MTFCA Forum

After fresh oil loosened it up enough I could only get 3 volts AC, after reading past posts I gathered 3 hot batteries and my good 00 wire jumper cables, couldn't find anything other than north, and a little less than north I just picked a spot I could find again , marked it on flywheel, after 2 days still had 7 volts AC, then thinking about coil operation I decided to look at it as a changing polarity dc pulse on my snap on vantage meter, the dc pulses are 9volts open circuit, and with headlight bulb load I am getting 6.2 volts hand cranking--- should I expect more or is that good enough.
I made a quick spark gap and could get some sparking, #1strong, #3 weak if at all, even changing coils #3 weak,
I decided to try voltage drop testing, 2 h7 headlight bulbs are 7 amps, I use them for testing on modern wiring, got .34 on mag, .32 on battery on the power side to the coil contacts, on the ground side .56 on #1, .79 on #3. --- loosing over a volt, ---- so I am soldering or cleaning every connection.
The engine timer is a "twin timer" , nothing about it shows in searches, is it going to be trouble?
There's this tin with rubber sleeves between the coil box and firewall--- I don't see parts to replace the rubber, is it something I should leave out?
How much free air spark gap will I need to have a viable hand crank start on magneto?

Throw the "tin with rubber sleeves" in the garbage. Has no place on a Model T.

Edit: Sorry if that sounded angry or abrupt... As Scott suggests below, leave it out for now. Like your accessory timer, it's a variable that you don't need right now. Get everything "back to basics", with a known good set of coils and go from there.

Kurt

it sounds like you are doing all of the right things. The rubber/tin boot is an accessory and as Jerry advised leave it out. If after everything is running right and you just love it...put it back in and see how things go.

Get your coils tested/rebuilt...no point struggling with something that won't ignite the fuel
Change the timer to a conventional modern timer - brand is your choice...once car is operational, like the weather boot on the coil box, if you like the timer that came with the car, then try it out. If it's a dog, then put the new timer back on.
adjust the timer correctly for your car (do NOT plan to use the timer gauge sold by vendors and necessarily expect things to be correct - they are for ORIGINAL FORD timers only, though the vendors won't share that with you)
install good solid core spark plug wires (no modern carbon-core ones). Resolder the connections on the wires if they are cold blobs...should be smoothly flowed bright joints but often are not. With T parts, you are your own quality control inspector.

I question whether you are truly getting 6+ V hand cranking...if true, that is spectacular! Hand cranking usually results in only 2-3V and that's perfectly adequate. Coils are current operated (1.3A nominal for conventional adjustment) so they will fire at pretty much any voltage over 2V. Lots of theory that you will eventually understand about coils and T ignition, but you don't need theory now...you need good parts.

Good luck and keep folks up to date on your progress...lots of help available here

Definitely a little over 6v, the trace on the meter shows it, and the 12v bulbs make 6volt brightness .
I'm going to put the coil box back in tonight.
Is ther a piston position specification for timing?
I already fixed the wobbling, loose lever pinned with bent nail--(shrunk lever with heat and drilled for larger pin made out of larger nail)--- I already know the tool and this timer are not compatible, was thinking of putting degree markers on flywheel

If the rubber insulators are old, they have likely lost a portion of their insulating properties. If they were ever run wet or dirty, they may be carbon tracked. Most black rubber contains carbon black, which is a conductor . Carbon black does not decay, but rubber does, and old rubber insulation might be expected to have poor insulating qualities at high voltages, even if it's never been used.

Kurt

when the crank pin is at 9 o'clock/3 o'clock (absolutely parallel to the ground) you have SOME cylinder at TDC...doesn't even matter which one...

follow this: http://dauntlessgeezer.com/DG97.html to find 15 degrees ATDC and set up the timer

the instructions tell you to look for compression on #1, but even that is overkill...setting static like this doesn't matter which cylinder is under compression as the timer has 4 contacts and SOMETHING is going to buzz...what is good for one is good for all (in general).

Throw the "tin with rubber sleeves" in the garbage. Has no place on a Model T.

Wouldn't do that to an old time Model T accessory......keep it, someone will want it as a display/wall hanger

DanTreace wrote: ↑

Wed Dec 22, 2021 6:17 pm

Throw the "tin with rubber sleeves" in the garbage. Has no place on a Model T.

Wouldn't do that to an old time Model T accessory......keep it, someone will want it as a display/wall hanger


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Yes Dan, you're correct. I honestly didn't realize it was an actual T accessory. I thought it was a home made gizmo. Still think it will not help the OP's situation to leave it installed.

To answer the authors question, according old literature, 10,000 volts is required to start a model t. This equates to a spark gap of about 125 inches.

Art Mirtes