cause I'm not letting it idle for 10 minutes before driving. Still started a little hard, so replaced the battery with the highest cranking amp (770) battery NAPA had. Now if I can just get the driver side tail light to work 100% of the time, I'll be happy!

 

If tail light works but not all the time . . . turn signal switch.

 

Sounds like the choke pull off may not be working. When the engine is cold the choke should be completely closed. To start the engine you will need to pump the throttle a couple of times. Then start the engine. As soon as the engine starts the choke pull off opens the choke just enough so the engine doesn't flood/run way too rich. As the engine warms up the choke should open until it is completely open. When the choke is closed it also should increase the idle of the engine. There is an adjustment for this near the base idle screw. It has a cam that a high idle adjustment screw that makes contact with it. A way you can tell if it is operating is to pull the choke rod closed and blip the throttle to see if you can get it to stay on high idle. Next step is to pull on the choke rod against the vacum choke pull off. If the engine runs rich while you are pulling it closed you will need to adjust the pull off so it isn't too rich. The way this works is when the engine is first started the choke pull off will open the choke enough to prevent flooding of the engine. Some have a screw to adjust but most you bend the linkage to adjust.

If the choke is adjusted right then the next step is to make sure the heat riser is working. Cold engine the flapper in the air cleaner should be closed or diverting air from the manifold. The heater tube needs to be secured to the heated exhaust air manifold. This diverts warm air from around the exhaust manifold into the air cleaner. It is nothing more than a vacum thermo swith and a vacum motor that closes the cold air intake in the air cleaner. Also check if your engine has the warming plate at the bottom of the carb. If it does I would check for coolant flow through the warming plate.

Sure, they will run with out the warming tube. Most on the road are probally not working anyhow. But it does help.

As for the higher octane I would not run it in the winter. Octane is in the fuel to prevent pre-ignition from high compression. Probally won't notice this effect on cold starting unless extremely cold.

I would check your spark plugs too. If in fact it has been running rich they could be carboned up and not make it any easier to start or run smoothly. While your at it check compression.

You could go to a manual choke and yes they work. I personally would get the auto choke working. Reason being if you forget to open the choke fuel milage suffers. But it also suffers when the auto choke isn't working right too!

Hope this helps!!!