No spark at the plugs

[burner31]

Originally Posted by Jim M

Some time ago I had the same problem that your are having and it was EXACTLY what CT Jack has described. Took me about a week of frustration to figure it out! (and a few shots of Jack Daniels...lol)

Ignition switch cable should be finger tight/snug into the distributor
Some crank it down so tight it grounds and then wonder why it won't start

[Daba]

Absolutely correct I changed the cap rotor and distributor body and that did the trick thanks for all your help. I look forward to needing you again soon.
Daba

[Daba]

Absolutely correct I changed the cap rotor and distributor body and that did the trick thanks for all your help. I look forward to needing you again soon.
Daba

[nkaminar]

As I said in post #16, there have been reports of bad housings. It must be a manufacturing issue or a breakdown of the conductors. Glad you got your truck running.

[ndnchf]

Glad it was something simple!

[Daba]

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So I had it running for a bit a few times. I finally took it for a short ride around my yard. It sputtered a couple times and then BANG backfire and stalled. So I rechecked the timing and now it spins over but won’t pop off ?? Any suggestions. I have spark at the point and spark at the coil wire coming in. It has gas and gav turned 1/4 turn, Maybe it’s flooded not sure. I’ll try again tomorrow.

[nkaminar]

It could be that the distributor jumped timing 180 degrees. This can happen if the shafts are worn and the distributor shaft slips and re seats 180 degrees out. The slots are offset so this doesn't happen unless things are really worn. I did happen to me once many years ago after hitting a bump on the road. The distributor can then jump back so the timing will return to normal. This is an unusual problem so it is likely something else. Backfiring can be caused by a lean mixture. If the fuel flow is restricted the carburetor can run low causing sputtering and backfiring and stalling. If you have an aftermarket filter in the line this can be the cause. Others have reported a similar issue when there was something in the tank that would block the flow intermittently. If the line into the carburetor is pushed too far in at the fitting this can also restrict flow. Restricted fuel flow can also be caused by blocked or missing vent hole in the gas cap.

[Ernie Vitucci]

Good afternoon...The backfire could also be a condenser that is at the end of its life. They are ok cold, they start to fail as they warm up. Don't get a cheep one...get a good one from Bratton's, Arizona Model A, or another of the major suppliers...Ernie in Arizona

[aermotor]

I have had the same problem of no spark at the plugs. After starting over several times with the timing procedure it turned out that the point gap was too large. After setting the gap when I torqued the screws down the points moved and like a dummy I didn't check the point gap after torquing the points down.

John

[The Master Cylinder]

Originally Posted by aermotor

I have had the same problem of no spark at the plugs. After starting over several times with the timing procedure it turned out that the point gap was too large. After setting the gap when I torqued the screws down the points moved and like a dummy I didn't check the point gap after torquing the points down.

John

Are those modern points? I can not see how "torquing the screws" would change the gap on original type points.

[lrf]

On a tour recently, we were on the freeway about 50 mph, pulled off on an offramp and the "A" quit, tested: no spark to plugs. Looked at the distributor cap and the carbon piece was missing from the cap. Replaced the complete distributor and she ran. At the next seminar, the carbon piece was found jammed and grounding the points. These cars are so simple and yet confounding. Love my "A"!

[aermotor]

Originally Posted by The Master Cylinder

Are those modern points? I can not see how "torquing the screws" would change the gap on original type points.

With a lock washer under the screw that is next to the contacts the position of the lock washer digging into the fixed points arm and the screw try to move the arm towards open or close.

[Daba]

I’ve been trying all morning and it won’t pop. I have rechecked the timing and it’s spot on, I have spark at the points (modern) and the coil fires off when I open and close the points. I have great gas flow. I reluctantly tried ether in one of the spark plugs and in the carburetor and still have no bang. it seems to me like it’s a spark problem.

[ndnchf]

All that cranking and fuel into the cylinders may have washed all the oil off the cylinder walls, resulting in a loss of compression. The rings need oil to seal well. I've seen this happen. Try pulling the plugs and add a little oil to each cylinder.

[Daba]

I forgot to mention that it sat for a few years before I started trying to get it going again. But it was starting 4-5 times before I tried to move it around. A when I was going down a slight grade and turning to the left it started to sputter and then pop backfire now it won’t start. I’m confused because I have gas and spark. The last message said to add oil to each cylinder how much would you recommend a couple caps s or so??
Thanks again

[ndnchf]

You don't need a lot of oil. Maybe a teaspoon or 1 squirt from an oil can. Enough to get some oil on the cylinder walls and the rings to help them seal. It'll smoke if it starts, but that will burn off quickly.

[Certimafied]

Im just going to throw a few things out that I have experienced in the past with old vehicles not necessarily model a's.

Be sure your cap can touch the rotor. Be sure the carbon piece is in the distributor top and the rotor top is springy.

Check the gap between your rotor tip and the distributor body.

Check the condition of the electrodes inside the cap and where the plug straps/wires attach. Corrosion will cause high resistance that can cause some funky things.

With the top off the distributor and the rotor still in place on the distributor shaft, hold the high tension coil wire just above the rotor and spin/crank the engine over. Spark should not want to jump to the rotor, if it does the rotor is grounded/Bad.

Pull the cap off the distributor and the rotor off the shaft grab the distributor shaft, give it a forward and backward wiggle there shouldn't be any, or very minimal. My A had too much play and would give an erratic idle and hard start sometime. If this is the case it seems it should still try to pop at some point though.

A Different A I worked on some time ago had the timing rod pop off at the steering column. The issue didnt arise until trying to restart. It looked good initially at the distributor until I looked from the other side. Even if your rod is attached still be sure it is in the correct setting for starting.

My A had a condenser fail once, however that resulted in No spark.

There is a possibility maybe that your high tension coil wire is faulty. In situation it has a break in it but when you hold it for testing it works. If you have a multimeter you could check the resistance of that wire. Solid core wire should have minimal resistance.

I had a weird thing once on a car where the coil had a break in it at the nose where the high tension wire plugged in and the spark would jump to one of the primary posts of the coil instead of go down the wire. You can see that in the dark pretty clear usually. you may even hear the pop from the spark.

Be sure your plugs are dry and clean, may as well check the gap while your there too.

Good luck with everything! I can understand your struggles with the cold, fingers just don't like to work under a certain temperature!

[nkaminar]

Daba, The bottom line is that you must have sparks at the plugs at the right time. Take the plugs out and lay them on the head. Leave them hooked up to the distributor. Pull the timing lever all the way up. Turn the ignition on and hand crank the engine over slowly. Each plug should fire as its piston gets to the top. You can know when the piston is at the top of the compression stroke by sensing the compression with your thumb in the spark plug hole while someone else cranks. Once you sense the compression on one cylinder you can just use the timing sequence (firing order) to know when the other pistons are at top dead center. The timing sequence is 1-2-4-3.

Ndnchf was alluding to a lack of compression. You can test the compression by hand cranking the engine over. There should be resistance on all 4 cylinders as they come up on compression.

[Rob Doe]

I just read through this entire thread, and I know you said the timing is spot on, but there have been threads on here where it turned out to not be correct for various reasons.

When you remove the timing pin and find the detent in the cam, is the piston at top dead center of the #1 cylinder. You can see this by looking through the spark plug hole.

If you then stand on the right side of the car, looking down at the distributor, is the rotor aimed at the #1 distributor body electrode/contact/terminal? The rotor should be aimed approximately at the right front headlight.

The spark/advance/retard lever must be all the way at the top when you are setting the timing. You can't see its position in this photo, but under the left side of the distributor body, the lever should be all the way toward you in the opening of the distributor body.

[Daba]

As I said earlier this truck was sitting for years before I got it. That being said I just added fuel and never looked in the tank after scratching my head for a few days I drained the tank and found water and crud. After cleaning out the tank and carb bowl if started right up. I apologize for my stupidity and appreciate all your help. This place is a wealth of knowledge and would be lost without it.
Thanks Daba