#1 Plug will not Fire

[RVA23T]

I cannot get a plug to fire/spark in the #1 cylinder. There is spark at the plug and can get an arc when shorting it to the cylinder head with a screwdriver and it does not change the rpm nor rough/misfire when 1 is shorted out.
Car is a 23 Touring has a 26 engine block and transmission.
Here is what has been done:
1. Installed I-timer and adjusted the timer rod.
2. All 4 coils have new correct capacitors (from Langs) installed and adjusted on my ECCT.
3. installed new insulator washers on the coil box insulators
4. checked all contacts in the coil box for positioning / alignment.
5. changed plug wire with spare and same issue plug will not fire
6. tried other plugs both installed and outside the head (grounded the head and or bolts) Motorcraft, Champ X, Edison plugs.
7. traced and checked timer to coil harness/wires for position, isolation, and not contacting ground from timer movement.
8. made sure nothing inside timer housing insuring it is dry & clean.
9. when hand cranking the engine (plugs not installed but wires attached and plugs resting on the head) to set the I-Timer, had both
suction and compression at the hole.
Ran fine after I-Timer install for 20 miles on Friday and for 30 minutes Saturday between idle and test drive after adjusting the timer rod. While/after cooling down, washed the car had some water on the block and in the spark plug bowls and, on the firewall, there was some overspray but the firewall was not washed nor hosed down and used compressed air to dry off block/engine compartment and blew out the coil box firewall holes to make sure it was dry and no water shorting things out. Could not get it start, opened the carb drain and the tank spud drain to make sure no water. I was sure I was getting fuel from smell but having just had covid smell is still not back fully, shot with starting fluid and got no reaction, check connections at firewall and timer got it to fire on 2 and 3 but not 1 and 4 which allowed me to get it back into the garage.

I am missing something but i can't think of where to go next except a compression test. Any suggestions would be appreciated.

[speedytinc]

The plug may not be firing under compression. The old champion plug tester tests plugs under compression pressure. I had a plug that would fire intermittently @ .025 gap using a champion tester. After resetting the plug gap to .023, she functioned properly. Weak plug.
Check the gap & try again unless you can get access to a plug tester. You can switch plugs to see if its the plug or the hole.

[TXGOAT2]

(1) Check engine compression using correct procedure. Check valve springs. Try a new spark plug. Correct whatever is causing the engine to get wet. Check for intake manifold leaks. If your engine was sprayed with rusty water or with anti-freeze, you may have to wipe ALL residue off of and out of electrical parts with a clean damp rag to prevent shorts. Be sure to carefully check timer wiring along its entire length, paying special attention the wires around the timer itself.

[John kuehn]

It’s probably something simple. Try not to overthink what the issue is. If you can park your car in a dark garage start your car and check around the coil box and any other wiring. Move the wiring around to check for any arcing. Remember a T ignition system isn’t a computer.

[Mark Gregush]

" Remember a T ignition system isn’t a computer" Maybe not, but he is using an I-timer.
He states he has tried different plugs/sparkplug wire, so that should eliminate the those as the issue.
Did you remove the timer and make sure it was dry?

[KWTownsend]

Swap out the coil with from a different cylinder and try it. Then swap out the spark plug from a different cylinder and try it. Did the problem move?
If it is still number 1, check to make sure the contacts in the coil box are tight (bottom too) and make sure the piece in the top of the coil box lid holds the coils down.

Running it in the dark is a good way to look for stray sparks.

Make sure none of the bolts or timer rod are shorting anything out in either retard or advanced positions.

You might have some carbon tracking going on in the coil box. It might be time for a fun project coil box kit.

Good luck. Let us know what you discover.

: ^ )

Keith

[Charlie B in N.J.]

I consider myself the "do a compression test" guy even if no one else does but while it's not a bad idea to get some readings I'm not sure it'll answer any questions as far as your problem goes. Sorry to say I think the missing of 1 and 4 after the wash is related to the timer. You say "26 engine? assuming the coil box is on the engine or did you stay orig and keep it inside? As Yul Brenner said in the King and I "Is a puzzlement". Replace the plugs and use a slightly smaller gap at least to eliminate the one thing that seems not to have been changed.

[RajoRacer]

I recently re-wired a '13 with a "new" commutator loom that was actually for a '15 and had no fire to # 1 - when the loom was made, the black wire for # 1 was somehow switched to the headlamp black wire - had to check continuity to figure it out !

[Norman Kling]

Did you get any water on the timer? If you are getting spark to the plug, but not when running, then you could very well have burnt a carbon path into the wood in the firewall or the coil box. if this is so, then the current will take the path of lowest resistance. It is harder to jump the gap under compression, and it might be jumping somewhere in the coil box. Also take the advice above and make a smaller spark gap in the plugs.
Other than that, I can only think of two other things. One would be a stuck or burnt valve which will not let you get fuel or compression to that cylinder, or an intake manifold leak which will make the mixture too lean on that cylinder.
I know nothing about e-timers except that I would recommend that you always have a spare working timer with you, because electronics can go bad at any time. But I would also recommend the same thing with an old fashioned timer as well.
Norm

[John Codman]

The plug may not be firing under compression. The old champion plug tester tests plugs under compression pressure. I had a plug that would fire intermittently @ .025 gap using a champion tester. After resetting the plug gap to .023, she functioned properly. Weak plug.
Check the gap & try again unless you can get access to a plug tester. You can switch plugs to see if its the plug or the hole.

As was mentioned by the above post, all you need to do is swap #1 plug with any of the other three. If the misfire moves with the plug, you need a new plug; if it doesn't, then the problem has to do with #1 cylinder. I would swap the #1 coil with another and see if #1 fires, if it does there is a problem with the #1 coil. If #1 still does not fire, then the problem is in the wiring between the coil and the spark plug, I am referring to the low voltage circuit) or a bad contact in the coil box to the #1 coil. Why did you replace the timer? There is such a thing as new defective. Go for the simple stuff.

[RVA23T]

Thanks for replies here are some answers to your asked questions and shared thoughts.

speedytinc: I do have access to a plug tester that uses compressed air to test and has the "sand" blaster feature to clean the plugs as well. I will get My dad to dig it out and test all of them.
TXGOAT2 [color=#0000FF]Mark Gregush[/color] : Water was involved because I had to flushed radiator (block sat open all winter and spring while I worked on trans change so there was some new rust lose in the radiator) and from general washing, any leaking was corrected & when rinsing off the engine I tried to avoid the fire wall with any direct spraying. Timer has been removed, wiped off and out and found dry. Timer harness is new installed this spring while replacing transmission, driveshaft and rear diff.
John Kuehn: I will add this to the diagnostic list.
KWTownsend: coils, wire and plugs moved/swapped and it stays at the #1 position. pulling out the Coil Box and inspection added to list.
Charlie B in N.J.: Coil Box is through the firewall as a 23 should, Block has a 1926 number and has wide band brake drum. Your are the 2nd to suggest smaller plug gap so this is added on as well as the compression just to know.
RajoRacer: going to get the ohm meter out and retest the new harness& plug wires against the old harness for continuity and resistance.
Norman Kling: Thinking valve issue also but plugs were also not firing out of cylinder, the compression test should show this and rechecking with the roller timer added to the list.
John Codman: Installed I-Timer for the maintenance free factor vs a roller. Going to pull coil box and really inspect. I have spark at the top of the spark plugs just not through a plug at #1 and the 4vcoils all test excellent on my ECCT.

Will update as I go along. Thanks again

[Mark Nunn]

Here's a stupid idea. Do you have dirt daubers in your area? One could have blocked the intake passage. It could happen.

[Aussie16]

Remove side cover plate form the engine and check valve springs, collets and keepers. you may have dropped a valve, no copression, no difference in engine note even if plug is firing and coil is ok.

[JTT3]

Warwick I’m leaning toward your post.
He has fire to the spark plug wire
He has moved coils & plugs to different cylinders
No change in engine on number 1 when grounded
New wiring
E timer

Questions/statements
No compression test done? That may answer every thing with number 1 with the exception it’s not firing through the plug, baffling
Did you replace the valves
Are they seated properly
Have you switched #1 spark plug wire with another
(Sometimes the solder separates at the ends)
More invasive- have you removed valve cover and inspected movement of valves especially #1 cycling the engine

Just some thoughts but to save you misery do a compression test first. Air, fuel, compression, spark. Boom

[Scott_Conger]

Ran fine Friday
Ran fine Saturday
washed the car
#1 and #4 plugs won't fire

color me stupid, but that doesn't lead me to suspect a failed valve

the complaint starts with #1 not firing, then a description of a ton of work, then a description of the car running fine, then wash the car, then two plugs won't fire. Honestly, no one can offer meaningful advice in light of the mish-mash of information given, beyond the fact that combining coils, plugs, coilbox, water and stirring well often results in the described problem.

post a timeline of faults vs repairs vs results and you'll have a correct answer quite quickly

[JTT3]

Hear what you’re saying Scott but his latest post didn’t mention #4, though the omission doesn’t mean it’s solved for 4 though I assumed (yep I get the assumption analogy) it was resolved. I think he stated #1 fired through the spark plug wire but not through the plug in the cylinder despite changing plugs. That’s interesting. So you may be correct minus my assumptions.

[Scott_Conger]

John, I failed to digest the second post fully...thank you for pointing it out to me...but regardless, the complaint on #1 has gone from:

There is spark at the plug and can get an arc when shorting it to the cylinder head with a screwdriver...

to:

Thinking valve issue also but plugs were also not firing out of cylinder

one or the other is true, or both are true at different times and that change has not been made too obvious...so from my perspective, until and unless a timeline of faults, conditions, remediation, and results is given, in the exact order that they occurred, the fact remains (as best as I can decipher) it is still a T which ran fine until it got wet. If simply guessing and poking at it really is still a fun thing, then yes, a peek inside to see if valves are moving, or a compression test is done, then more information will be gained. Still, I will bet that both are just fine. Things rarely break just sitting overnight. If they did with regularity, then there is not a T in the world which could be coaxed into running after sitting for 50 years, and yet it is done all the time.

the nature of the forum is for 20 guys to offer 20 guesses, then a bunch of work gets done on 20 different things; the problem changes a little or a lot, or not at all, and everyone declares in unison "I was right!". It's fun to watch, but not much really gets learned, and things will invariably repeat 7 days later, with a different poor soul and a different car.

this will get solved sooner or later, or it will get sold as so many of them seem to be...as evidenced by the great number of "I just bought this great car, but it won't run smoothly". Usually when the previous owner says it will sound better the longer you run it, he means it will sound better to HIM the further away you get.

[TXGOAT2]

You might try parking the car out in the sunshine with the hood open and the coil box lid off.

[John kuehn]

If you have another good timer install it and see what happens.

[Tim Rogers]

Richard- the timer below works flawlessly and will never give you trouble...

[JTT3]

The puzzling part of this is that Richard said he was getting spark through #1 spark plug wire but not through to the spark plug consistently despite swapping plugs/coils out/around. Scott I think has it right by having Richard post where he is currently in problem solving and what is corrected and what needs correcting. While it is admirable that we are all ready to help, including me, we’re just spinning the web without anything to catch until he gives us a list of what currently is the issue. I know I’ve contributed to spinning the web in an effort to help so I’ll stop until we hear from Richard (OP).
Best John

[Norman Kling]

Unless the plug is out of the hole and grounded at the base, with the lead on the top, he will not be able to tell whether or not he is getting spark THROUGH the plug. Even if he does get spark under that condition, that does not mean it is strong enough to spark under compression. It would still be dependent on whether he gets fuel mixture into that cylinder and the compression is good. It would also depend on the condition of the spark plug, coil, and timer.
Norm

[RVA23T]

It is crazy that with all of today's tools we have to communicate it is hard to get across what one is saying and online it is quite the balancing act between too much and too little information.

The oddity or challenge was having spark at the terminal/top of the plug (#1 & #4) without spark jumping the gap or firing while resting on the cylinder head nor while installed and the terminal shorted to the head and it did not change with swapping plugs, wires and coils (the standard answers) and while installing and adjusting the I-timer, there was no issue with all plugs firing in and out of cylinders. #4 was resolved after drying off with compressed air around the coil box terminals at the firewall but #1 would not spark at the gap in spite of coil function proven at the top/terminal input of 3 different plugs used for verification and this is what I could not work through and found puzzling and requesting help on.

I parked her in the garage Sunday evening with the goal to diagnose more on Friday.

For just the fun of it I started her today and I am HAPPY to report that the #1 plug is now working and firing the #1 cylinder as it should. I am thinking water went somewhere that increased the resistance of the coil output that would not allow the spark to jump the gap and after drying out for 3 days it went away.

I intend to look at the coil box on Friday to see if anything stands out and if I find anything to report back on.

Thanks

[Scott_Conger]

kinda' thought this would be the upshot, and Pat advised to do what everyone MUST do in this case

everything revolved around getting wet and what almost certainly happened is you created, or had, a carbon track in your coil box due to moisture. This is why folks go to the thermo-plastic rebuild kits for coilboxes and those sorts of troubles become a thing of the past. The carbon is too resistive when the plug is in open air, but when the plug is put under compression, the resistance to ground exceeds that of the carbon track and that's where the spark goes. Now you know that you have a new job ahead of you

good for you

[TXGOAT2]

Sounds like you had wet ignition. It can be difficult to get things really dry, especially if you are in a humid environment. Old, decayed, or compromised insulation,especially in the presence of humidity, salt air, road salt residue, etc, can make an ignition system very prone to leak off high voltage.

[Norman Kling]

If your coil box is still behind the firewall you should remove the coil box so that you can examine it on both inside and outside. This will be a bit of a chore, however that is the best way to do so. Then you could replace the wood with the replacement plastic material and your troubles will be over.
Also sometimes the contact between the copper springs and the coils is loose, So be sure it makes good contact and that the contact bolts are clean and soldered to the spring contacts. And also the cover should hold the coils in place securely.
Norm

[TRDxB2]

Trying to follow all this ..... and isolate the problem
Are these true.
Any plug wired to #1 wire sitting of the top of the engine shows spark.
Any plug screwed into #1 plug hole using #1 wire does not fire, and there is continuity with the spark plug base and the engine head.

[RVA23T]

So be sure it makes good contact and that the contact bolts are clean and soldered to the spring contacts. And also the cover should hold the coils in place securely.
Norm

I know the contactor springs are not soldered to the bolts. When installing the insulating washers I removed a bolt all the way so I know they are not. I bet there is a good point of added resistance and a great spot for moisture to park for a day or two.
Gonna solder them together.

Thanks

[Mark Gregush]

Did you turn the gas on?
Do you have a different stock type timer you can try?

[RVA23T]

Trying to follow all this ..... and isolate the problem
Are these true.
Any plug wired to #1 wire sitting of the top of the engine shows spark.
Any plug screwed into #1 plug hole using #1 wire does not fire, and there is continuity with the spark plug base and the engine head.

Any plug wired to #1 would NOT spark sitting on the top of the engine and any plug would NOT fire installed, but could do my family's secret test with a screwdriver and get a spark to jump from the top of any plug weither in or out of the cylinder while attached to the #1 plug wire at the top of any plug.

I know the block has continuity based on earlier that day installing and setting up my timer and all 4 plugs fired while on top of the block.

[RVA23T]

Did you turn the gas on?
Do you have a different stock type timer you can try?

Yes on the fuel on.
I don't think timer now based on the deductive reasoning that there is a considerable amount of resistance in my #1 coil output to the plug because I allowed the firewall to get wet and after sitting 2 days in the garage with the coil box lid off,it is not missing.

[KWTownsend]

I still think you have a carbon track issue.
Swap out the coil box with a known good coil box.

: ^ )

Keith

[TRDxB2]

Trying to follow all this ..... and isolate the problem
Are these true.
Any plug wired to #1 wire sitting of the top of the engine shows spark.
Any plug screwed into #1 plug hole using #1 wire does not fire, and there is continuity with the spark plug base and the engine head.

Any plug wired to #1 would NOT spark sitting on the top of the engine and any plug would NOT fire installed, but could do my family's secret test with a screwdriver and get a spark to jump from the top of any plug weither in or out of the cylinder while attached to the #1 plug wire at the top of any plug.

I know the block has continuity based on earlier that day installing and setting up my timer and all 4 plugs fired while on top of the block.

With a good plug (one that has fired in all the other cylinders) in #1 and being able to jump a spark from its top to the head and able to jump with screw driver from top to head when when screwed in BUT will not fire on its own , questions if there is an issue with the plugs base having continuity to the head in order to cause a spark. While you test head continuity you still need to test continuity from the spark plug base to the head when its screwed in. I'd test that. Is there any sealant being used around the plugs threads?

[RVA23T]

I might have found the issue with the coil box. It is contaminated with a Phillips head screw!

Bad Phillips Bad

[RVA23T]

Looks like the plywood in the box got more wet than I thought while washing thins off last weekend. I have zapped the 4 hole backer board and it let off a good bit of steam.
I have soldered the tabs to the bolts. Did not find any carbon tracking so it would have to have been the water retinsion in the old plywood causing the extra resistance.

It's going back together for the weekend and I'll be order the recommended plastic replacement for the wood.

Case closed & thanks for all the input.

[Professor Fate]

I installed the plastic fake wood panels in my '26 coil box. Went together easily and will eliminate problems going forward.

[Jerry VanOoteghem]

Looks like the plywood in the box got more wet than I thought while washing thins off last weekend. I have zapped the 4 hole backer board and it let off a good bit of steam.
I have soldered the tabs to the bolts. Did not find any carbon tracking so it would have to have been the water retinsion in the old plywood causing the extra resistance.

It's going back together for the weekend and I'll be order the recommended plastic replacement for the wood.

Case closed & thanks for all the input.

You won't typically see the carbon tracking on the surface of the plywood. I tends to occur in the glue seams between the plies, where it can't be seen. Best to replace the plywood with the plastic rebuild kit.

[TXGOAT2]

Always suspect water conmtamination of the ignition system when a vehicle exhibits problems after washing or other exposure to water. This is important even if the problems do not show up immediatley after the exposure. Water can affect Model Ts with stock ignition in several ways. In the case of cars with distributor type ignition, it is not uncommon for a small amount of water or water vapor to get into the distributor. This may not cause any issues right away, but moisture may condense on the inside of the distributor cap while driving the car or after it has sat overnight and cause serious problems. Stock T systems can allow water to get into the coil box. It may cause trouble right away, or it may cause trouble down the road. Water can get into the engine compartment on a T from road splash or leaking through the hood hinge. It can get in via the hood louvers or leak in around the rear of the hood and run down the firewall. Radiator fins can collect and hold large amounts of water. Starting the car will allow the fan to pick up this water and spray it all over the engine and firewall. High humidity or other wet condition, including running a wet engine, can allow enough water vapor to collect in the coil box to cause problems after the car cools down or after the car sits overnight. An ignition system that is Kept clean and has all insulation in good condition will minimize problems.