MTFCA Forum

Hey everyone, sorry for the long post, but here goes -

I’ve owned a Model T (24 touring) now for almost 20 years. Some old timers here may or may not remember me from the old forum. Anyway, about 10 years or so ago my life took a different turn and I put the T into storage. I still maintained it, but really didn’t drive it anymore or participate in T activities. The last week or so I’ve decided to get back in.

Now for the bad part.

Shortly before I put the car away, I put in a True-Fire ignition that ran flawlessly, after all those years. I ran it on 12 volts. Took it out last week, and it still ran flawlessly. However, reading all the posts about the charm of running a T on coils and a timer, I decided to convert back to that system. I put in my set of coils, and a New Day timer that I knew to work from years back. The car ran great for about a minute, and then started missing like crazy. I shut it down right away. So, I figured maybe there was a crack in the timer or something like that, so I then put in an Anderson timer that I also knew to work from before the true fire conversion. This time it started, but ran rough right from the beginning. I shut it down again, and I figured maybe I had a bad coil. So, I figured I’d put the true-fire back in, and look into getting some new coils, and continue to use the true-fire until then. But now, it won’t start on the True Fire either.

I made sure all my wiring was clean - I replaced all the crimp connections on the timer posts, so I know they are ok. The only thing I can think of is a short somewhere, but there was no short before I did the conversion.

I’m kind of rusty on this stuff, a little frustrated, and I’m stumped. Any ideas on what’s going on?

(Thanks for bearing with me through all that)

Does it run the same on battery and on mag? If only mag, you might need to charge the magneto. It could also be a problem with the coils, however, they ran on tru fire. It could also be a problem with your timing. Each timer is a little different on where to set the rod for best timing. I would suggest that you turn the ignition to batt and then ground one by one the top connection on the coil box. the coil to that wire should buzz when it is grounded. If it does buzz then something is wrong with the timer or the wire between the coil box and the timer. Be sure the wires are connected so that the correct segmemt of the timer is connected to each coil in firing order and that it makes contact in the timer just after the piston passed top dead center on the compression stroke. The timer can be adjusted by bending the rod linking the steering column and the timer.
Norm

The magneto is currently set up to charge a separate 6 volt battery for use with the starter only (with a kit I got several years ago from Fun Projects), so at present I can’t run ignition off of it. It’s a completely different system from the ignition. The mag is strong because I put in fresh magnets when I rebuilt the engine back then.

When the car was running well for that brief time at first, I shorted out each cylinder one by one to make sure they were all firing ok, and each one showed a noticeable difference.

One thing that did happen that I forgot to mention was that I was getting so preoccupied with what was going on that I forgot to turn the ignition key off when I took the Anderson timer off, and I got quite a backfire when I accidentally touched the motor with the timer. That really woke me up!

What i understand from your story is that the car ran fine on the True fire, the car ran fine too on the first regular timer and coils you installed for the first ten minutes or so, and when you changed out the timer for another known good timer kept missing some beats.
Sounds to me like a fuel problem ?
I'd check the coils, see if swapping places changes the missing cylinder, if nothing changes there are a few options, spray some brake cleaner or wd40 around the intake manifold, it might warp when heating up and develop a leak, if not, next step is clean carb and potato screen and check the tank for crud and/or rust blocking the outlet, fuel line or carb orifices
How old is the gas you are running on ?
Oh and how long did you leave the ignition key on battery when working on the car, if left on for long periods the coils not being able to discharge one may have been damaged internally.
Good luck on your quest !

Kaiser wrote: ↑

Thu Sep 21, 2023 5:16 am

What i understand from your story is that the car ran fine on the True fire, the car ran fine too on the first regular timer and coils you installed for the first ten minutes or so, and when you changed out the timer for another known good timer kept missing some beats.
Sounds to me like a fuel problem ?
I'd check the coils, see if swapping places changes the missing cylinder, if nothing changes there are a few options, spray some brake cleaner or wd40 around the intake manifold, it might warp when heating up and develop a leak, if not, next step is clean carb and potato screen and check the tank for crud and/or rust blocking the outlet, fuel line or carb orifices
How old is the gas you are running on ?
Oh and how long did you leave the ignition key on battery when working on the car, if left on for long periods the coils not being able to discharge one may have been damaged internally.
Good luck on your quest !

Agree with the above, and also wondering how well charged your battery is.

Batteries die in storage, and fuel decomposes into varnish. Be sure one or both of these are not the source of your problems.
Be sure the fuel screen is clean and that you have clean, fresh fuel in the tank. It's possible you have a sticking valve issue. Adding Marvel Mystery Oil to the fuel as directed may help valve action. Model Ts don't like thick oil or dirty oil. Be sure the oil is clean and free of moisture. 10W30 is good for general service.
Gently seating the carburetor adjustment needle, then adjusting it as needed may improve performance.
Coil points can corrode over time and need cleaning, and coil capacitors can go bad in storage.
Many coils are in need of proper adjustment.
Cleaning, inspecting, and adjusting spark plugs may be beneficial.
If your coil box has wooden insulation, it may need replacing. It can look good and be bad. Coil box contacts need to be clean and in good condition.

Since it quit running well when he returned to the TruFire it can't be the mag, as TF doesn't use the mag at all. He's got some other problem somewhere, maybe even in the switch. Yes, bad gas could be the culprit, and the carb, I didn't read all the previous posts after he said he returned to the TF so maybe that's been covered. Got a gremlin in there somewhere

Thanks for all the replies and great suggestions.

I got it to run on the True-Fire this morning. It’s amazing how much better old eyes and brains are with a good night’s sleep

Maybe the battery has enough current to run the True-fire, but not enough to run trembler coils at 12v? I see it as being a spark issue of some kind. When I put the battery in my Gravely tractor, it’s got enough cranking amps to turn it right over.

I’d really like to switch back to using trembler coils - there’s nothing like that Ford tick-tick-tick

The thing that confuses me is that it ran fine on coils and a New Day timer for about 2 minutes, then suddenly started missing. Maybe Norm was right, the timing was off due to the position of the spark rod, but it took a few minutes of fuel consumption to start flooding the cylinders?

Did you put in new fuel and clean the fuel screen? Rebuild the carb? After 20 years the gaskets and seals might be dried out and after running for a few times, the filter might be clogged now and not allowing any fuel to get through. Make sure all the carb adjustments are correct. Especially the float adjustment. Sometimes after a long time, insects, such as wasps get in there, build nests and cause problems. Lubricate the timer roller? Is the one of the timer wires grounding out against the rod or block? Could the vibration from running a few times have caused a loose wire? Do you have access to ethanol free gas (www.pure-gas.org)? Jim Patrick

Bob Sacchi wrote: ↑

Thu Sep 21, 2023 10:02 am

The thing that confuses me is that it ran fine on coils and a New Day timer for about 2 minutes, then suddenly started missing...

... as your battery was going dead.

Just for the heck of it...

You may want to check the screen in the sediment bowl 'potato'?

When I was first into T's like in the 70's...I had a barn find long storage car that surprisingly ran decent...for a while.

Start it up, go for a mile...spitter sputter cough wheeze. Wait 5 minutes would start right up again...for another mile or two...

Went through the ignition - - - baffled.

Tried using fuel treatment and fresh gas - - - baffled.

Somehow...as a last resort dropped the 'potato' and took it apart, more so to see as a newbie if the on off lever may be off, as in bent and restricting fuel flow.

On disassembly...the screen had...a filter! Well sort of...it was basically a Brillo pad type accumulation of 'stuff' that looked like a rear axle felt that covered the entire screen! Cleaned it off, put it all back together, never another problem forward with that car.

My guess was that fuel would tickle through, not flow through. Cough and sputter and die, the 5 minute wait would allow the bowl to fill enough to restart and go a few miles before a fail...

May be worth checking, simple enough.....

All of those things were addressed (fresh fuel, sediment bulb, new oil, lubrication of all points, new antifreeze, tire pressures, transmission lint screen, etc) when I got it out of storage. It ran fine on True-fire for several days, and after the timer/coils experiment it still runs great on the True-Fire.

The issue is what happened when I tried to switch it back to stock coils and timer(s). I think Jerry V might be on to something with the battery, but I’m assuming (?) that’s because trembler coils are much more “current-hungry” than the solid state workings of a true fire….as I said, the battery was put into a tractor and had ample amps (!) to crank that vehicle.

BTW the car has a Becker 12v (AC Delco?) timing gear driven alternator. I have no reason to think it wasn’t charging the battery the several times I drove the car over the last week.

Seems you ruled out all other possibilities and the coils are the culprits, although coils tend to like a little more than 12V, the car should run decent on battery.
Check all contacts, check the coil box for carbon trails (there was a recent post on that, https://www.mtfca.com/phpBB3/viewtopic. ... 50#p298789 ) and find someone who can check and adjust the coils either on a HCCT or ECCT

Check the alternator output under operating conditions and be sure you have a good battery of ample capacity that is fully charged, from whatever source. Batteries that are known to be good aren't, often as not. Send your coils in for a rebuild. If your coil box does not have modern, composite terminal boards, obtain the parts and install them. The stock ignition system should start and run on 6 or 12 volts, and it will run best on magneto.
A fresh, high quality, full size battery is a good investment. Optima type batteries also give good results. Plug wires can look good and be bad.
The timer must work as it should for consistently good performance.

If the car was sitting for 10 years, I would expect fuel system issues unless it was started on a more-or-less regular basis. If it was started regularly and gassed up with fresh fuel regularly then you are probably OK there. Why was the car converted to 12V and distributor?