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Old 12-16-2017, 12:19 PM   #21
47COE
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Default Re: No start at gas station

Are you getting spark at the plugs?
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Old 12-16-2017, 02:17 PM   #22
4dFord/SC
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Default Re: No start at gas station

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Originally Posted by 47COE View Post
Are you getting spark at the plugs?
FYI, here's a handy gadget for testing same: https://smile.amazon.com/RAM-PRO-Eng...k+tester&psc=1
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Old 12-16-2017, 05:58 PM   #23
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Default Re: No start at gas station

Smell Gas, No Spark. Engine Externally looks normal
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Old 12-17-2017, 02:14 PM   #24
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Default Re: No start at gas station

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Originally Posted by chuck stevens View Post
Push starting works because there is no voltage loss from the starter. Trust me a resistor bypass works.
I think Chuck is correct. Your only dealing with 6-volts and it does not take much resistance to drop the voltage to where the coil will not put out a strong spark.

This is going to be long-winded. Only because I want you to understand how these things work. If you do not know how they work it's pretty hard to fix them.

If I was at work and someone came to me with your same story. The more details I could get out of them the better. Unfortunately I worked nights and the drivers were already gone when I arrived . Everybody was gone, just me a opossum and 157 vehicles, doing 100% of all repairs and services. Usually I had a repair ticket that said, "truck won't start". I hated that, do you mean truck won't crank or it cranks but it won't start? Was it hotor was it cold when this happened, how far did your drive it? A lot of these vehicles were in remote locations so the description made a big difference as to what I grabbed to go rescue it.

You have provided a very good description of the problem and given me a lot of info to work with. The problem we have is the vehicle is no longer broken, "not broke can't fix". There is a lot of truth to that statement with intermittent problems but we can narrow it down to a specific system, (maybe). At work on an intermittent problem I had the luxury of swapping parts between vehicles. If I suspected a $1000.00 computer was the problem I would swap it with another vehicle. If the other vehicle died the next day I knew the computer was the problem. We don't have that this luxury at home. So most people start "guessing" and replace a bunch of perfectly good parts and the vehicle runs fine. But it was running fine before you replaced the parts so how do you know you fixed it? The problem with this is you will never trust driving your car again because you can't be sure you fixed the problem. How are you going to know if you fix a problem that might only happen once a year for five-minutes or even five-seconds unless you know for sure what that problem was.

With your description I don't think it's a fuel issue but there is always the chance I'm wrong. Your engine was not sputtering and was not down on power before you shut it off. So we can assume the carb bowl was full when you shut the engine off and its going to be full when you try to start it again, (if it just sat for a few minutes). You parked the car at the gas station. We now have what is referred to as a "hot soak" condition but not a very long one. Could the fuel have expanded from excessive heat under the hood to the point it overflowed from the carb and into the intake, flooding the engine. Its possible, but if it has never done this before on a warm day and your engine was not running hotter than normal it's unlikely. Another thing that could go wrong is a defective accelerator pump. If it doesn't give it that extra squirt of fuel to help start the engine it will make it hard to start depending on how long its sat. On a cold engine it makes it almost impossible to start. On a warm engine it will probably start without it. So that's probably not the problem but it won't hurt to peak down the carb and see if its squirting. Also run the car up to operating temperature and shut it off. Then look down the carb to see if any fuel is leaking into the intake.

. If it had overflowed or dripping from a cracked carb you would smell it and you would see the fuel dripping into the intake. The engine would not start because the mixture is too rich. You hold the pedal to the floor while cranking to allow air to flow in and lean out the mixture. Also with the throttle blade wide open and the slow cranking speed there will not be enough vacuum to draw more fuel out of the carburetor, this also helps clear out that excessive fuel. Even modern computerized cars can get flooded. The computer has the ability to shutoff the injectors if it sees you hold the gas pedal to the floor while cranking. That's what us old-timers naturally do if an engine does not start so they designed that into the system. Say you had parked your car and had leaking injectors that flooded out the cylinders (leaking injectors are rare) holding the pedal to the floor would shut the fuel off and clear out the cylinders. I don't think your carb flooded over. Once it did start it would have puked and coughed until it cleared out all the extra fuel and you did not mention anything like that.

Now we move on to vapor lock. In 40-years I only saw it happen a few times and only on one type of vehicle. It took awhile to figure this one out. I worked at below 1000' above sea level and we had 1984 4x4 carbureted Suburban's that would run fine driving around town. As soon as they went up the mountain on a warm day they would quit running at around 5000'. If they sat for twenty-minutes they would start right up. What fixed them were new mechanical fuel pumps. The pumps should have been producing 5-6 lbs. of pressure but they were only putting out 4 lbs. There is 14.7 lbs. of atmospheric pressure at sea level, When you raise the pressure you raise the boiling point, the point a liquid turns into a gas. A fuel pump cannot pump a vapor. At the higher elevation with less atmospheric pressure the fuel was able to boil at a lower temperature and turn into a vapor. Normally 5-6 lbs. of fuel pump pressure would increase the boiling point to where the heat of the engine, at 5000' would keep that fuel in a liquid form but it could not do it at 4 lbs. That is what vapor lock is. Then you need to figure out which side of the pump your problem is. On the suction side of the pump you have lowered the pressure on the fuel by creating a vacuum sucking it from the tank. Now the fuel can turn into a vapor easier between the tank and the pump because there is less pressure on it That's why it is so important to keep that fuel line a way from the heat of the exhaust. If you think about our 4 lb. pump it probably was creating less of a vacuum on the suction side. Less vacuum on that side would mean less chance of the fuel boiling. Less pressure on the engine side of the pump, especially where there is more heat would cause the fuel to boil easier. Have you ever seen anybody hook a fuel pressure gauge to a mechanical fuel pump. I have not, most "professional" mechanics will just try a new pump. Its really important to know that your pump is producing the correct pressure and volumn. A 1 lb. difference can cause problems.

You mentioned you turned on the electric fuel pump, now that changes everything. That would have pressurized the line and most likely turned any fuel vapor back into a liquid. With pressure in the entire fuel line there is virtually no chance of vapor lock occurring. Modern cars with electric fuel pumps in the tanks have eliminated vapor lock by pressurizing the entire system. Some systems recirculate the fuel to keep it cool.

When you install an electric fuel pump near the tank you have increased the pressure in the line between the tank and mechanical fuel pump (if its still there) so there is less chance of the fuel boiling in the line. There are two types of electric fuel pumps. One shuts off in a closed position so the mechanical pump will not be able to pull fuel through it. The second kind shuts off in the open position so a mechanical pump can still pull fuel through it. If your using the electric fuel pump to just prime the system you will need one that shuts off in the open position.

I don't think its fuel, its electrical, Here is the thing with ignition systems, the higher the rpm the more demand you put on the ignition system. If a coil is marginal at idle its going to be really bad at road speed, same with the points and low voltage in the circuit. Since it ran fine after it started Chuck is probably correct that when cranking the engine pulled the voltage down to a point the ignition system could not produce a large enough spark. Or its possible during the "hot soak", or something is going wrong in the coil when it gets too hot.

If your battery is good you need to perform a voltage drop test to see if your loosing voltage somewhere in your ignition circuit. It might be only loosing enough voltage to effect it when your cranking. You need to find all the unwanted resistance that is dropping that voltage And check the voltage available to the coil while cranking. You need to take the reading with the wire disconnected to see the available voltage. If you check it with the ignition on, wire connected and the points happen to be closed you will be performing a voltage drop test and not checking for available voltage. Everybody needs a digital voltmeter if they are going to full around with old cars. Ask Santa for one!
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Old 12-18-2017, 10:47 AM   #25
fourfords
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Default Re: No start at gas station

Oh Man! That's the longest post I ever saw! Thanks for giving a hoot! There is strong spark to the coil. From there on, I don't know. I decided to remove the distributor and I took it over yesterday to a local expert who has the correct equipment. We'll see what happens. I read the post several times and learned. Thank you!
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Old 12-27-2017, 10:12 PM   #26
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Default Re: No start at gas station

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Problem solved. Points were burned, also found the little carbon insert had separated from the spring of the coil on the bottom of the distributor. Made corrections. Just took the car for a spin. Badda Boom, Badda Bing! Some subtleties in this like making sure the coil is installed directly down so the carbon tipped contact and the copper coiled spring is centered in the cup on distributor. Thanks to all! I learned some cool stuff.
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Old 12-28-2017, 02:24 PM   #27
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Default Re: No start at gas station

It's 'funny' how these old Fords ran just fine ALL those years, up until the Gov-Mint started telling the oil companies 'how' to refine their products.

Now we have crap gasoline and all sorts of problems.
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Old 12-28-2017, 03:26 PM   #28
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Default Re: No start at gas station

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Originally Posted by fourfords View Post
Problem solved. Points were burned, also found the little carbon insert had separated from the spring of the coil on the bottom of the distributor. Made corrections. Just took the car for a spin. Badda Boom, Badda Bing! Some subtleties in this like making sure the coil is installed directly down so the carbon tipped contact and the copper coiled spring is centered in the cup on distributor. Thanks to all! I learned some cool stuff.
Yep Most "Fuel" problems are electrical. Stands to reasons as the electrical tolerances are tiny so a small variation can cause big problems. So a 10% change in your point gap is going to affect things much more than a 10% reduction on fuel flow -Karl
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Old 12-28-2017, 05:03 PM   #29
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Default Re: No start at gas station

Based on plenty of similar personal experience, with a variety of old Fords, and having wasted plenty of money on fuel pumps, carbs, fuel push rod, and even the odd extra ground strap, i would bet on weak coil. Skip's the man!
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Old 01-02-2018, 08:45 PM   #30
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Default Re: No start at gas station

might want to check out your starter.
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