65 Comet dies while driving

Maintenance/Repairs
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I could use some help diagnosing something on my 65 Comet 202. I’ve been through the vintage Ford forums and can’t seem to nail the problem down. I listened to Car Talk all the time with my Dad growing up, so I figured if any group could help it would be this one.

Quick car background: 65 Comet 202, 408W, 4 spd Toploader, MSD RTR Dizzy and Blaster Coil w/ resistor bypass, Quickfuel 750 Vac secondary, otherwise factory wiring/plumbing

First, I was getting on the interstate a few weeks ago, put it in 4th to cruise with traffic and the car just…lost power. It happened pretty fast, but I think the car was revving with the accelerator it just wouldn’t go. Called my car guy, got it up on the trailer, the clutch linkage somehow had worked its way out a few turns (which is weird because normally under load they would want to get shorter, right?), drove it off the trailer and home. This may have been a completely separate thing, who knows…

Yesterday, I decided to take the Comet to work because I didn’t have to bus the little one across town. First time it was out since the last issue. The car did fine from my house to work (about 15 miles, mixed interstate and street level) and then died as I was coming into the parking lot. I pulled into a space, restarted it, then drove the last few hundred yards to where I normally park. I was starting from a stop, possible I did something stupid, but it didn’t feel like it and I decided to drive to my car guy’s shop (5ish miles) over lunch just in case. In that 5 miles of surface road driving it died about 7 times. When I say died, it’s like I turned off the key but the engine was still turning because of the momentum of the car. No pedal response. Sometimes it would restart in neutral while rolling, but mostly I’d have to pull over, stop, crank and restart. It would normally happen after I get through 1st and 2nd, when I put it in either 3rd or 4th to maintain speed. Seems only to happen after the car is at temperature.

Here’s what I know so far: It’ll idle fine pretty much indefinitely, regardless of engine temp. Wire from ignition to coil is tight at both ends. So is wire from solenoid to coil. Wiggling the key while idling or smacking the solenoid doesn’t affect it. Jumped battery + to coil + and still happened (not in dash wiring). All grounds look good. All spark plug wires are tight on cap as well as plugs, same thing for center coil wire. I do have a rally tach, but because I have an MSD RTR dizzy and Blaster 2 I use one of those converter boxes so the tach itself is not inline with the ignition. Even so, pulled it just in case and taped off the lead…no love. I do have gas pressure at the carb, maybe a little low, but it revs to the rev limiter on the dizzy just fine as long as it’s not under load. Replaced fuel pump anyway just to be sure. Gas filter just north of the tank is glass and perfectly clear.

I’ve got to go to the shop after work today. I plan on just swapping the coil and putting a points dizzy back in with a ballast resistor to see if I need to send stuff to MSD to be repaired. WHAT AM I MISSING?

Thanks,
Joel

2

I would think if it were loss of spark you would get backfires on restart, because it would be putting raw gas vapors into the exhaust system.
I suspect fuel flow is restricted somehow and you’re emptying the fuel bowl.
It can keep up with idling but not cruising.
Does this carb have a little filter screen where the fuel line attaches?

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The car sounds more like a collection of Hot Rod magazine terms than an actual automobile.

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Circuitsmith: I was thinking something similar, hence the new fuel pump. Unfortunately, when sitting still a revving the engine the fuel level looks good (Quickfuel has the nice sight glasses in the bowl) and the psi gauge I put between the prim/sec reads minimum of 4 psi. The filter is between the pump and the gas tank under the car. It’s one of the glass variety and it looks brand new inside. If it were a blockage in the tank itself, I would’ve expected SOMETHING to make it to the filter. Not to mention, it lets me burn rubber through first/second…it’s just when I go to cruise that it cuts out. And then it cuts out regardless of throttle once it restarts.

Rod Knox: I worked on the car for 15 years, and made a point of only using the best everything in the car. It also has vintage air that I don’t even use because I like hearing the Flowmaster exhaust note with the windows down! :smiley:

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Try running her with the gas cap OFF of the tank. See what you get.

I havent decided whether this is fuel or spark and I am getting a little confused (tho I do that to myself often)

Did you just recently put the newer distributor on the car? Is that why you are going to go backwards to a points style setup? Points style really don’t get you anywhere…the newer style distributor was better on all levels. Im wondering why you would be reinstalling the old distributor so quickly.

Let me know how it runs without the fuel cap on the tank

Blackbird

6

What happens to the fuel pressure right before it dies? When it dies, pop off the air cleaner and see if the carb has gas in it, and that it comes out when you pump the gas. If it does, then it’s spark, I’d think.

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If the intake’s exhaust crossover is not blocked the intake could be too hot. That problem would be most apparent at higher speeds especially if there is any relative difference in the exhaust back pressure from side to side.

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Revving the engine at standstill doesn’t use enough gas to challenge the fuel supply system.
The little filter screen I mentioned would be in addition to the main filter.

Try disconnecting the fuel line from the carb and put it in a beaker or other suitable small container.
Have a helper turn on the fuel pump for, say, 5 seconds.
See that you get a good flow of fuel, at least 4oz in 5 seconds.
You could also set up the fuel pressure gauge to be readable while you drive, but that’s a lot more involved.

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First off, I like the OP’s use of the term “dizzy”!

What the problem is, is hard to say. But it pretty much has to be either spark, fuel, or compression. And since it seems to run ok otherwise, likely it isn’t compression. Intermittent problems like these often turn out to be electrical, so I’d first suspect the ignition system, possibly a heat related failure. On the fuel side, I’ve had a problem like this before on my 70’s truck, and it was the fuel inlet needle valve workings in the carb that was sticking. So the carb bowl sometimes would empty of fuel and the engine would stall. But it would often miraculously fix itself after a few minutes of cranking. I think the cranking may have done some extra jiggling which broke the needle valve free.

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@georgeSanJose Dizzy is British slang for distributor.

I’d lean toward fuel starvation due to a plugged filter. I also like the sticky float needle theory.

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Time for new plugs, my wag. then look at the condition of the plugs and report back

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If you have ignition points disconnect the vacuum advance and see if it stalls again. If it doesn’t stall, check the wiring the distributor for fraying or looseness. You probably don’t have that problem. If your points are new looking, run a points file through them because contact may be minimal.

Check the condition of the negative battery cable where it attaches to the wheel well. That is unlikely to cause problems if your starter always works but hey, it’s a 65 Comet and I didn’t have many starting / running problems with my 65 Fairlane back in the 70s. If you have standard issue plug wires, which you probably don’t, change them because Fords used to eat ignition wires.

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He has a new electronic distributor with no points…but has mentioned re-installing the old style distributor…which will be a total waste of time. The OP hasnt responded in a while and methinks he is wrenching and testing at this time. We should hear from him soon with either more symptoms or the Silver Bullet. Stay Tuned I feel an update a coming.

Blackbird

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I would hook up a vacuum gauge. If the reading is low, it might suggest a restricion in the exhaust system. If it is erratic, there might be a vacuum leak. You can short out each plug one at a time and check for a weak cylinder. A,cylinder that doesn’t change the vacuum reading when shorted out is a weak cylinder. In the old days we learned that a vacuum gauge is your friend.

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That is IF the OP knows how to read a vacume gauge or Not… My money is on Not… Took me a while to get good at it and I’m still learning how to decipher that simple tool. Simple yet able to show so many different variables. Its almost a Lost Art these days methinks

Blackbird