Electrical/Timer issues

[TheSaintDiscJockey]

After installing a new timer and roller, and a new wire harness, I am getting a buzz on 1,2 and 4.
3 is not buzzing.
The commutator is properly wired.
Connections to the corresponding coils are correct.
I had a short installing the timer, which prompted me to buy a new harness.
An exposed, frayed wire may have caused it or an engine pan bolt that the timer came in contact with.
As I mentioned, the harness was replaced, and I reversed the bolt so that it is head up.
There is no possibility of a short in the timer area.
I tested the coils by switching them around.
They are all good.
Same with the spark plugs.
As I said, 1,2 and 4 fire.
3 does not.
I double checked the coil box itself.
The box contacts appear in good shape.
When it shorted, a noticeable sound could be heard, and a puff of smoke came from the manifold around the 3rd cylinder.
I do not have the generator connected.
Today, I was turning the crank to hear which buzz coils were firing.
The roller is spinning freely.

I'm stumped.
Any suggestions?
Many thanks in advance!

[Norman Kling]

With the ignition to battery, put a screwdriver to the small terminal on the coil box for number 3. If it buzzes, the problem is in the wiring or the timer, however if it does not, you might have a bad connection inside the coil box. If it buzzes but no spark at the spark plug, you have a carbon path inside the coil box. What kind of timer do you have? Is the plate in front of the timing gear exactly centered on the camshaft? Some timers will not work propery if not centered. A New Day timer works best if it is not centered, but the roller type might be missing the contact for number 3. One other thing not related to the electrical system, is a sticking or burnt valve. Have you done a compression check? It should be almost the same on all 4 cylinders. If Number 3 has low compression, you could have an engine problem. Also one more test. Swap another spark plug with number 3. If it is still the same your spark plugs are OK, but if the misfire moves to the cylinder where you moved the plug, you have a spark plug problem
Norm

[John kuehn]

When you have the engine turned to when the no.1 cylinder wiggle the wires, jiggle or what ever. Loosen the nuts on no.1 terminals and make sure there is good contact.
Maybe carbon tracking in the coil box? Rebuilt coil box or original.

That happened to my 24 Coupe once and checking this that over and over I found it was coil box barely loose nut on the coil box wire to the plug. Your is something simple too I’ll bet.

If you still have your old timer put it back on and see what happens. It won’t take to long to try.

[TheSaintDiscJockey]

Norm, I have the roller style timer, used by Ford.
( T-3165 in Snyder's catalog)

[TheSaintDiscJockey]

Thanks for the tips.
What exactly is carbon tracking?

Will do some research...

Will check the #3 spark plug wire tomorrow morning.
Didn't check that.
.

[Humblej]

Did you swap out coil no 3 with another coil?

[TheSaintDiscJockey]

Yes.
All coils are good.

[Oldav8tor]

We recently discussed coil box carbon tracks <viewtopic.php?f=2&t=38750>

If you have a wood coil box you might consider replacing it with a plastic kit from Snyders.

Are you sure the contacts inside the box are sprung out enough to make contact? That can make a coil misbehave.

If you have a Volt Ohm Meter (VOM) you can check the circuits and different points to make sure the voltage is getting where it needs to be.

Good luck!

[TheSaintDiscJockey]

Many thanks for the suggestions.
Will further explore.

Scott, thanks for the pm.

[speedytinc]

Many thanks for the suggestions.
Will further explore.

Scott, thanks for the pm.

#3 ISNT BUZZING.

Coil has been switched. The problem is in #3 coil position.
Ground out #3 coil box upper terminal with the key on battery.(as Norm suggested) If it busses, problem is between this terminal & the timer.
If It doesnt buzz, carefully check the terminals & contact connections. Check the inside finger contacts.

[Arbs]

An easy thing to check is continuity with a cheap multimeter that has that function. Check each wire, and connection. Compare continuity with a working circuit to the non-working.

A connection or wire with continuity doesn't guarantee it will work under load, but broken continuity in a place where you should have it is a good indicator of a problem.

It's late, or I would go into more detail.

FWIW, I ended up replacing the wood in my coil box with plastic, cleaning all connections with a wire brush and readjusting the tabs mentioned earlier. Resoldered a connection too. Now I feel my coil box is working well. I also replaced all spark plug wires and the wiring harnesses. That and many other tweaks later and I have a good running T.

Post some pictures so we can see what you have to work with.

We're all in this together.

[TheSaintDiscJockey]

First off, many thanks for the kind and helpful suggestions.
As I always say, if a question can't be answered on this forum, the question doesn't exist .

Went through the coil box, spark plug wire, etc., trying this and trying that.
I was still in search of the answer to the elusive mystery of the non-firing #3 coil/commutator contact.
Worked my way down to the commutator and took it off for further examination.

It then became instantly apparent that the roller spring had come off!
The large "ear" of the new roller was not angled sharply enough to hold the spring.
Either a reproduction design flaw or something I should have known to correct when I bought the new commutator mechanism.
I bent the ear back a bit so that the spring from the old roller fit nicely on the new one.
Reinstalled the commutator and went through the firing cycle with the crank. 1,2,4 and 3 all fired as they are supposed to.
Sometimes it's the really stupid stuff that goes wrong...
Pictured is the old roller.
I know the spring was on the new one and working properly when I initially installed it several days ago.

[John kuehn]

It’s usually somthing simple when looking for a miss or a non firing cylinder! Glad you found the missing spring issue!
Be aware a T owner can “over think” these things and think in todays terms about vehicle engine issues.

[TheSaintDiscJockey]

Thanks, John.
Though poking around the coil box made me realize that some new hardware should be in the offing, after I get done with the pawl installation on the emergency brake.
That hardware looks pretty tired...

[Norman Kling]

Great. Good for you that you found it!
As for the brake Paul. That reminds me of a Mr. Curtis who was our home vegetable man in the early 1940's. We lived on a hill so he would go to the top of the hill and then make his stops as he came back down. Not a steep hill but one which could cause a T to get out of control if parked with the engine running and the brake slipped forward. He had a corrigated cardboard on the floor in front of the lever with a stick holding the parking brake from slipping. Well one day right in front of our house he parked and while out of the truck, the stick slipped which sent the truck going down the street with him running after it. A pole finally stopped it. Only time we saw Mr. Curtis again was when he came walking around the neighborhood to collect some money owed by some of neighbors. He was about 77 years of age at that time. He had some kind of problem where when he started walking forward he could not stop until he came to a tree or fence. I think the truck was totaled. I wonder if anyone got any of the fruits or vegetables.
I said all that to tell you that Paul on the brake lever is very important. It is good to pinch the handle until it begins to get tight and then only move it about one click to set the brake. Or if you want neutral, just pinch the handle until it is in the right position. That will save wear.
Norm

[TheSaintDiscJockey]

Excellent, cautionary story!

[Dan Hatch]

Not sure what year you got, but reuse the spring contacts in Coilbox. If you bolts that hold them in are steel, replace them with some brass ones from an earlier car. Use electrical lead solder and solder the contacts to the heads of the brass screws.
Makes a big difference.