I've had my '26 T for just over a month and have been successful in getting it running and made a couple of small road trips. However the engine "smoothness" seems to vary pretty frequently while its running.

- I have figured out the right position for the spark and throttle to get it started and to run it. Sometimes it seems like i can move the spark advance lever quire a bit with no change.

- Sometimes it just runs smooth and sometimes it runs rough with no intervention on my part.

- It will run on battery and on the magnetos, but there is a definite difference when i switch between them. When i switch to the mags the rpms seem to drop a little but it does run, once in a while it just stops when on the mags. I don't understand why it would change when switching between them

- It has Autolight plugs that i have had out and cleaned, they weren't too bad looking.

- The wires look to be in reasonable shape

Where should i start looking to see if it's timing or wires or whatever?

Is there a step by step how to guide to check the timer?

I'd start with looking to make sure the lever moves the timer. Could have fallen off. On mag you have a couple "sweet spots" on the lever due to the peak pulses in the electricity. As for quitting on mag - look for the usual, loose connections, etc. before getting too excited. Check your coils too - a double spark or ill-timed release will affect the way it runs on mag. I'm in SE Mass if you can't find a local guy with a good coil tester (not the buzz box).

Couple of questions Ken:
Does your "T" still have the 6volt system or has it been converted to 12 volts?
Do you still have the lid on the coil box?
If you rotate the engine slowly on battery do all 4 coils Buzz?
Has the Car sat for a long time and if so has the fuel tank been cleaned?
Definitely check all electrical connections first!

Another good check you can do is to set the engine running at a slightly fast idle.
Remove the coil box lid.
press lightly on the lower points of coils 2 and 3. This will stop cylinders 2 and 3 firing. The engine should run evenly on cyls 1 and 2.
Then release 2 and 3 and stop 1 and 4, so the engine runs on cylinders 2 and 3.
This will show you if there is any problem with a cylinder or coil. You can swap coils around if one cylinder has a fault - to see if it's the coil or the cylinder.
Don't touch the HT leads while doing this - the rest is safe.

It's normal for there to be a difference in RPM when swapping from battery to magneto. I suppose it could go either way depending on where the spark was set when you swapped over, but the dramatic difference will be noticed at highway speed. The magneto should give noticeably better performance at highway speed than you will ever achieve with 6 volts. If you are running on 12 volts, you probably won't see any difference. It is also normal for there to be significant movement of the lever with no change in engine performance when running on magneto. On battery, the adjustment is infinitely variable between the two extremes of fully retarded and fully advanced. On mag, there are only 3-4 "Nodes". You will pull it and no change. Pull it and no change. Then suddenly a change, but then it will do the same thing again until the next change. If it stops on mag while idling, you may have a weak mag. You can search on how to test it. You will need an analog volt meter (Not a digital) and an 1156 light bulb with either wires soldered to its contacts or a cheap socket with a pigtail. You should also check your timer. Not sure which type you have, but if it's a roller or brush type, the surface of the timer should be nice and smooth. No grooves or bumps. Flappers are a little more forgiving, but can certainly wear too. Lastly, it would probably be a good idea to have your coils professionally rebuilt. Running better on battery than on magneto is a classic sign of a coil that is not up to snuff.

What Hal said is correct. When you run on battery, the timing varies with the position of the spark lever, so it will speed up with each notch you move the lever down from full retard. Once you reach a certain point, usually about 3/4 down the engine will begin to lope. This point will vary according to engine speed. You can pull it farther down when the engine is running faster. When you pull a hill or shift from low to high the engine will slow down and you will need to slightly retard the spark.

When you run on magneto, the spark will advance with the speed of the engine because the voltage output of the magneto increases with engine speed. This advance is also dependent on the position of the timer in relation to the peak of the wave generated by the magneto. The amperage will reach the point where the points open and the spark jumps. This point is sooner with the higher voltage output of the magneto with speed of the engine. What Hal and I refer to as "nodes" are the points where the timer moves to the next position of the magnets in relation to the coils inside the magneto.

In short, when you find a "node" try to move the spark lever to approximate center of the node for best performance as the engine speeds change.

Another potential problem could be the setting of the points and tension of the spring on the individual coils. The points should be set .030". The tension should be should be set to spark at 1.3 to 1.5 amps.

You also need a clean timer.

As you drive the car you will find two adjustments which will smooth out the running of the engine. One is the fuel mixture which when the engine is warm should be turned clockwise till it begins to slow down then counter clockwise till it begins to lope. The best setting is about half way between these two points

Assuming that the spark comes just after top dead center with the spark lever all the way up, the best place to run is about 3/4 down after the engine is started. Then as you drive you will find the place where the car runs smoothest and has most power for the driving conditions and speed of the engine.
Norm

Oh boy, this is like trying to drink out of a fire hose for me...

- This is a 6 volt negative ground system.

- The car did sit for 2 years, but the fuel system was drained. I replaced some rotted hoses, added a fuel filter and a shutoff valve, and put in fresh gas. So i don't think it is fuel related

- I believe all of the coils are buzzing, but to make sure i will pull the cover off of the coil box and make sure they are all working.

- There is a bit of play in the spark advance lever on the column. When i have it totally rotated clockwise until it stops i can then move the lever CCW about 15 degrees or so before it moves the lever attached to the timer. I think the hole at the end of the rod in the column is widened out a bit.

- I have not done anything to the timer at all because i haven't a clue where to start. It would probably make sense to make sure it is at least clean. Are there any instructions or video's on how to do this?

Ken fuel filters don't work well on gravity fed systems too much restriction.
this part is probably worn and is replaceable on the end of your spark control rod.
https://www.modeltford.com/item/3530.aspx
The spark control rod is also replaceable if needed but that is rarely the case YMMV.

Timer cleaning is pretty straight forward. Loosen up the bolt that holds the clamp in place and pull it off. If it is a New Day, it should be clean and smooth and dry inside. No oil. If it is a Ford roller type, get a rag and maybe some mild solvent (mineral spirits maybe) and wipe it out. The little 'track' around the edge where the roller rolls should be smooth with no dips or bumps. The roller should roll smoothly. Oil it or grease it and put it back together. If it is an Anderson (Flapper type), just clean it and check the flapper and contacts for wear. You'll get different opinions on how to lube them. The New Day should not be lubed at all. The others need to be. Some do the light oiling bit that Ford called for. I put a handful of grease in mine.

Ideally, there would be no slop in the timer linkage. In reality, there's probably a lot more of them out there with slop than most on here will ever admit. Take as much slop out as you can and deal with the rest. I adjust mine so that with it fully retarded (Lever up), it fires JUST after TDC. Yeah, I know the book says 15 degrees after, but as long as it fires AFTER, you will minimize your chance of kickback. The extra bit you gain by not going the full 15 after goes to the other end in the form of more advance.

I agree, ditch the filter.

Cleaning the timer is supremely uncomplicated. Remove the cotter pin from the control rod, loosen the bolt holding the clamp, and pull off the timer cover. Clean it. Put it back. Be sure it's seated properly in place before you tighten the clamp. If it's a roller type or a flapper type, apply new grease after cleaning. If it's a New Day or other brush type, leave it dry. Here's how to set the ignition timing: http://dauntlessgeezer.com/DG97.html

In your profile comment you question the year of your T. Yes, 1926. The lack of a headlight bar puts it early in the model year, perhaps in the fall of 1925. The engine serial number can pin down that detail.

Thanks for the help here. I'll try to do some wrenching this weekend to see what i've got going on. And i will remove the filter too.

I was able to get it registered and plated today, so i am making progress.

There should be a sediment bulb where the fuel line comes out of the tank. On the 26 that would be on the firewall right above the carburetor. See picture attached. That sediment bulb originally had a very fine screen inside it. Any water or heavy particles in the gas should settle to the bottom of the bulb and from time to time you can drain out some gasoline by opening the petcock at the bottom of the bulb. That will allow the water or particles to drain out. Any modern filter will restrict your line. With a modern filter, you might get the engine to start, but only run until the carburetor bowl is empty then the engine will stop and you will have to wait a while for the slow trickle of gas through the filter to run into the carburetor. So it's best to delete the modern filter. If you have a Fordor sedan, with the gas tank under the front seat, your sediment bulb will be in the middle of the underside of the car under the gas tank. All other models of 26 have the tank in the cowl and the sediment bulb above the carburetor.
Norm

I forgot to attach the picture

Norman, I have a 26 Tudor and run a modern metal filter. Plenty of flow and no issues.