Commutator timing help required

[bagotcorner]

It occurred to me while in a conversation with another gentleman that the lever when at full up position is far too retarded to likely even start the engine .
I’ve rarely had much luck getting an engine to fire much past the piston heading too far on its post compression downstroke .
And if it was , it wasn’t enough to spin the engine through compression to the next power stroke .

I started reading and found this from a mark osterman.

“When cylinder number one is on the compression stroke you�ll see the top of the piston come up all the way ... then pause ... and start on the way down. When the piston starts going down I quit cranking. I then retard the spark lever all the way and turn on the key. Then I reach down and turn the timer until I hear the number one coil I buzz. Then I bend the rod to fit the timer connection.”

Now this made sense .
Never mind the bolt to arm measures etc.
It seemed full retard should be just barely into the downstroke of then piston .

Now before I bend the arm to fit .

Do the words of Mr osterman make sense to everyone ?
As it was , my full retard position had it firing half way down the cylinder before the exhaust stroke .

Thanks , Vince

[Jugster]

This video should help...

https://www.youtube.com/watch?v=sMi8uIc ... WL&index=1

[Norman Kling]

Halfway down is way too far retarded. The spark must come shortly after the piston passes top dead center or it will try to turn the engine backwards and that's what will break your arm or the starter. Once it is moving faster, you can advance the spark and the flywheel will keep it spinning fast enough to turn the engine the right way.
Norm

[bagotcorner]

Yes most def it was way too far retarded .
I’ve had many many years experience with hand cranks on antique engines and know those dangers of advanced spark on start up .

So , using the 2.5” method looks def better than it was , but still quite retarded .

I may leave it there ,,and bend the arm to fit .
As it was ,, here is a photo of how far the timing lever would have to be to be in the commutator hole .
So , I have a little bending to do .

The way it was , I’d have had that lever half way down till it fired right at tdc .

Obvious someone didn’t have it “dialed “ in

[Mark Nunn]

Here is Steve's step-by-step method.

https://dauntlessgeezer.com/DG97.html

I use a dial indicator and set timing at 15 degrees retarded. The piston should go down .087" from TDC.

TDC timing.pdf

(11.49 KiB) Downloaded 68 times

[Ron Patterson]

This article Steve Coniffif and i wrrote several years ago will help explain how and why the Model T initial spark advance was set from the factory.
Hope this helps.
Ron Patterson

[Humblej]

Vince,
Do Not use the 2.5 measurement unless you know for sure you have a Ford timer and Ford roller. All timers are not the same. Following the procedures already described by others will set any timer correctly.

[bagotcorner]

This article Steve Coniffif and i wrrote several years ago will help explain how and why the Model T initial spark advance was set from the factory.
Hope this helps.
Ron Patterson

Excellent article .
It dovetails well into my knowledge of setting magneto spark timing ( on ignitor) hit miss engines for optimal spark (on point break as opposed to contact )as compared to using a buzz coil which is essentially instantaneous .
With the absence of a rectifier I assume the mag puts out ac voltage correct ?

Thanks for the article .

Vince

[bagotcorner]

Vince,
Do Not use the 2.5 measurement unless you know for sure you have a Ford timer and Ford roller. All timers are not the same. Following the procedures already described by others will set any timer correctly.

Thanks for the heads up .
I found this measure erroneous as well .
If I had used it I’d find my piston position on full retard to be half way between tdc and bdc .
It likely wouldn’t have fired and I’d be beginning a side journey into frustration ! Lol

[TWrenn]

The simplest method is what John Regan taught me via email...called the "9:30-3:30" method. Being the position of your crank pin, with the #1 piston on compression. You can determine that by simply slowly cranking the engine by hand with your thumb over the spark plug hole. Steve Jelf put out a video on this method also. PM me and I'll email you what John sent me, it's too much to detail here, but it really works and is very simple to do. From this method my '13 will start usually on one "quick yank" after the usual priming and a couple of "non prime" yanks first, if it doesn't even free start after that. Don't make it complicated.

[bagotcorner]

The simplest method is what John Regan taught me via email...called the "9:30-3:30" method. Being the position of your crank pin, with the #1 piston on compression. You can determine that by simply slowly cranking the engine by hand with your thumb over the spark plug hole. Steve Jelf put out a video on this method also. PM me and I'll email you what John sent me, it's too much to detail here, but it really works and is very simple to do. From this method my '13 will start usually on one "quick yank" after the usual priming and a couple of "non prime" yanks first, if it doesn't even free start after that. Don't make it complicated.

Thank you !
Yes , I mentally compared your 9:30-3:30 method and I figured it was the same essentially as the Steve Jelf method .

I have a slight adjustment to this which shouldn’t make a difference .
I use the Audible on my multimeter ohms setting to check continuity between the commutator 1st cylinder pole to ground .
Which ,, would also fire the trembler if it were connected to a battery ( I have them all out of the truck currently .

My cup is badly wore on the crank ( it will have to come off to be able to sort belt alignment )
But by taking the lash out I’m coming up with that 3:30 position ( lol maybe 3:40)

Thanks vince

[TWrenn]

The simplest method is what John Regan taught me via email...called the "9:30-3:30" method. Being the position of your crank pin, with the #1 piston on compression. You can determine that by simply slowly cranking the engine by hand with your thumb over the spark plug hole. Steve Jelf put out a video on this method also. PM me and I'll email you what John sent me, it's too much to detail here, but it really works and is very simple to do. From this method my '13 will start usually on one "quick yank" after the usual priming and a couple of "non prime" yanks first, if it doesn't even free start after that. Don't make it complicated.

Thank you !
Yes , I mentally compared your 9:30-3:30 method and I figured it was the same essentially as the Steve Jelf method .

I have a slight adjustment to this which shouldn’t make a difference .
I use the Audible on my multimeter ohms setting to check continuity between the commutator 1st cylinder pole to ground .
Which ,, would also fire the trembler if it were connected to a battery ( I have them all out of the truck currently .

My cup is badly wore on the crank ( it will have to come off to be able to sort belt alignment )
But by taking the lash out I’m coming up with that 3:30 position ( lol maybe 3:40)

Thanks vince

Okay Vince!
Sounds like you're on the right track!

[Will_Vanderburg]

The bolt to timer measurement only works on Ford roller timers. Maybe Tiger timers, too

Also, that timing tool sold by vendors is flat. It’s actually supposed to be bent

[Norman Kling]

I don't think this was mentioned, but is crucial to get good response to the timing lever. All connections must be tight with minimum play so that the when the lever is all the way up, the timer will be all the way retarded. and when the rod is down it is all the way advanced. Otherwise, moving the lever might not make as much difference in the position of the timer. Also when driving on magneto, it is different from battery. The spark comes as the current on the magneto sine wave builds. So it will be sometime later than it is on battery which spark comes as soon as the roller or brush makes contact. That is why when driving on magneto you can move the lever and notice no difference until you reach the point where the next sine wave begins to build up and then the spark will suddenly advance. There are at least 3 of those points between all the way retard and advance. On some timers there will be 4 points. When driving on battery, it will advance continually as you move the lever down, so the best location for your driving conditions will be different on mag than on battery. You will actually get a slight automatic advance with speed without moving the lever.
Norm

[Dan Hatch]

Again, here is the back in the day method.

Here is the manual.

[Allan]

I have 7 T's. The position of the lever at the quadrant varies from car to car. What is obvious is the amount of travel at the quadrant more than adequately covers the range of adjustment needed to operate a T at it's optimum. So, as long as you can get the amount of lever adjustment required to operate your car, it doesn't really matter where fully retarded is, as long as you can get fully advanced when needed.

When I put Henrietta back on the road following her 62 year slumber, I found I had to give her almost 1/2 the quadrant travel to start her, and whack the lever hard down to get her to optimal advance. I do need to remember to give her that 1/2 quadrant start. Any less and she is reluctant to fire up. I probably do need to adjust the length of the connecting rod, If for no other reason than it would mean I did not have to remember where to set the lever at starting time.

Allan from down under.

[bagotcorner]

I have 7 T's. The position of the lever at the quadrant varies from car to car. What is obvious is the amount of travel at the quadrant more than adequately covers the range of adjustment needed to operate a T at it's optimum. So, as long as you can get the amount of lever adjustment required to operate your car, it doesn't really matter where fully retarded is, as long as you can get fully advanced when needed.

When I put Henrietta back on the road following her 62 year slumber, I found I had to give her almost 1/2 the quadrant travel to start her, and whack the lever hard down to get her to optimal advance. I do need to remember to give her that 1/2 quadrant start. Any less and she is reluctant to fire up. I probably do need to adjust the length of the connecting rod, If for no other reason than it would mean I did not have to remember where to set the lever at starting time.

Allan from down under.

Hi Allan,
Yes, I was wondering why you didn’t just set the perfect amount of retard to be at the top for starting , and then adjust advance downward from there.
But, if you know, roughly where you need to be to start it, and no one else is driving it then it only matters what works for you.
Mine was set up the same way and optimal start. Timing would have been about a third of the way down the quadrant..
Me being a new t owner, it would’ve confuse me to not have that as simple as possible.
Thanks, Vince

[Ron Patterson]

The objective of our article above was to simply explain how the Ford magneto ignition sustem works.
The article was not intended to identify all the problems with every Model T's in existence today.
If your Model T has an improperly installed water inlet pipe from the radiator to the drivers side of the engine, has an improperly routed timer pull rod, has a loose timer pull rod lever at the end of the spark rod, the system will not work as intended and you have to correct those problems first.
The CORRECT initial timing setting for any Model T timer, regardless of type/kind when the spark lever is fully retarded is 15.5 degrees ATDC.
That was cast in stone with the first Model T and never changed throughout production. This was done so to accomodate easy hand crank starting on the magneto. The Model T was not eqipped with a battery for starting until 1919.
Changing the initial timing should be accompolished by changing the length of the timer pull rod.
I agree with the comment that the crank position at clock face 9:30 and 3:30 method works very well, but on some cars viewing the crank pin is difficult. For those nor familiar with thei method; when the crank pin is exactly horizontal (9:00 and 3:00) one of the four pistons is exacly at TDC. When the crank pin is at 9:30 and 3:30 one of the pistons is at 15 degrees ATDC.
Everyone has their own method of accompolishing this, but the technical explanation our article and the considerations above are 100% correct regardless of what kind of timer you have or use.
Ron Patterson

[Ron Patterson]

Thank you Vince!

[Ron Patterson]

John Regan had a fovorite saying about fixing Model T's: "The car is 100 years old and 100 people have been working on it. what are the chances they all knew what they were doing?"
A Model T can be made to run with many thing wrong, but that doest make it working as intended.
Ron Patterson