What am I missing? 1930 Model A

tjmckenzie said:
UPDATE, UPDATE, UPDATE.....
See attached pictures of wiring. Electrical seems to be right, tested coil and distributor. Thoughts on the wiring?

One thing I noticed but not mentioned before is that the ammeter does not flicker when key is turned but does bounce when turning the car over. Is this a red flag?

Same conditions apply:
Fuel to the intake at top of carb, I even installed a new gasket, still leaks.:mad: See attached photo. Car turns over has dry plugs, no start.

Next up is....compression test and timing?
Click to expand...

If the ammeter is wiggling when cranking - a good thing - means the primary circuit of the ignition is functional. Points, low voltage ignition wiring, ammeter is not open, coil primary, ignition switch are OK.

0 amps with ignition on and motor not running is normal with the points open. The battery has no load unless the points closed, or lights on, horn is on, or stop lamp is activated, etc. You probably are already aware, the Starter is not routed through the ammeter. - 0 amps when points are open is also a good thing, no shorts causing a current draw.

You have spark on the spark plugs, - a good thing. Means that along with the previous above info being good, the ignition secondary is good. Rotor is installed turning since the distributor is driven off the cam shaft which opens closes the points, which causes spark.

So it looks like the ignition is functional.

So seems you have gas getting to the carb since it is leaking. Typically it will leak out the air intake. If when leaking you use a pinky finger around the inside of the air take, it should be dry unless you have over choked while starting. However your plugs are dry, which is confusing.

It could be the carb is completely plugged up. To check for this try when cranking the motor spray some Quick start/Auto starting fluid into the carb air intake. Do nor over do this, this has a tendency to wash the cylinder walls of oil/lube. If it fires/tries to run it is most likely a carb issue.

Or if you have a massive vacuum leak. To check if you have a massive leak put the palm of you hand over the carb intake and crank the motor, you should feel a lot of vacuum sucking on the palm of your hand.

You could try swapping out the carb with a known good one. If you do this swap out the fuel supply to a small separate tank (like a lawnmower gas tank) that has fresh gas. Also drain the carb float bowl in case of water. It is possible the gas is bad if has been sitting for months, and also the A gas tank could be full of rust/debris/water. You do not want to plug up a different carb. If it is the carb you can try cleaning it out and fixing the float valve issue yourself, or have it rebuilt. I recommend Jim Bullock, Texas.

https://jmacarbs.com/

Check back here, or search here on methods/recommendations on flushing the gas tank.

Hope this helps, let us know your progress.
 
If you keep guessing or start replacing things, you'll go nuts trying to figure this out.

You originally said "new spark plugs are firing", but then you immediately said "it seems to me we are not getting spark". Check for spark and report back.

You said ammeter is not deflecting when you turn on the key. That's OK, depending on whether the points are open or closed. Each time they close as the engine rotates, you should see the ammeter discharge slightly.

You say that the plugs are never wet. I would think by now that they would be saturated if you are getting gas. Do a compression check to confirm that the valves aren't stuck open.
 
I am going out on a limb, but here is the proper starting sequence:


1. Turn gas on. If you are leaking gasoline from the carburetor, it is on. Or crack the fuel pipe fitting at the carburetor to see if gas come out.

2. Retard the spark lever. The left lever all the way up.

3. Crack the throttle. Move the right lever down about 4 notches.

4. Turn the mixture control knob counter counter clockwise about 1/2 turn.

5. Turn on the ignition switch.

6. Pull the choke lever all the way out.

7. Crank the engine over about 2 revolutions with the choke out and then let the choke in. Continue cranking the engine.

8. When it starts pull the spark lever all the way down.

9. When it warms up in a few minutes, close the mixture control (clockwise).
 
You did not mention if the car has ever run since in your possession. Yo DO mention gas leaking around the carb to manifold gasket even with a new gasket. You have a Tillotson carburetor which is made of "pot metal". They are fine running carbs when they are 100%. One of the issues that crop up with them is that because of the pot metal composition and their proximity to the exhaust manifold, they tend to warp in between the top and bottom carburetor halves and at the surface where they bolt to the intake manifold. The warpage at the manifold can be so severe that you have a pretty substantial vacuum leak. Others have suggested the engine might be flooded from choking during start up procedure. Carbs with a vacuum leak would need substantial choking to run properly or at all. I'd suggest taking the carb off and checking the top flange with a straight edge to see if it is flat.

Good luck, Bob Bader
 
I talked briefly with Mckenzie and referred him to Modesto area a's.
I have a known good zenith that he can try on the car.
He mentioned that the car was last driven about 10 years ago. Some ignition parts have now been changed.
Car is not ready for the road yet.
 
FROM experience with same problem... Take the carburetor off and clean it out.. Sounds to me like you aren't getting an gas through the carb..
 
Plugged exhaust pipe would do it until the fuel caught and blew off the muffler.
Depend on where the car lived since it went to sleep.
Putting eyes on the car would help.
 
Big thanks to Bob for the phone call. I have attached a few quick pics of car.
-As far as replacing multiple things and then not being able to really track the issue, I like that.
-There is no mouse nest.
-Car was stored for 10+ years in a garage, then car was "cleaned up" with no new mechanical but my grandpa did get it to start. It also got new rims and tires....Then it sat again for around 5 years to where I inherited it this year. I have put new interior, battery & cables, rotor, plugs, belts, fan, fuel bowl, running boards.
 

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It might be helpful to go to utube and watch "How to start a Model A'" Make sure the little lever on the left side of the steering column is all the way up and the choke (GAV) is pulled out when you start it. After it starts move the little lever down to its midpoint.
 
My 2 cents, go back to reply #21 pull throttle down key off put hand over carburetor you have to have some suction there. If not forget the carburetor. The intake has to suck and the suck which sucks fuel from the main jet along with air we breath then the plug sparks and it goes boom so simple. I do the simple, like squirt couple pumps of oil in all cylinders
plugs back in then do the suck test > better or the same. If the same, has to be valves
are not sealing or fully seating probably from sitting so long. Very easy to pop the head and pop the manifold off gaskets are cheap. My next red neck test is to put shop air
in each cylinder listen for air from carb and air from the exhaust pipe thats valves and
probably some air from the oil fill cap tells a lot if you don't have a compression gauge.
Wops I should have said to use shop air before pulling the head.
 
It is really easy to check the compression by cranking the engine over by hand with the hand crank. If it turns over really easy then there is no compression.
 
Another way to check compression is to remove all spark plugs then operate the starter and with your thumb tightly pushing on the plug opening see if there is any air pushing your thumb off the plug hole. If there is then you have some compression. In NO air try pouring a few tablespoons of oil into each cylinder and try the test again. If there is still NO COMPRESSION than you probably have a valve problem. A better compression test would be using a compression gauge. Hope you find the problem as there is no better feeling than hearing a RUNNING Model A. Best of luck a DON’T give up.
 
big job said:
My 2 cents, go back to reply #21 pull throttle down key off put hand over carburetor you have to have some suction there. If not forget the carburetor. The intake has to suck and the suck which sucks fuel from the main jet along with air we breath then the plug sparks and it goes boom so simple. I do the simple, like squirt couple pumps of oil in all cylinders
plugs back in then do the suck test > better or the same. If the same, has to be valves
are not sealing or fully seating probably from sitting so long. Very easy to pop the head and pop the manifold off gaskets are cheap. My next red neck test is to put shop air
in each cylinder listen for air from carb and air from the exhaust pipe thats valves and
probably some air from the oil fill cap tells a lot if you don't have a compression gauge.
Wops I should have said to use shop air before pulling the head.
Click to expand...


You can also try the below before pulling a head. Yours has pretty much sat for at least 20 years. The head may be extremely difficult to pull.

Alternate ways to check valve operation, and without removing the head. Remove the spark plugs, gas off, ignition off, and stick a borescope (they are inexpensive) through the spark plug hole and crank the motor. Observe the valves in each cylinder to see if they are completely opening/closing.

Another check - after draining the motor oil, gas off, ignition off, remove the valve access cover, and crank the motor and observe the valves.
 
UPDATE, UPDATE, UPDATE.....
Bought new carb from @Brentwood Bob. Installed.....We have fire and we have fuel, but.....now we are only getting backfires. Symptom is backfiring, what may be the causes? Thanks in advance and thanks Bob for the carb.

Sent from my SAMSUNG-SM-G930A using Tapatalk
 
tjmckenzie said:
UPDATE, UPDATE, UPDATE.....
Bought new carb from @Brentwood Bob. Installed.....We have fire and we have fuel, but.....now we are only getting backfires. Symptom is backfiring, what may be the causes? Thanks in advance and thanks Bob for the carb.

Sent from my SAMSUNG-SM-G930A using Tapatalk
Click to expand...
Just to add about backfire, it is backfiring out of the muffler, not out carb.

Sent from my SAMSUNG-SM-G930A using Tapatalk
 
Check the compression by hand cranking the engine. If one or more cylinders are down you may have one or more stuck exhaust valves that J Franklin suggested. You should have even resistance on all 4 cylinders when cranking quickly. Do that with the ignition off. Cranking slowly will tell you if you have rings or valves that have a partial leak.
 
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