Ignition Issues

[jagiven]

I have been fighting my T all year so far. It is running better, but not great. I cannot set the timing to a low idle, with the throttle closed down, I need to keep the timing set past 9, or it will stall. While driving at full throttle, I can feel a little lurching maybe every 20 or so seconds, which makes me think carb. I always start on battery and run on magneto. While on battery, the car has a lot of shake, flip over to magneto, and she calms down.

What have I done so far;
• Last fall I had the points replaced and set, by a well-known individual
• Pulled the carb (26 NH) and cleaned it.
• Rebuilt the linkage for the timing rod.
- The pin was worn and the small leaver arm was loose, and I had no adjustment at the steering wheel.
• Gapped the spark plugs to 0.030 (Champion X). Visually they look good, cleaned them.
• Replaced the Anderson timer with that had 15K+ miles on it with a new Anderson.
• Checked the timing, set to 0.5” past TDC.
• Rebuilt the coil box (New plastic box kit), found the old wood box was arcing when I was setting the timing.
Next thoughts are to pull the carb again and re-clean, just incase there is something in the jet, try a different spark plug gap, maybe down to 0.025”. Considering swapping out spark plugs to a set of cheap Autolites. Pull the magneto post and check for debris on the tip.

Any suggestions

Usually by this point of the summer I might have 1K miles on the car, so far maybe 50 miles ☹, still on the first tank of fuel.

[Scott_Conger]

If you have set timing at 0.5" past dead center this is your problem. You don't really mean the piston is down 1/2" when spark occurs, do you? Having to run so much advance just at idle, tells me I may be right in how I read your post...

[Mark Gregush]

For starting on battery the timing only needs to be set so the piston is just over top dead center on it's way down. Once the car starts the lever needs to be pulled down to where it runs more smooth by sound not by a number of clicks and adjusted as you drive. Same with the spray needle, adjust by engine sound.
Where are you setting your spray needle adjustment?
Have you checked for vacuum leaks around the carb and manifold?
T's are pretty forgiving, I know guys that have been driving theirs for years and still start the car pull the spark lever down and really don't touch it much after that.
RE the spray needle, if you try to run too lean it will idle poor and can over heat esp if the timing is not advanced enough.
There are no set of hard fast rules, just general approx. suggestions on where to set things.

[Ruxstel24]

Sounds like possibly a couple issues.
Start with the timing, "9 notches down to start",
doubtful you can advance far enough that way.
Then tinker with the carb and report back.

[Mark Gregush]

Assuming you are timing for startup with spark lever all the way up/retarded. ? If you are not sure how to time it, Google "mtfca; timing".
Let me be a little more clear on this: "There are no set of hard fast rules, just general approx. suggestions on where to set things." I am talking about where to set the spark lever and spray needle AFTER starting.

[Steve Jelf]

Start on BAT with the lever all the way up (fully retarded). Set timing like this:
http://dauntlessgeezer.com/DG97.html

[jagiven]

Steve, my technique was definitely different than yours. I just followed what the Anderson Timer paperwork said. It stated to set the spark when the cylinder was past TDC between 1/2" to 3/4". I thought it seemed like a long distance, but I will double check the paperwork, and readjust closer to 15o

I start the T on battery, with the spark fully retarded, then advance it once going.

I think I have only set the timing when I first got my T.

[DanTreace]

Need to re-read those instructions, the timer is set for initial timing of #1 cyl. when that piston is just PASS Top Dead Center. "...only after the piston is just started on the way back down after it has reached the top of its stroke" The best if you can hit it is 15 degrees past, tools can be used to do it, TRW has one, or the hint of the pin in the crank pulley, horizontal (9 - 3 o clock) is TDC, 15 degrees past is about 9:30-3:30 on the hands of a clock.


Those measures in the Tip Top Timer inst. for the Anderson are just comments on where the timing may occur at full speed, but that is advance, BEFORE the piston reaches TDC.

[George N Lake Ozark]

I'd had been having similar issues like you state. After consulting with two friends with long experience with these T's They advised me on how they set their timing and it made a world of difference . When you bring your spark lever down to half way (14 notches on my quadrant) the bracket on the timer should be at the 12 o'clock position. I gave it a try. Adjusted this way as close as possible and my T loves it.(Stoked) Maybe give it try , then adjust carb as ness.

[Scott_Conger]

George

if it works for you then it works for you...

Given the differences between timer manufacturers' small differences in location of contactors, it's not advice I would give, but like I said if it works for you, it works

One of the biggest mistakes a person can make is to use the "universal" timing tool shown in Ford trade journals, and marketed by suppliers, and then try to use it on ANY timer that is not FORD. It is only a certainty to be correct with FORD timers. You simply cannot count on the contacts to be exactly the same between manufacturers, which is why I view your method to be very hazardous to stem-winders (big time) and somewhat less hazardous to starter shafts.

I believe it's plenty easy to measure piston location, or view the crank pin (which is foolproof) for 15 degrees ATDC, as I value the structural integrity of my wrist and forearm...and anectdotes like your friends espoused is also why I WILL NOT hand crank someone else's car...

please understand this is no criticism of your method...it works...but is a little dicey for someone new at this to try with a worn or unknown timer. This is one of those uti caute (use with caution) moments, I think.

[George N Lake Ozark]

No worries Scott. You are right with all the diff. timers out there. Not to mention all the kinds of wear along the system. I think most of these ways are all "In the ballpark" adjustments.

[jagiven]

Timed using Steve's technique. Runs well on battery. Stalls now on mag at about 5-6 notches. I did not get to road test it, due to rain. Also found it wants the fuel air mix at 1 turn. She has always want 1 1/2 turns during the summer. 1 turn during cool weather.

I did have to bend the timing rod to shorten it. I should check the timing again, as I had to adjust the rod after I reinstalled it, due to an interference.

[Steve Jelf]

I think a stall on MAG has to do with something other than how the timing is set. Switching over from BAT to MAG a car should run just as well or better. Mag post fuzz? Loose wire? Intermittent switch?

When you adjust the timer rod by bending, be sure it doesn't touch the #3 timer terminal.

[Mark Gregush]

Reading the postings I get the impression you are fixating on number of clicks rather then engine sound. (?) If you are using the chart, it was published in the era of brass quadrants. They have less/larger grooves then the later pressed steel. I would suggest paying less attention to number of clicks and more to how the engine sounds. Other issues at idle are for example; float level and plugged passages. I have yet to work with an NH that didn't need a bit higher RPM at idle so maybe you are trying to idle it down too slow.

[jagiven]

It is running better, maybe not 100% yet.

Adjusted the timing closer to 15 degrees past TDC. On battery it will accept a low slow idle. On Mag I was only able to get it to a slow idle once the engine was nice and warm.

I found;
- Coil #4 did not have as strong of a spark as the rest, so I swapped it out.
- Coil #3 while hand cranking, I could not stop and hold a long spark. I plan to swap coils to see what happens. The momentary static spark looked strong.

Potential Issue;
- Coils 2 and 4 have a strange phenomenon. While doing a static spark test with the plugs removed and a screw driver grounding the spark. If I move the screw driver to the next plug over, I can see a very small arc if I ground out that plug wire even though the spark is set on a different plug. I do not see this with coil 1, and cannot get coil #3 to hold a continuous spark, so I was not able to test it.

Overall running much better, I put it through a wide range of driving conditions on a 20 mile ride. Top speed is not as great, maybe 35 mph, in the past I have been able to get to 50 mph (I do not normally drive that fast). Very smooth at the lower speeds (25 mph, drove about 10 miles at this speed). Historically this car likes 1.5 turns on the carb, but it wants to run at 1 turn right now, so that might explain the lower top speed.

I was a bit nervous to try low idle in traffic at stop lights/signs in fear of stalling, so more testing is required. I only felt a little bit of learching at higher speed, so I will swap out coil #3. I might swap them around and then try a spare coil. I now feel as I can drive this car reliably.