30 Zenith Carb

[Quigley1930]

Bill see if you can rig up the can that's on the test stand I gave you. It has the proper fitting for the car inlet. You may gave to get some more hose. Dump what gas is in my tank and try to find some ethanol free gas. The Esso station in Marshall has it. If this cures the problem you can now make it to the show and will only owe me many many nickels

Sewall

[William Kelchner]

Ok Quig I shall work on that. What is odd now with
two different carb's it has done the same thing. Starts,
runs for min or so, has momentary stumble then shuts off
like running out of gas. Now it will not restart. Using regular
gas in the thing now. I shall try again today. Thanks

[Tom Wesenberg]

As soon as it dies jump out and hold the coil wire 1/4" from a head nut, key ON, push the starter rod and see if you have a good blue snappy spark. A weak yellow spark is a problem.

[William Kelchner]

Thanks Tom I'll give that a whirl....

[William Kelchner]

Well what started out to be seeking a cure to my car coughing back through the carb has now mutated to something else. The coughing back through the carb has plagued me since I bought this car 7-8 years ago not sure. At any rate here is what has been done to date:

Replaced carb with known good one
re-timed
new points (orig style)
new condenser
fuel flow looks good to me (photo)
gas cap vented
regular gas
nice blue spark


Now for the last several days and 5 or 6 starts the car runs and after 1 minute 20 seconds dies like it is out of gas. This is a new problem. After the engine dies . with the exception of one restart, it restarts again, runs briefly and dies again from the same symptom. I mean it is like the fuel bowl being drained after a minute twenty seconds. I'm getting ready to chuck in the towel

I do not have a vacuum port on the intake but I'm starting to feel this has to be vacuum related. At this point I keep getting further away from the original problem of the coughing carb.....

[Tom Wesenberg]

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As soon as it starts to die give the choke a pull and see if it picks up again.

[William Kelchner]

Nope tried that, it is intent on shutting down. Was thinking maybe the intake gasket may have gone south but then again it prob would not run for that brief period. It seems like its on a timer

[bunnyc]

I hesitate to make a suggestion here, I'm not as experienced as those who are trying to help. But, I would check the torque on the intake gasket nuts and the condition of the gasket.
BunnyC

[mshmodela]

Originally Posted by William Kelchner

Ok Quig I shall work on that. What is odd now with
two different carb's it has done the same thing. Starts,
runs for min or so, has momentary stumble then shuts off
like running out of gas. Now it will not restart. Using regular
gas in the thing now. I shall try again today. Thanks

So it's not the carb. If two are making no difference. Sure sound like electrical... I am learning these old cars are magnetic for moisture on everything, fuel in the tank, all electrial contacts. Once you figure this out, drive your car at least 3 times a week --your car will thank you by running better... Mine has.... Good luck... And try to use 100% gasoline...

[Mitch//pa]

Does it die out after moving the spark lever down? Then restart after moving the lever back up?
In other words does the spark lever have any effect of when it stalls

[Tom Wesenberg]

I agree with Mike that it sounds like something electrical.

Have you tried another ignition cable, such as the emergency bypass the dealers sell?

It would be a handy item to keep in your tool box, if you don't already have one.

[tbirdtbird]

you'll be a first class Model A mechanic when it is all over .
Too bad the other issue has been there for a full 7 yrs

Are there any club members who can assist you? Do NOT give up.
What is lacking is some rock-solid diagnostics. So far it sounds like stuff is just being replaced........This is very hard for us at this distance. If some of the regulars here could get their hands on the car it would be diagnosed in 10 minutes.
For example, get an in-line spark tester from a NAPA or Oreilly or online so that you can SEE the spark, put it in series with the coil wire, and then when the motor dies you can visually be checking the spark at the same time

Go here, the best 10 bucks you will ever spend:
https://www.amazon.com/Lisle-20610-I...e+spark+tester

Local NAPA, OReilly etc might have it on the shelf

If we all gave up there would be a huge pile of dead Model As in the middle of the Arizona desert right next to the airplane graveyard. You own a piece of history, one that will never be manufactured again...........

if the 4 manifold nuts are tight (30 ft lbs, do NOT overtighten) then it is prolly NOT a vacuum problem

[JOHN CT]

Here's a thought. Could the coil be over heating? In a short period of time. Is that possible?

[Mitch//pa]

I always preach to use a spark tester.. The one t-bird posted is good...snap-on sells the same one in the blue point line for more than double that

[tbirdtbird]

"Could the coil be over heating? In a short period of time. Is that possible?"

If so, it would not cool down quickly enough for the restart he mentions.

The time for guessing is over, the need for hard core diagnostics is screaming from the tree tops.........
Some of these issues are a full 7 years old.........

[Mitch//pa]

If he has AAA premier 200 miles free , I am 190 miles away

[Quigley1930]

Bill, I have the device that Tom mentions. Might be worth a try.

[Dick Steinkamp]

It may not BE the same, but it SOUNDS like the same problem documented in the May/June Restorer.

[tbirdtbird]

you got yours already????

[Dick Steinkamp]

Originally Posted by tbirdtbird

you got yours already????

My bad. I mean the May/June issue. Page 12 "Solving an Intermittent Ignition Problem"