At my wits end, with this no-start problem!

[H. L. Chauvin]

Hi Bob,

First, you should be highly commended for your patience & your not giving up. No doubt you understand a lot about about all facets of the internal combustion engine & you are very inteligent.

In reading your last statement asking for a "suggestion" & H-E-L-P, with much humility, the following simple tests from former simple mechanics are offered as a simple diagnosis by process of elimination to help to concentrate on an (A) Electrical problem, or (B) fuel problem; or (C) Both.

1. First go to the foremeost source of the internal combustion engine; i.e., the internal combustion chamber where both: (A) Essential spark & (B) Fuel mixture is required. (Forget about the battery ground, battery, distributor, carburetor, intake manifold, fuel pressure, timing, coil, junction box, condenser, shorted wires, points, tire pressure, type of engine oil, etc., etc.)

2. Second, remove all (4) plugs, lay each on its side to properly ground same while being properly connected to the distributor cap, so you can "see" the spark on "all" (4) plugs when the engine is cranked. Concentrate on finding "problems" as opposed to "experimenting" by changing parts.

3. Third, turn the switch to "on", & have someone depress the starter while you, or an "experienced" Model A mechanic observes "proper" spark on "all" (4) plugs. If you have good spark while the starter is depressed, you know you have a good coil, good condenser, clean points, good plugs, & good electrical connections from the battery through the distributor, all the way to the plugs, where it really counts. If no good spark found, one "definitely" has an electrical problem which needs further investigation.

4. Fourth, install all (4) plugs, turn the switch to "off", fully pull out the choke, depress the starter, allow the engine to rotate about a dozen times & immediately remove "all" (4) plugs. Either you, or an "experienced" Model A mechanic can observe if "all" (4) plugs are coated with fuel, i.e., gasoline, with no droplets of water. (If one has droplets of water one may have condensate water in the carburetor bowl which needs to be drained, or water in the fuel tank; or maybe a blown head gasket). If plugs are not wet with fuel one "definitely" has a fuel problem which needs further investigation.

5. Fifth, if the plugs were dry, add about (1) teaspoon of gasoline in each spark plug hole, dip each plug in a (4) ounce or so can of gasoline, "immediately" install plugs, turn switch to "on", & crank engine with starter. If engine now fires a few revolutions, a double check for "no doubt" that one has a fuel problem.

6. Sixth, after these simple tests, the "voodoo" is just about over, whereby one can further investigate: (A) An electrial problem, or (B) A fuel problem, or (C) both.

Having nothing against modern igniton systems & modern fuel systems, it appears one can find more written & posted forum information on how to maintain Model A's when more original parts have been installed.

Hope this H-E-L-P-S!

[gunmetal blue]

Did you try putting gas heat in gas tank. you my have water in the gas. or in the gas tank that blocks the flow of gas.

[jmeckel]

I had almost this exact issue wth my 2 clyinder John Deere tractor. I replaced every part in the electricial system, including all new wire, switch, plugs, plug wire, etc., 2 new carburetors, new fuel lines, checked fuel flow rate, checkd compression, retimed many times, pulled valve cover and checked the tappets, valve timing etc. problem still existed, mostly would not even fire, or when it did run, sounds very bad and died. Finally because there was nothing left to do, I drained out the gas, (the gas was only about 3 months old), and put in new fresh gas...... engine started and ran great. Gas looked good, felt cold when ran on your hand, so it was evaporating, did not smell bad, but would not burn, infact when I dumped a small amount on the gravel drive, it would not light untill I held a match to it and then it very slowly started to burn and then it burned with a yellow flame and black smoke, just like used oil.

I have no idea what was wrong with the gas, other than it was the 10% ethanol junk, some think that the ethanol absorbs water and causes this issue, I do not know, however the tractor has ran just fine since, and I no longer use the ethonal gas.

[mach0415]

If you suspect an electrical issue with all this, checking for resistance in wiring is pointless if all strands are broken except one. When "Ohming out" wiring, it will test good, because it is checked without current flowing. The six volt side of the coil, grounds, and wiring to the distributor needs to be rechecked, because the most accurate way to check an electrical system is by performing a voltage drop test. When loading a circuit, that one last strand of wire inside the insulation will build resistance and impede voltage and amperage through the circuit with current flowing. Weak spark is an example, where voltage and amperage will drop, due to higher amounts of compiled or localized resistance. On a 12 volt system, voltage should not drop more than .2-.3 volts across a circuit. If it shows more, then there is high resistance. My assumption is that 6 volt systems would have a similar drop. I would check all wiring to and from the ignition switch, distributor, and coil to points, using voltage drop tests. You can also check drop across the grounds this way. Once you find it, overlay a wire, or jumper it to confirm. I hope this helps you out. Let us know.

[Fred K-OR]

Originally Posted by steve s

I agree that you should check the ignition switch. The originals are notorious for having problems at their age, and I have had to replace about four of the modern replacements before finally spending the bigger bucks to get a quality one. They can fail intermittently and drive you crazy trying to diagnose. The fact that it ran ok for awhile IMMEDIATELY AFTER fiddling with the ignition wiring is an important clue. Just jumper a wire across the ignition switch lugs, or temporarily twist the two wires together, and give it a go.

Steve S

just read your last note, and see you have a "new" ignition switch. I would still try jumping around it. Continuity testing isn't reliable; a feeble connection might still test ok.

I vote for this answer. Does your coil feel warm with the switch on? If so it would indicate a short. As mentioned above, I would try bypassing the ignition switch and see what happends. Tom W mentioned these checks to me a few months ago and it solved my problem which was the ignition switch.

[Slseacrist]

Sponsored Links (Register now to hide all advertisements)

Maybe a Coil. I am not electrical expert, but I just when through a loss/ week spark. I had burned up two coils before I got my caleague ( auto shop ) teacher to take a look. I had wired mind negative ground 12v to run a alternator. Apparently 12v coils need 8v in or you will burn up a standard coil over time. I got direct 12v ( built in resistor) coil and solved the week spark. With your electrical changes you maybe having similar issues on a 6v system. Sorry this may not be directly helpful but it may spark (pun intended) an idea.

[Popeye31]

get back to basics .Are you using the screw in the front of the timming cover to find top dead center or are you looking in the sparkplug hole? use the pin(screw) in the front of the timming cover. at top dead center make sure the nub for the number one spark plug in the distributor is in the middle of the rotor tip. also check that the points contact has not fallen off of the points . set points to .18 -.22. and check spark plugs for correct gaps .35 . now with the cap off turn the key on and open and close the points with a screw driver if there is a spark put cap and coil wire back on and try to start. if it still will not start pull coil wire out of cap hold close to head bolt and crank engine if you don't get spark change wire, if you still dont get spark after changing wire change coil and condensor. I always change them as a set don't need to but one can make the other go bad. if you still do'nt get spark then you have a connection problem between the points and switch. this can be a broke wire or falty switch or just a bad connection at a screw. also the black wire or the wire that goes to the negative side of the coil should be on the passenger side stud on the distribution block on the fire wall the red wire that goes to the ignition switch should be on the driver side of the distribution block. now if all is fixed you should get a spark if car will not run change cap and rotor. now as far as fule goes check to make sure you are getting good flow through all fule lines I saw a petcock that was parshally cloged and fule would flow but not fast enough to let the car run. I know you have probably checked all of these thing but make a list and check them off as you check the item and I think you will find the issue or multipule issues you might have over looked because of frustration. Like you said these cars are very simple and you just need to get back to basics when assessing issues with them.

[Tom Endy]

Bob:

Were I trying to sort this problem out, two things I would do.

First I would remove the battery and cables and clean the area of the frame where the battery ground strap attaches. This is the most overlooked electrical connection on the car. Out of sight and out of mind. Paint, crud, rust, and powder coating create a poor ground. You can hang ground straps all over the car, but if the battery itself is not properly grounded you will have problems.

Second, I would make up a bypass cable that threads directly into the distributor and attaches with a clip lead to the coil. This will eliminate any loss of battery power through the ignition switch and the pop out cable.

Tom Endy

[PC/SR]

Try disconnecting all wires from the hot side of the coil and run "hot wire" from the battery/starter lug direct to the hot side of the coil. That eliminates all system wiring up to that point. Then check that there is current on the distributor side of the coil, and to the center electrode of the coil. That is a partial trouble shoot of the coil. I may have missed it, but I dont see that you have tested or replaced the coil. The internal wiring can break or short and act intermittently.
I dont know how to troubleshoot an FSI distributor so have no suggestions there.

[1931 flamingo]

Just a suggestion to posters whho are trying to help; Half a dozen of you have told him how to set up and ck a std dist, he has an electronic ign. Others have told him about how to ck for fuel, etc. He's swapped to a weber carb and manifold.

He had a problem, now he has the problem and by changing all these parts, etc, he probably has the orig problem and probably a couple others that have been self induced. He's stated that he's added at least two additional grounding straps and "dremel" polished all attaching points.
Best thing to do would be to reinstall orig dist and carb and intake and start from there, then if it gets running he can change over to elec ign and weber (one at a time). JMO
Paul in CT

[sturgis 39]

Maybe the starter motor is taking all of the juice. I have never hand cranked a model "A",but I have seen it done. I guess you want to pull on the crank. I had a bad starter on a model "T" and the coils were not getting electricity. Some cars actually supply the full 12 volts to the coil when starting.

He probably has had the starter rebuilt. Do you think he is playing some kind of mind game with us. I think this problem has been going on for months.

[Bill Goddard]

On a recent tour we had two cars fail to start and/or run smoothly. Both had to be trailered home - 75 miles. The bottom line was we tried to fix the problems at the scenewith freshly overhauled but faulty replacement parts. Check to see if any of your replacement parts are defective.

[Tom Wesenberg]

Faulty parts is one reason I installed some condensers in my A, then drove with them for a week, and then reinstalled the original condenser. This way I know I have a well tested working condenser for a spare. If you carry a spare carb or coil, I'd do the same with them.

[wi0v]

My car has an 8 volt battery and that really makes it start, worth a try. I know you said you checked the coil, but as an old boat mechanic when they had coils, they would be intermittent, might also try that.

[Bobs29ModelA]

My thanks again to all of you for your ongoing input and suggestions. As we speak, I am already in the process of putting both the original ignition system and Tillotson carburetor back in, just to see what happens.

As far as I can tell, I have probably tested or otherwise checked most everything that has been suggested so far (including taking voltage-drop readings during cranking), without a negative result. The one thing I haven't done yet, however, was the idea of pulling out all four spark plugs at the same time and grounding them out to the block, to visibly confirm that each one will have a spark capable of jumping the electrode's gap. (I've only tried pulling them one at a time and grounding them, not doing all at the same time). I will definitely give that idea a try, once I get everything converted back to it's original configuration again.

I also need to say that, yes, I have been dealing with this disappointing and frustrating issue for a few months now... but no, I'm not "playing some kind of mind game" with anybody! I wouldn't be asking for such help if I wasn't having to deal with these problems, I can assure you. My love of older cars and their restoration/repair goes way back, and I was truly looking forward to driving and enjoying this latest acquisition much more than I've been able to do so far. Hopefully, and eventually, I want to find out what the true issue here is, so I can do just that.

[Brentwood Bob]

Did you intend to use the original coil? By doing the plugs you include everything so that will give you a starting point.

[Mike]

Did you try frsh gas yet ? I once had 2 bad brand new 3 x champion plugs right out the box!!

Mike

[Fred K-OR]

(I've only tried pulling them one at a time and grounding them, not doing all at the same time)

You may also want to pull the coil wire out of the distributor and grounding it on the head as you turn over the engine to see if it sparks. Or you could just ground it and pull the points open and it should also spark when the points spark.

[2935ford]

Just to commiserate with you. I know the frustration. I have a 1919 Dort that ran when I first got it but now.....it turns over but doesn't want to start. It will cough a bit and want to but doesn't. I won't give up on this either. It WILL start!
Keep at it....you will find the cause!

[jkeesey]

Is there a chance the timing has changed? Did anyone check it with the front pin?