I'm sure this has something to do with car starting on mag or something but I'm not familiar being a fairly new t owner. I've had the same thing happen last year with my other T as well.
I had pulled into the gas station for a refill. Turned key off pulled park brake and filled with gas. Went inside and paid,came out and while getting in "through pax side" reached to turn key on and the car started right up. I wasn't real surprised because my 27 did it last year in my garage. I continued on my trip with 16 other cars and after about a hundred miles arrived home with no problems. My question is would this have something to do with the spark being more advanced than it was supposed to be when I shut her off or something else. I know some will say I probably shouldn't be driving a T if I don't know the answer to that but a wise guy on the forum once said that there is no stupid question relating to a T. "I have lots"
thats because these have brains of their own.
I think it has to do with un-burned gas that remains in the cylinder, thereby starting the car on compression. It's loosely termed a "free start". Mine has done it at least on occasion up to 10 minutes after shutting off the motor. Other times I can get one just about every time.
If you hand crank the car with the switch off and choke it a couple of times, then turn the key on, it will probably do the same thing. Mine does.
I'm beginning to think so. Hope she doesn't start talking back to me. She does cough every now and then.
Good to know. I've never heard of a free start before.
It's what we call a "Free start". Some are more prone to it than others. It has nothing to do with the mag. It only happens on battery. It is because when a coil is buzzing, it is throwing a spark at the plug. Unlike a distributor where the points have to be mechanically opened to get that one single spark, a T will spark anywhere over a wide range of piston positions. As long as there is a combustible charge in the cylinder and the piston is past TDC, there's a good chance it will try to start. Sometimes it tries, but only coughs. Other times, nothing. It seems to do it most when you don't want it to, like when trying to demonstrate a hand crank start.
If you consistently get free starts it means the timing and mixture is set properly. It's a normal thing for a properly tuned Model T.
Free starts can be fun.
Had one on a car I worked on this past week...surprised the heck out of me as it was a Distributor equipped car!...
Was chasing an issue and my fault, turned the key on, and only then decided to advance the Distributor mechanically by a bit at the housing since the advance lever had previously been disconnected by someone. Yup, Petronix must have 'opened' as I nudged it... I was more surprised by the feeling of the fan hitting my knuckle that it took me a further second to say 'wow...free start'!
Don't think I'll do that again!
This is what Ford Motor Company said about starting "on the spark", in 1907:
As the article says the best way to get a free start is by opening up the throttle fully as you turn off the key. That gives you a full charge of gas to ignite when the key is switched on. It also helps if the motor is well broken in as a tight motor will often just cough but not start. After a rebuild it usually takes over 1,500 miles before the free starts kick in.
Hi" I have an old trick that was shown to me by a old timer. If your car "free starts" most of the time you will know at what position the spark rod and throttle need to be in. I have mine set to free start about 3 "clicks" down from all the way up or retarded position. That way you can push the spark all the way up and then turn the key on with out the motor starting. I have a lead weight made that has a wire hook on it that I hang on the spark rod. It has been made so it is all I can do to hang it on the spark rod without it pulling the spark rod down. Kinda like setting a mousetrap. I also have a small pillow or towel ect in the floor for the weight to fall on. My car useally starts for up to 15 to 20 minutes after stopping the engine. With the mousetrap set and the key on I wait for someone to either shake the car step on the running board ect. The weight will fall from the movement and start all by itself. Its fun to see the expression on there face. Ill also be talking about the car and when the time is right just kick the tire. The car useally starts on its own. Ill say "Looks like Lizzie is ready to go" get in a drive away. Just remember to always have the parking brake set. Free starts are a sign of a good condition engine (pistons, rings, valves) Donnie ....
Our 12 free starts almost every time we get gas when it is warm it has sat for 2 weeks and free started and last year it sat all winter and in the spring I set it up an it kicked but did not start.
I had second thoughts about posting this thread but I'm glad I did. I've learned a lot as usual.
I have two cars that free start quite regularly. Both are older rebuilds and kind of loose. One "chuffed" the other day when I turned the key after sitting for 8 or more days. My tighter engines never do that.
It is always a treat.
It's funny. My T will only free start when it's stone cold. It will be 40 degrees outside, and with a few primes, it will free start. If it's warm outside or the engine is warm, then good luck!
I get free starts about 50% of the time.
Since I don't have a starter it makes things easy for this old guy!
With the ignition off, I open the throttle about 1/4 and give it a few good pulls while choking it.
With the spark retarded, I turn the switch to battery. If it doesn't start I then advance the spark.
I just started Lizzie for the first time since the OCF and it was free!! Bud.
Enos....again..... The only dumb questions are those unasked. Even though I knew the answer to his particular question, as a fellow newbie, I always learn something from questions asked.
It has to do with what the position of the crankshaft is when the engine was shut off. It has to stop just after top dead center so that when the spark comes it will turn the engine forward. If it stops before top dead center, it will try to start, but kick. The spark lever should be up when you turn on the ignition so that it can't spark unless it is after top dead center.
I definitely learn a lot from asking questions here and reading all the threads every evening.
Being a T owner for only about a year I still have a lot to learn.
Imho,i think the spark lever should be up or at full retard at shut off to get more free starts.Bud.
I always retard the spark before shutting off the car and open the throttle as I turn off the switch. I get lots of free starts that way but more importantly I never have to remember to retard the spark the next time I go to start the car.
I think free starts should be avoided if possible and not sought after. Too much stress on on the old lady's 100 year old crank. I'll take them when they happen though.
I don't think a free start will be anymore stressful on the crankshaft than a start with crank or starter, however, if you open the throttle as you turn off the key, you flood the cylinders with unburnt fuel which will just dilute the oil on the rings and cylinder walls. This will wash off the lubrication leading to "dry starts". Dry starts cause faster wear on the cylinders and rings.
Thats' why you should always take the key out when you park them at a show or a T meet. One small kid or a dumb old man + a free starting T could be very bad in a hurry !
Had a close friend reach over into his 1926 touring that had been sitting for a week he turned the key on she fired up he rode it out of the garage standing on the running board, good thing he had been driving them for 50 years and knew what to do.
Steve makes a very good point - Always expect a free start when you turn the key on.
There may not be a free lunch but our T's sometimes give us free starts.
Since Halloween is coming, watch out for delayed starts. They are spooky when you turn the car on, the coil buzzes, and just as you are about to grab the crank, it starts!
Yep. Had that happen before, as well.
The first time I got a free start it scared the hell out of me.......LOL
Eight starts today and seven of them were free! Only the first start required cranking. I admit that I was running errands and made several fairly short but the last one was over an hour. I ain't complaining and I am prepared to run the risk of a broken crank. It beats a broken arm!
Frankly, I enjoy hand cranking.....assuming it's not being obstinate. My TT has a starter, but I seldom use it, even in the privacy of my own shop where there're no onlookers to show off to. I forget I have the option. 'Course, the '18 Touring has no starter. At any rate, I occasionally do try for the free start when my bad ankle is acting up and I prefer to minimize the amount of walking I have to do.
I agree with Norm - don't see how a free start adds stress to the crank
I had a completely unexpected free start this morning. The car hadn't been run for about a week and a half. 55 degrees in the garage. Fully retarded, ~3 notches of throttle. No choke, no cranking at all. As soon as I turned on the ignition it fired right up! Surprised the heck out of me!
My frequent free starts make me extremely happy, for they are a good indication that everything is as it should be, well tuned and in perfect running order. Jim Patrick
Of course, when you want to show off to the crowd that gathers around your car and hand crank it, all you will get are free starts.