Today We had a nice day for ride. When I went to start our 16 I think I flooded it had a hard time getting it going when it started it was missing on and off for a while I took off the cool box lid and noticed with each miss one coil would spark a lot at the points like a bad condenser does but in time with the miss after it warmed up it started running good and no sparking on coil what I am wondering is can a fouled plug make a coil spark like that or is the condenser weak?
Could be a temperature sensitive condenser. Old paper condensers as used in Ford coils are always a recipe for problems like this. Your coils will work a lot better (and more reliably) if all the condensers are replaced.
Paul, I believe you are correct. You can test the fouled plug theory by shorting the spark plug to ground briefly with a screwdriver. The engine will run rough 1 cylinder down and you should see similar sparking at the coil points of the respective coil. The primary coil current rises to much higher values with the secondary winding shorted to ground (fouled plug)resulting in greater arcing at the coil points.
It makes sense that the engine smooth's out and coil points stop sparking when the fouling stops occurring. Please let us know what you find.
Jhon I believe all the condensers are original as long as they are working I hate to take them apart , Mike Very nice explanation! I think that's what it was no problem today,except for a small spark on the points now and then that doesn't efect the running car ran good!
Uff da, gorgeous Fords Paul!
Hehe, I see the key on your '16 is "handle up".
I do that too. It took one time of me kicking the car OFF with my foot. :-)
Paul, You're fooling yourself if you think the original condensers are that good. Time for a rebuild!
....and when you replace the condensers, I suggest that having pulled out the tiny nails and slid out the side of the coil, you carefully lever the back face off the coil- the wood next to the old condenser opposite the one with two contacts in it. Then you can lever the condenser out the same way and un-solder the wires. Much easier than digging down from above and less likely to damage something.
There's usually a piece of thick glass in there too. Removing this and the old condenser makes room for the new one. Cut a couple of small wood blocks to fill in some of the rest of the space. Glue the back on again, then melt the old tar and pour in to fix things.
Both glass and wood insulators were used between the windings and the condenser of original, pre-1940 Ford/KW coils. The new "flat" condensers available from the Model T parts suppliers are thin enough that the glass/wood insulators can be left in place. If the old condenser is removed with care, the potting around the windings will not be disturbed. My thinking has been, the less the potting around the windings is disturbed, the better the performance of the rebuilt coil.
Chris & Trent are exactly correct: slowly, carefully lever off the "narrow" side of the box after removing the sliding door. A thin plaster blade works great for this. Makes things so much easier. Personally I haven't had the need to even touch the glass insulator and have found the new cap. fits fine. Use enough wood blocks/space eaters and no extra tar is needed. I notice you have brass top coils. Not sure if the 2 screws closest to the side you'll remove from the box have to come out too. You'll have to see for yourself. Keep in mind, unless you want to, it isn't necessary to re-fill the box with tar but it is necessary to pin the new cap. down.
Chris Trent and Charlie thank you for the good advice I never worked on a coil yet! I do have new condensers I have some old coils to play with that need condensers they spark a lot! David why do you think the cond are bad? just age? I would think if they lasted 100 years why change them? I know I should get the coils set up properly but I have played with them and think the car runs fine. Duey I learned the key trick from a Steve Jelf post!
People with the proper equipment to check condenser leakage will tell you they seldom, if ever, find an old original condenser that does not leak.
What's a "plaster blade"? A putty knife?
Capacitors deteriorate over time. Especially the capacitor technology used in the Model T Ignition coils and given the environment.
Yeah, putty knife. Senior moment.