Old Fairmont does not like the cold.

chrisnorton65 · 12-12-2011, 09:47 AM

I have a '78 Fairmont. It will start in the cold mornings but if it dies during warming up or even after warmed up it will not start again. Do I need to keep it warm over night somehow cuz it will start all day long once it is warm outside? I have even drove it 2 miles after it warmed up for 10 minutes and it died and would not re-start. It would just crank until the battery dies. It has antifreeze in it, new plugs and wires. Could it be the battery? I need ideas. Thanks.

grog11 · 12-12-2011, 04:21 PM

is there a crank sensor on that engine? That can cause that type of issue.

Kruser · 12-12-2011, 07:45 PM

Originally Posted by chrisnorton65

I have a '78 Fairmont. It will start in the cold mornings but if it dies during warming up or even after warmed up it will not start again. Do I need to keep it warm over night somehow cuz it will start all day long once it is warm outside? I have even drove it 2 miles after it warmed up for 10 minutes and it died and would not re-start. It would just crank until the battery dies. It has antifreeze in it, new plugs and wires. Could it be the battery? I need ideas. Thanks.

Ah....the era of the carburetor and cold mornings. 4, 6 or 8 cylinders? Doesn't really matter, but the 6 cylinder engines had a carb that was super finicky in cold weather, ALMOST to the point of the only real fix was to install a manual choke. But that's another matter....
Does it crank over okay? If so, rule out the battery.
Okay, for those of you who are too young to have ever dealt with a carburetor, I'll give you a short lesson.
First off, there is no computer on this car, per say, unless you claim that electronic ignition is a computer. It has electronic ignition, a big improvement over points, but that is it. There are also no O2 sensors and no crank sensor on it either.
To the point of boredom, we'll start with the theory on these engines. Assuming that all parts are working properly, when a carbureted engine sits out at night in the cold air, the choke is wide open. Unlike a fuel injected engine, the first thing you must do before attempting to start it, is to step on the accelerator pedal. This does two things. It closes the choke completely, and it gives the engine a shot of fuel via the accelerator pump. With the choke closed, the fast idle mechanical linkage, if adjusted properly, will also make the engine idle fast when it starts. We are now ready to start the engine. When the engine starts, the choke-pull off opens the choke up slightly. If the choke pull-off section is not working, the exhaust will probably have black smoke coming out of it. The engine should also be doing a fast idle. Does it? As the engine is now running at fast idle, the choke will slowly start to open up. The speed of this depends on the specific model of car and how cold it is. The choke plate will be the top plate on the carburetor. (The bottom plate is your throttle plates) With the air cleaner off and all vacuum hoses plugged, you should be able to watch the choke plate slowly open up. Is it opening? As the choke plate opens up, the fast idle circuit should disengage. Some cars do it automatically. On some cars you have to tap on the accelerator to have the idle drop down to normal.
I have not seen your car in person, so a couple of questions: Do you have black smoke coming out of your exhaust pipe? (Black smoke is excessive fuel being burned, blue smoke is excessive oil being burned) If you have black smoke coming out of your exhaust, some part of the choke system is probably not opening up. Just by your explanation, I'm going to guess you have a choke problem. Unless of course you have an ignition or other problem. If all this is too complicated, get a seasoned mechanic to look at your car. The young guns at a dealership will be clueless.
I wish I could be there in person to troubleshoot your car. Sorry for the long and rambling post.

toby tough · 12-12-2011, 08:08 PM

Ah yes, back in the day when you opened the hood and actually saw an engine in there instead of hoses and wires and gadgets everywhere. I think if his choke was stickin' wouldn't the engine drive pretty crappy,along with the black smoke?Maybe the next time it dies on him he could check to see if the carb is gettin' fuel still. Those fuel filters they used back then weren't very big,easy to get pluged up. Maybe also he could have some moisture under the dist. cap.check for cracks and a carbon trail in there.I had an 86 GMC pickup that had a bad module.It would quit on me when the module got hot.Idon't think the Fairmont has anything like that does it? Oh well,just a few ideas.

Kruser · 12-12-2011, 09:40 PM

Originally Posted by toby tough

I had an 86 GMC pickup that had a bad module.It would quit on me when the module got hot.Idon't think the Fairmont has anything like that does it? Oh well,just a few ideas.

The Fords of this era had the big aluminum ignition module that mounted with three screws to the fenderwell. When they first came out, they failed all the time. Sometimes when they were cold, sometimes when they were hot, I had one fail once that made the car ping horribly. Most of the failures were from cold solder joints that were not serviceable or repairable because they were encapsulated and there was no way to tell just by looking if it was bad. Later years they really improved them. It was always a "pleasure" calling the parts stores to order these because they had about a half a dozen different modules for the same year, make and model. I believe there was the white version, the blue version, the double blue version, the green version, etc. Pretty sure each color stood for a different version, such as California, high altitude, etc.
It could be the module, along with a dozen other things.

chrisnorton65 · 12-13-2011, 01:48 PM

Hey Kruser, that was some very helpful info. By the way, where do you live in KS? I live in El Dorado. No black smoke, it is normal color and the battery is cranking fine. The fuel filter was also replaced last week. However it does not fast idle when you first start it. My friend said the choke is not opening. He had to open it manually and spray it with starter fluid then it started right up. What about the distribtor cap like toby said?

Kruser · 12-13-2011, 04:57 PM

Originally Posted by chrisnorton65

Hey Kruser, that was some very helpful info. By the way, where do you live in KS? I live in El Dorado. No black smoke, it is normal color and the battery is cranking fine. The fuel filter was also replaced last week. However it does not fast idle when you first start it. My friend said the choke is not opening. He had to open it manually and spray it with starter fluid then it started right up. What about the distribtor cap like toby said?

If the distributor cap was wet and has no other problems, take some WD-40 and spray the inside of the cap. That's really all I use WD-40 for. The "WD" stands for water displacement as there are much better penetrating oils out there. WD-40 does not conduct electricity inside the distributor cap and dries it out in no time. In your case though, a wet cap is probably not your problem.
I think you and your friend have found what the problem is. I'll step out on a limb and say you have a 6 cylinder? If so, those are one of the poorest cold weather carbs ever made, IMO. Anyway, you've got to troubleshoot the thing and find out why the choke plate isn't opening. Remember that it should open up slightly when the engine starts and then slowly (within 5 minutes or so) open up all the way after it is running. There should be some fast idle adjustment screws on the side of the carb that set your fast idle speed. When the engine is warming up, it should be running at a fast idle and after it is warmed up, the idle should be normal. If it was mine, I'd put a carb kit in it. They are cheap, will pay for themselves in the fuel that you save and will stop your aggravation. With a car of that age, throw in a new float for insurance.
Oh, yea. I live north of you about 3 hours by car. On a day that we have a strong south wind, I could almost throw a frisbie into Nebraska.

Poppy · 12-14-2011, 04:37 AM

Hey, it's great having some old geezers here with brain cells that are still functioning well enough to remember how a carbed engine works, and to be able to explain it! Good job men!

chrisnorton65 · 12-14-2011, 01:40 PM

Thanks for all your help Kruser. We will be getting the carb kit soon.

Kruser · 12-14-2011, 02:01 PM

Originally Posted by chrisnorton65

Thanks for all your help Kruser. We will be getting the carb kit soon.

Well, hopefully I didn't steer you wrong. (Weak attempt at humor)
Anyway, you never did mention how many cylinders you have, which really doesn't matter except for your choke pull-offs. Some of the 302 engines have an integrated choke pull-off (which is included in the kit) and some of the 302 carbs have as a vacuum pull-off that is separate from the carb body, attaches with screws and has a small vacuum hose that activates it. This choke pull-off is considered separate from the carb and you'll have to pay extra for it. Anyway,it doesn't matter if you have the 4, 6, or 8 cylinder, make sure that you put on a new choke pull-off along with the kit and the float.
To order the carb kit, there should be some numbers either stamped into the carb body OR your carb will have a little triangular metal tag on it that can easily be lost or forgotten. If yours has (had) a metal tag, hopefully the last person who worked on the carb remembered to reinstall it.
In my case, I needed a new carb kit for my '71 Cougar a few months ago. The car is original, and has the original metal tag on it. O'Reilly auto parts argued with me that the numbers didn't mean a thing to their parts book or computer and wouldn't give me a kit. Autozone had no problem with the number and actually had the kit and float on hand. It's really too bad, but most of the old good mom-and-pop stores around here have suddenly copped an attitude or now charge extra to have it shipped to their store in 3-4 days.
Good luck.

Zephyrman · 12-14-2011, 09:50 PM

I was gonna throw in my .02, but Kruser has it covered. I used to hate dealin with the carb on my 79 Granada on a cold morning.

toby tough · 12-15-2011, 11:44 AM

Somebody else actually had a granade. Iused to have a maveric also.Acouple things I don't readily admit.Pretty good cars tho.

chrisnorton65 · 12-15-2011, 02:17 PM

Sorry about that man. Its the 6 cylinder.

MichaelJennnings · 02-09-2012, 07:09 AM

Originally Posted by chrisnorton65

I have a '78 Fairmont. It will start in the cold mornings but if it dies during warming up or even after warmed up it will not start again. Do I need to keep it warm over night somehow cuz it will start all day long once it is warm outside? I have even drove it 2 miles after it warmed up for 10 minutes and it died and would not re-start. It would just crank until the battery dies. It has antifreeze in it, new plugs and wires. Could it be the battery? I need ideas. Thanks.

The one thing that you will need for a carb overhaul besides the parts is a choke angle gauge. These were magnetic protractors that attached to the choke plate and were used to set the choke pull off angle. If not set correctly, the choke might open too far causing the engine to stall. Not far enough and it would flood the engine again causing a stall. I don't know how many of these I worked on over the years I was turning wrenches. Finding someone usually an old timer, with this tool is going to be hard in today's car market. When you rebuild the carb, don't neglect the float setting along with any other adjustments. Pay close attention to the VECI or spec sheet with the carb kit for idle, fast idle and pull off settings. You will also need to adjust the idle mixture when done. It isn't anything hard, but if you get it too rich, you will fail smog. Too lean and you will have a rough idling engine with stalling problems.

Kruser · 02-09-2012, 08:11 AM

Originally Posted by MichaelJennnings

It isn't anything hard, but if you get it too rich, you will fail smog.

FYI:
The OP with the '78 Fairmont lives in Kansas where there is no emission testing. I'm sure the California residents will freak when they read this, but the adjustments will probably be done for best drivability. In other words, with a tach, a vacuum gauge and the feel of seat-of-your-pants performance.

MichaelJennnings · 02-09-2012, 10:08 AM

Originally Posted by Kruser

FYI:
The OP with the '78 Fairmont lives in Kansas where there is no emission testing. I'm sure the California residents will freak when they read this, but the adjustments will probably be done for best drivability. In other words, with a tach, a vacuum gauge and the feel of seat-of-your-pants performance.

Don't I know it. I was a CA BAR Cert Smog mechanic for years. My dad taught me how to adjust the idle air/fuel mix with a screw driver and glass of water. Set the glass on the dash and adjust the mix until the water isn't moving. Best seat of the pants advice ever. It wasn't until years later that I learned why this worked. After all, I was in high school when he taught me this trick.
Since he lives in a state with no testing, then adjust for best feel when in gear. But the advice for the choke pull off adjustment is still valid and important since his original question was cold drivability issues.

Skyhawk · 02-09-2012, 01:15 PM

If your choke "pull off" is electric you can check the connection and test the mechanism with battery voltage. Given the age of the car I would replace the choke pull off. If the pull off is activated by hot air then look for a rusted tube. The choke spring gets hot air from the intake maniford or the exaust manifold and it is common for the metal tube to rust. I usually replace the tube with copper tubing and eliminate the rust problem. The upshift for the automatic trans of that vintage was also controlled by manifold vacuum that was transmitted via a metal tube that would rust and cause the trans NOT to upshift. Same solution, i.e. copper tubing. Also, in that vintage car, IIRC, there is an exaust dampner that restricts the exaust flow until the engine warms up. This devise is also controlled by a bimetalic spring that can rust out and not open the dampner and restrict the exaust flow. I cannot remember when this devise was eliminated so you may or may not have one. Anyone?

Kruser · 02-09-2012, 03:55 PM

Originally Posted by Skyhawk

If your choke "pull off" is electric you can check the connection and test the mechanism with battery voltage. Given the age of the car I would replace the choke pull off. If the pull off is activated by hot air then look for a rusted tube. The choke spring gets hot air from the intake manifold or the exhaust manifold and it is common for the metal tube to rust. I usually replace the tube with copper tubing and eliminate the rust problem. The upshift for the automatic trans of that vintage was also controlled by manifold vacuum that was transmitted via a metal tube that would rust and cause the trans NOT to upshift. Same solution, i.e. copper tubing. Also, in that vintage car, IIRC, there is an exaust dampner that restricts the exaust flow until the engine warms up. This devise is also controlled by a bimetalic spring that can rust out and not open the dampner and restrict the exaust flow. I cannot remember when this devise was eliminated so you may or may not have one. Anyone?

Pretty sure the OP got his car fixed a couple of months ago, but it doesn't hurt to have another post on the subject....
I'm sure there might be an example somewhere, but I don't know of any choke pull offs that are electric, or at least on a '78 Fairmont. I don't know of any choke pull offs that are activated by hot air. Remember that the pull off only does its job the first couple of minutes that the car starts, and in this case it is activated by cold vacuum. Now if we are talking about the carburetor choke thermostat, that could very well be electric. This model car had an electric choke thermostat with no troublesome heat tube going to it. It probably wouldn't be a bad idea to replace it, but if it works fine.......
The OP also stated that this was a 6 cylinder. I don't believe this car has an exhaust damper. They were most effective on V8 cars to send the hot exhaust under the floor of the intake manifold to quickly heat up the fuel/air ratio. I cannot remember if these were put on six cylinder cars. Anyone?

MichaelJennnings · 02-09-2012, 04:51 PM

Originally Posted by Kruser

Pretty sure the OP got his car fixed a couple of months ago, but it doesn't hurt to have another post on the subject....
I'm sure there might be an example somewhere, but I don't know of any choke pull offs that are electric, or at least on a '78 Fairmont. I don't know of any choke pull offs that are activated by hot air. Remember that the pull off only does its job the first couple of minutes that the car starts, and in this case it is activated by cold vacuum. Now if we are talking about the carburetor choke thermostat, that could very well be electric. This model car had an electric choke thermostat with no troublesome heat tube going to it. It probably wouldn't be a bad idea to replace it, but if it works fine.......
The OP also stated that this was a 6 cylinder. I don't believe this car has an exhaust damper. They were most effective on V8 cars to send the hot exhaust under the floor of the intake manifold to quickly heat up the fuel/air ratio. I cannot remember if these were put on six cylinder cars. Anyone?

Kruser,
You are very correct. Almost all CPA's were vacuum operated. The choke spring however could be either electric or manifold heated. Most cars of this vintage were electric although some still used that dumb tube or manifold crossover to heat the spring so the choke would stay open. I worked emissions & tuneups from 1980 until the mid 90's I never saw a CPA that was electric. I performed hundreds of carb overhauls on everything from Rochester (GM) 2 barrels to Fords Variable Venturi (Terrible venturi) to Chrysler's Thermoquad to Zenith Side Drafts so I think, at least in this case, I can be qualified as an expert in the subject. I'm not blowing my own horn and I don't usually state qualifications since I am no longer in the industry professionally. The CPA and choke spring were 2 different components of the choke system on carbs. As for installing a manual choke, this, at least in California, could violate the smog laws and cause the car to fail smog. Understand that most states laws were patterned after the California laws of the early 80's so most are very similar to what we dealt with and have to still deal with here in California.