Ford jubilee that will not start

have 1953 ford jubilee switched to 12 volts will not start ;has new wiring harness new 12volt coil points condenser wires cap &rotor . There is a7/16 inch spark off the coil when grounded it is blue color too. when coil wire is inserted in the cap there is no current going to the plug wires .take the coil wire out &replace with aplug volts at the coil wire& ground out aspark plug,there is blue spark .there is 10 volts at the coil when the starter is engaged .this has baffled amechanic of 40 years of service.I am open for suggestions .

A bad cap or rotor will cause that and sadly many new parts now days are not worth buying

Coil wire has spark, plug wires do not?
Is the rotor on right and making contact with the center of the
cap? There is a D-shaped spring clip that goes under that rotor.
The dust cover really should be there too. It maintains proper
spacing and orientation of the cap.

Clip

roter is in place & so is the clip

Have used 3 new caps &roters

Just a shot here, are you using solid wire core plug wires?

Try the old cap and rotor. Also make sure the points are set at 0.025 and that they open at all four lobes of the distributor cam

Make sure the wires on your points aren't being grounded. Hal

Well you have proved you have blue spark through the wires and through the plug. The other thing it takes to start is fuel. I've seen nothing posted yet about that.

You got fire from the coil wire so that knocks out everything in the primary circuit. points; primary wire from coil; condenser.

So now you need to check that the coil fires on all 4 lobes; and make sure your shaft bushings are tight.

Once you do that install the cap and rotor and line up the rotor to one of the plug wire holes. Now check ohms between coil wire post and plug wire post to see if you have a connection. Do this for all 4 plug wire post.
Now put the coil wire in distributor and check ohms from coil end of wire to plug post to see if the coil wire is making a good connection.

Being a mechanic of 40 years you should see where this is going and do the rest on your own without me typing it all out.

I'm betting the rotor to plug wire post on cap is not close enough or the rotor timing is wrong and it is not passing the post when the points are opening. Both of these are cause by inferior china parts.

Had one just the other day on the neighbour's Ferguson. Take the cap off and turn the engine over while holding the coil lead over the rotor. See if it arcs over to the rotor. If it does, rotor is earthed.
He had good spark from the coil but nothing to the plugs. The rotor was shorted.
Rx

Is the rotor turning? Sheared pin on dist shaft, or stripped shaft gear?

Have you tried pull starting it? My 450 only fired after you let off the start button, she just wasn't getting enough power to run the starter and ignition circuit at the same time, she would roll start out of the barn if I could get it moving. I fixed it by getting a new set of battery cables and cleaning up all the connections.

Nate

(quoted from post at 12:45:12 12/13/14) have 1953 ford jubilee switched to 12 volts will not start ;has new wiring harness new 12volt coil points condenser wires cap &rotor . There is a7/16 inch spark off the coil when grounded it is blue color too. when coil wire is inserted in the cap there is no current going to the plug wires .take the coil wire out &replace with aplug volts at the coil wire& ground out aspark plug,there is blue spark .there is 10 volts at the coil when the starter is engaged .this has baffled amechanic of 40 years of service.I am open for suggestions .

Click to expand...

from the above testing....the rotor must not be lined up with a cap terminal when the coil 'fires'

first, static time it so you are sure the rotor is pointing at a cap terminal when it is supposed to.
(distributors get turned..and even clamped down, the actual clamp can slip sometimes)

double check that power pass thru on the side of the distributor. An intermittent short there will drive ya crazy.
During testing all will be well sometimes. other times...nothing.

and as said, on Fords, make [b:d2e022e342]sure[/b:d2e022e342] you are getting the right parts. Distributor dust cover/caps changed year to year.
some dust covers are just dust covers, others are cap spacers and aligners.
forget a spacer where one is needed=broken stuff.
put a spacer where one doesn't belong and the rotor tip to cap terminal might be too far apart.....

and like the other poster...if it ran before...I'd static time it, put the original stuff back on...and see. If it runs then, a very careful comparison of the new stuff will find the culprit/difference.

I know you are dealing with new stuff and you would catch it, but moisture in the cap will do that too.
And do some testing in dim light.
If that high energy pulse can find an easier way to ground than where it is supposed to go......it will...
sometimes amazingly so. had one coil..arc came from under wire boot, traveled across the top of the coil and went to one of the coil stud terminals. Watching it as the tractor was still running raggedly....thought..That's impossible..too far..but, there it was LOL

ps as you are sorting it out..
I know you have a spark tester in your toolbox.
hook it up at an installed plug, so you know when you have it fixed and it is sparking in the only place that really matters...
testing, hand cranking, starter turning.....when I see the lightning at the tester, plug in under pressure...I know I can cross ignition off the list

I had the 4 sided nut on the dis. shaft on a 600
series ford turn so it was firing between the plug
posts. I turned and pin pricked it into position
as a temporary fix. No idea what caused the nut
to come loose. The way way to tell was I released
the cap hold down springs and turned the cap while
cranking and it started to fire.