29 Sport Coup won't fire
 

I have checked the continuity in all the wires. The safety fuse at the starter is not blown, the ignition switch is good. Rebuilt distributor, carb, alternator. New battery, Engine turns over well. Timing has been checked and rechecked but she won't fire. I have spent many hours with local Model A guys but all we can think to do now is scratch our heads.
Any fresh ideas?

Re: 29 Sport Coup won't fire
 

Is the problem fire or fuel ?
While trying to start it can you get fuel to drip past the choke plate ? If so, good.
Have you checked for spark ? Hold coil wire 1/4" from ground and crank engine [ key on] and look for a good spark.
Try these and let us know so we go from there, need to know the basics first.

Re: 29 Sport Coup won't fire
 

It needs fuel, spark & compression. A matter of going thru everything to check.

Re: 29 Sport Coup won't fire
 

as Patrick said we need much more info on the basics..

Re: 29 Sport Coup won't fire
 

There is fuel flow and good compression. No spark from coil wire.

Re: 29 Sport Coup won't fire
 

OK, now we're getting somewhere.
Take your trusty old test light and check for power at the movable point contact when its open and no power when its closed.
The points may just need cleaning, a connection may be loose or grounded. Keep working your way back thru the switch, coil, terminal box, starter. If you have one of those fuse holder thingy's on the starter then take a good look at that.
Some fellas have found a switch contact hitting/grounding on the tank.
A jumper wire across the terminal box wing nuts will eliminate that.
A search should provide all kinds of reading material.

Re: 29 Sport Coup won't fire
 

Sometimes screwing the ignition cable into the distributor too far shorts out the ignition system. The lower plate tang is pushed against the condenser and shorts out the ignition. Screw the cable in as far as it will go without forcing it, and then back it out one turn. See if that helps.
Before you do that, though, unscrew the ignition cable completely and with the ignition key ON, touch the end of the cable against a head stud nut. It should spark. If it doesn't, trace the wiring back at the terminal box to the instrument panel to find out why. Until you get spark at the ignition cable, the best distributor in the world with points or electronic ignition will not fire. If you do have spark when touching the cable, but none at the points, the trouble lies in the connection between the lower and upper plates or a bad condenser. This is assuming you have cleaned the points.
If you have spark at the cable end and at the points, but the engine still won't start, remove each spark plug and lay it on the cylinder head. Re-attach the brass plug connectors between the plugs and the plastic distributor body. With the ignition key ON, hand crank the engine so that each cylinder "fires". There should be a spark between each spark plug's electrode when that cylinder "fires" in the standard 1-2-4-3 firing order. If one or more plug doesn't fire, switch them around and test again. If the lack of spark travels with the plug, that plug is bad. If it doesn't, then the plastic distributor body probably has an internal crack. This will especially manifest itself in high humid or rainy conditions. Repo distributor bodies from the late 1980's and early 1990's were notorious for internal cracks, even when brand-new. Try a different body.
When you checked the spark from the coil, did you hold the end of the coil wire 1/4" away from a head stud nut? A bright flame should jump across between them. If not, trace back to the coil and to the ammeter to ensure connections are good and the coil has juice.
If all of these tests result in the engine still not starting, the ignition system is probably not at fault and I would take a second look at the fuel system. Remove each plug and spray some starter fluid into the cylinders. Replace the plugs and attempt to start the engine. It should start and run for at least a couple seconds. If it doesn't continue to run on its own after the starter fluid has been used up, the problem lies in the fuel system.
But work out the electrical issues first.
Marshall

Re: 29 Sport Coup won't fire
 

when you do patricks test make sure the key is on...

i am not a fan of checking for power by touching live circuits to ground unless i am in the middle of a desert without a test light or meter.

Re: 29 Sport Coup won't fire
 

You mentioned rebuilt distributor. Are you sure it is in good working order?

Re: 29 Sport Coup won't fire
 

Yep, key needs to be on as Mitch said when checking the primary cable and points for power. I thought I said that, sorry.

Another question is who rebuilt the distributor ? I recently ran into one from a vendor that had the primary contact contacting ground and the primary connector lead was/would go open if played with[ required a little extra solder].

Re: 29 Sport Coup won't fire
 

The reason I asked is that I "attempted" to rebuild a distributor and it gave me nothing but problems. So I put in another rebuilt one and it worked fine. The one I had problems with I diagnosed as having "Morning sickness" (this could be a long story). That is when I pulled it and put in the other one. So far have not found the cure for "Morning Sickness".

Re: 29 Sport Coup won't fire
 

I replaced the coil. It came with a small sheet of rubber which I assumed was to insulate the coil from the firewall and clamp. Was I mistaken and the coil needs to ground to the firewall and clamp? What was the sheet of rubber included for?

Re: 29 Sport Coup won't fire
 

I don't know why there was a piece of rubber included but yes the coil has to be grounded to create the high-tension charge to the distributor cap.

Re: 29 Sport Coup won't fire
 

I will try that in the morning. Right now I am going to watch the baseball game.

Re: 29 Sport Coup won't fire
 

Actually the metal case on the coil has no connection to any wire or terminals, so the coil does not need to be grounded. The rubber could be used under the clamp or between the clamp and coil, but I haven't seen any coils like that.

The high tension wire and 2 primary terminals gives you the completed circuit needed for spark to the plugs.

Re: 29 Sport Coup won't fire
 

Re: 29 Sport Coup won't fire
 

Egads I do believe I misled the gentleman, ouch! The circuit gets completed within the coil when the points close and when they open, the magnetic field in the coil terminates. There are various references on the internet showing modern ignition coils with a separate ground wire on them, why, I don't know.

I wonder if his condenser is shot, it would be nice to know if the car ever did run and if presently, he does have lights and horn.

Re: 29 Sport Coup won't fire
 

Yes, the car ran previously and I do have lights and horn. I went thriugh the distributor to check for shorts, replaced and regaped the points and replaced the condenser. I removed the rubber insulator from the coil(if that was what it was supposed to be) and jumped across the terminals in the terminal box to rule out a bad ammeter. I bought the coil from Bratton and I have found that their stuff is as reliable as anything out there. While using the search function last night I saw a post from someone with a trouble shooting checklist and a hand drawn sketch of rhe ignition system but now I can't find the post. Any help on that?

Re: 29 Sport Coup won't fire
 

Loyd turn the key on, open the cap and slightly open the points with your finger if they aren't open already. With a screw driver touch it across the points. You should be able to get a spark. If you have a spark your problem is the body cap rotor or coil to cap wire. Switch them out. If no spark you probably have a grounded out distributor. Either internal or the ignition switch. You may find your lower wire is touching the casting or the lower plate is grounding. Pull out your distributor with the key on and the points open. As soon as it pulls away from the head casting see if it sparks. That's a quick way to see if you have a grounded circuit.

Re: 29 Sport Coup won't fire
 

Ron
I will try that. Thanks