56 T-bird rebuild

[dmsfrr]

Originally Posted by Yotehunter66

Got everything adjusted and the valve covers back. Suddenly I have no spark. Got six volts going through the primary coil windings. I haven't checked the secondary winding resistance yet. New coil wire so I think it's good. I hooked a jumper wire from the coil wire to a spare spark plug and grounded the plug and got no spark. What's the best way to test the electronic pick up?

Can you temporarily put a set of points back in?

Just my opinion, but I use points in my distributor on purpose. Easier to troubleshoot & fix.
.

[Yotehunter66]

I may if I can determine that the module is bad. It's just a magnetic switch. I should be able to disconnect it and hook an ohm meter to it and crank the car and see it its making and breaking contact.

[rotorwrench]

Hall effect switches are breaker less and they are only as good as the quality of the magnetic pickup. Generally they are very reliable. Modules, not so much. The GM HEI is still the most reliable I've ever used in a distributor set up but they are big ugly things (the distributor).

[Yotehunter66]

Pulled the coil off this morning. No resistance on the primary windings. It wasn't an open circuit though. It did show an open circuit though between the primary and the secondary where the coil wire plugs in. Is there a reason to have a 12 volt coil with a resistor knocking it down to 6 volts?

[dmsfrr]

Originally Posted by Yotehunter66

.... Is there a reason to have a 12 volt coil with a resistor knocking it down to 6 volts?

The original coil is actually a 6v coil. The ballast resistor takes the voltage down while the engine is running to help the points last longer and probably keeps the coil cooler too.
There is a bypass circuit, from terminal "I" on the starter solenoid, that provides full 12v only during cranking for easier starting.
Since you're no longer using points and may not have an original coil (?) something else might need to change. Points conversion kits usually have specific coil re-wiring instructions.
.

[rotorwrench]

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There is a reason if the coil is an early type that has the primary resistance to work on either 6 or 12-volt. In the modern era, coils with modern internal insulation can take the higher heat generated by primary coils being designed to run on 12-volt with no ballast. The early coils hadn't evolved that far yet since they felt there was no need when a ballast would do the trick. Ballasts make the coil function more reliable by it operating at lower temperatures. The temperature is no problem for modern coils. They were controlling the current more carefully on the older coils. The voltage is just the carrier. The current is what the coil draws. The ballast does change the voltage as a by product of controlling the current.

I would never have thought that the auto manufacturers would return to the one coil per each cylinder design like they have now. The model T had an arrangement like this except that they were large trembler type coils. Nothing is new under the sun.

A modern coil that is made for 12-volts will generally always have 12V or the like printed on it somewhere. The resistance of the primary coil will tell too as long as you know what the values should be.

[Yotehunter66]

I did replace the coil but it was not bad, since the old one looked ratty. The new one is marked use external resistor. I tested the pertronix and it doesn't look like it's working right. I can get voltage through it but it doesn't change voltage at all when you turn it. Was there a breaker plate originally for the old points that might have been tossed if I decide to go back to points?

[dmsfrr]

Originally Posted by Yotehunter66

... Was there a breaker plate originally for the old points that might have been tossed if I decide to go back to points?

Here's a couple photos of the inside of a '55/'56 Loadomatic distributor (with points) for you to compare to what you have. With any luck the only original parts that may be missing will be the points & condenser and a mounting screw or two.
A ground wire for the points will hopefully be intact. (photo 3)
Photo 4, just for reference, a '56 distributor with what might be a Pertronix module inside, but you can barely see it because the rotor is in the way.

[Yotehunter66]

Looks like mine. Is there a post though that the points sit around?

[dmsfrr]

Originally Posted by Yotehunter66

Looks like mine. Is there a post though that the points sit around?

The points set has a pin on the bottom to locate it on the breaker plate.

[Yotehunter66]

What's the point gap?

[dmsfrr]

Originally Posted by Yotehunter66

What's the point gap?

.014 to .016, or with a Dwell meter 26 to 28.5 degrees. Setting them a hair on the snug side will let them settle in to a good reading. Use a tiny bit of lube on the cam lobes the points wiper rides on.

If you don't have a '56 Ford Car Shop Manual you could use one. I bought a second shop manual for my '55 (on ebay) so I could misplace one and have another to use until I found the first one.

[Yotehunter66]

Well I should have known the parts store would get it wrong. Exact fit they said. NOT! I'm going to take your photos with me to show them what I need.

[Yotehunter66]

Replaced the pertronix with a set of points and a condenser and it fired right up. It runs pretty rough, I think, so I rechecked my wiring and the plugs are correct. All seem to be firing but when I pull #3, 4, 7 & 8 the engine idle does not change like no fuel to the back cylinders. Pulling #1,2,5 & 6 there is a noticable change in rpms. Any thoughts?

[fordrodsteven]

Originally Posted by Yotehunter66

Replaced the pertronix with a set of points and a condenser and it fired right up. It runs pretty rough, I think, so I rechecked my wiring and the plugs are correct. All seem to be firing but when I pull #3, 4, 7 & 8 the engine idle does not change like no fuel to the back cylinders. Pulling #1,2,5 & 6 there is a noticable change in rpms. Any thoughts?

My thoughts are a broken cam but you said you adjusted the valves. You would have noticed there was no lift on those rear cylinders when you were making adjustments. Therefore I would suspect something in that ignition circuit. Maybe swap some plug wires or plugs to see if the problem moves with them. Possibly the distributor cap was not on straight?


If your plugs and wires all check out good can you do a quick compression test on the cylinders? it will tell you of there is possibly a mechanical issue. I would tend to think it's something mechanical because fuel and air would get to all cylinders if it gets to four of them. Spark should also get to all cylinders, if it gets to four of them, if the distributor shaft / bearings are good. I would do a compression test and possibly a leak down test.