Given the recent discussion about hand cranking, I want to ask this question again. Iíve asked it in the past, but never got an answer I really understood.
Why should you put your thumb on the same side of the crank as your fingers?
I really donít understand why. I do not do this. I use my right hand and I wrap my thumb just like some say not to. I always start about 7:00 and pull up. I never push down or try to ďspinĒ the engine. I always make sure the spark is retarded. I do my own maintenance and know how to properly adjust the timing. I feel very confident in my safety awareness and while I respect the vehicle, I do not fear it. Someone on another thread who had been injured made a comment to the effect that if you think you wonít ever be bitten by a kick back, that you might had better think again. Perhaps Iím one of the ones he was speaking to. I wonít say that it will never happen. I suppose anything could happen. I could be hit by a dump truck on the way home today, but I wonít let that keep me from driving home.
Given all that, I understand that a kick back can occur. I understand that if it does, youíre much less likely to get hit by the crank if youíre using your left hand. I understand that one. Even so, I use my right hand. Iím right handed and I doubt I will change. Although, this is my first T, Iíve hand cranked a tractor for many years. With its compression and height it is sometimes necessary to use both hands. But I digress. What I really donít get is what a kick back is going to do to my thumb that itís not going to do to my fingers? The way I see it, itís going to pull the crank out of my hand by forcing my fingers to open up. Is that not the same thing itís going to do to my thumb? Iíve gotten answers in the past like ďIt will break your thumb.Ē Or ďIt will pull your thumb out of joint.Ē OK, letís assume that is true, please tell me mechanically or geometrically, what about a kickback is going to do this to me? I really donít understand it.
PS, I know I probably sound self righteous. I really donít mean to. I truly do not understand what the thumb thing is really all about. I would just like for someone to explain it to me so that I will understand it.
I used to ask same question. Then I had a coil ride up in coil box and short over to another coil sometimes creating complete mis-timed firing of cylinder. I found that crank would tear out of my hand when held "correctly". I suspect that if my thumb was wrapped around my fingers, I'd likely not release crank as quickly, pulling me, my wrist, and face closer to crank when revolving backwards.
I had just purchased car, and shorting was intermittent. Took me quite a while to chase that bugger down, but when I did, it was so obvious that I warn nearly everyone about that issue (coils shorting on inside of lid).
Yep, almost same thing here. Forgot to make sure everything was ready for starting and had the crank RIPPED from my hand. Ouchie.
My dad told me his father broke his arm cranking a T. I had my first T in 1970 (12 years old), and dad always made me crank keeping my thumb and fingers together, for this reason.
I've had the crank "whipped" out of my had a few times, but never any injury. I don't know of a good reason not to crank like this.
I crank our T's with my right hand, but our 13 Buick and Ford N have chokes on the right side of the radiator, so I crank them using my left hand, and I think this is actually safer, because if the crank "kicks back", my arm/body/shoulder are not in the line of fire, compared to using my right hand with our T's.
As long as you're always pulling up and your thumb and fingers never go past the 12:00 position, you are probably safe from loosing your thumb in a kickback if you are using your right hand. The problem with using your right hand is the second revolution of the crank spinning backwards and hitting your wrist if you don't get your arm out of the way quickly. More problems to follow in a later paragraph.
If you use your left hand, the kickback will still drive the crank into your hand anywhere after about the 10:30 position. This is when the thumb tends to be moved in a painful manner.
Never say that your engine will not kickback. As practiced as we all claim to be, accidents and brain faded happen.
By keeping your thumb alongside your fingers everytime, you lessen the chance of potential damage should you have a momentary lapse of judgement. If there is a kickback, the force will automatically open your hand and release the crank.
With the thumb rapped around the crank opposite of your fingers, you will have a much stronger and firmer grip on the crank handle. In this case, if there is a kickback, your brain and hand will have more of a tendency to fight the kickback instead of releasing from it and avoiding any injury to the arm and/or shoulder. The end result will be something like the feeling of your arm being torn from the shoulder socket. OUCH is all I can say.
In the end it's your hand and arm that will feel the pain should you ever learn the hard way why this lesson has been taught since before the Model T.
When that thing kicks back, even Muhammed Ali's right hand wouldn't be fast enough to get out of the way.
I crank with left thumb over the crank, and I don't fear breaking the thumb, because if the crank kicks back, it will be below 9 o'clock, so no force can be put on the thumb.
The brain hemispheres control opposite sides of the body.
That's why we left-handers are the only ones in our right minds.
And the ones who don't break our arms cranking.
Here is the medical term for that broken hand by cranking the Model T with your wrong arm and wrong grasp of the crank handle:
Radial styloid fracture
A Hutchinson fracture, an isolated fracture of the radial styloid, is typically caused by a direct blow to the radial aspect of the wrist. It may also be referred to as "chauffeur's fracture" or "backfire fracture," as it initially was described in individuals struck by the hand crank on early automobiles when the engine suddenly backfired during starting.
Chauffeur fracture (backfire fracture, Hutchinson fracture). Frontal radiograph of the wrist shows a vertical fracture of the radial styloid process (arrows).
Be sure to keep the thumb and fingers togther, and just 'cup' that crank handle in the left hand when you pull up on the crank, after checking the retarted positon of the timer lever. Or you may be seeing your own wrist in an x-ray sometime!
You've asked a good question, Hal, and I'll tell you what I think. Lots of this was gleaned from the old-timer who sold me my first T.
If you hand-crank by pulling up, starting around 7:00 or so, and you STOP pulling at about 11:00, it probably doesn't matter so much where your thumb is, although using the left hand would appear to be safer than the right.
But, if you "spin" the crank past about 11:30, so you are essentially pushing DOWN, and it kicks back, that would be when it makes a tremendous difference where your thumb is. In theory, that scenario could possibly tear your thumb right off.
Back to the right vs. left hand. If you look at the Ford picture that has been included in this thread, you can see that if the crank isn't spun, but only pulled up, and it not only kicks back but actually spins all the way around backwards, its initial action of throwing your hand OUT of the circle would be safer than if your right hand were still dangling in the circle when the crank came around.
Or so I was told.
That's part of the reason I kick-start. As I said before, I'd a whole lot rather have a broken leg than a shattered arm, and when I stand up to stomp the crank, I'm looking the spark lever in the eye! And, I feel a lot more stable standing up and holding on to the radiator neck, than leaning over with nothing particularly solid to hold on to.
Finally, I can spin the engine a whole lot faster with the strength of my leg, than I suspect anyone can with their arm. Especially the tenth or twentieth try!!
P. S. I know you said in your question that you do not "spin" the engine, but my discussion was more general than just for your particular case.
Well, Dan had the solution right there all of the time
T's are meant to be cranked left handed! But I have to question where you put the right one if you just drove 20 miles or so....
With Thumb under and cranking left handed, and being in tune so there is a quarter pull...then the hazard is in fact eliminated!
1- on a kickback, it simply unfurls the fingers and throws the hand out of the way before the crank gets to wallop [most of the time].
2- Should a kick back be strong enough to corkscrew the crank 720 degrees or so backwards...the hand is already out of the way.
Good golly miss molly....darned....should have just read the original instructions...wife always does accuse me of forgetting that step.
OK, let's hear comment from those 5 foot tall fireplug built, summo wrestler guys who always insist on spinning with both hands
I must be missing something here, I assume you would have kickback if handcranking on battery power and the spark is advanced.
I've never had kickback handcraning on magneto.
There's a youtube video that shows what a kickback looks like:
I've only had one kickback, and I wasn't injured, but it felt like an electric shock had gone through my wrist and arm. I crank right handed and fortunately was not hit when the crank spun back around. Kickbacks are violent and without warning. You don't have a chance to react to them.
And yes, the reason for the kickback was that I had forgotten to retard the spark. It can happen easier than you might think if you are fiddling around with the engine, or trying different things to get it started, or are distracted with visitors, or shut down and forget to retard the spark, etc.
I understand what a kickback entails, just stating that I've experienced no problems with cranking on magneto.
This is from a 1910 Audel's "Operation & Maintenance of Self Propelled Vehicles" I got it for what was to be my future Father in Law to make points. Even tells how to change a boiler in a Stanley.
Only I notice is a little strange, is that the instructions tell the crankee to pull the crank to the top & push down.
The two golden rules I learned before I even had my T driveable were 1)don't slip the bands, and 2)crank correctly (as in fig. 40 in the previously posted pic).
As my car has such low compression and very retarded timing with the lever all the way up I've never even come close to having a kickback; even if I've forgotten to back off the timing before cranking (it won't even fire then). I also don't have the throttle set much above idle so if the jack under the back wheel falls over the car will stall (hopefully).
Some people, it seems, like to have their timing set so it's a bit advanced, even with the lever all the way up...I once tried to crank another T like that and once I felt that kicking I refused to continue trying to start it. That kickback is totally unforgiving and nothing will stand in its way. Given this particular T was fitted with a 12V battery (it was discharged hence the hand cranking) feeding the starter and had permanently advanced ignition I expect something will break sooner or later.
Watching supposed "T experts" wind the crank around 360 degrees or use their foot just fills me with horror, but one day they'll learn.
I was looking through some parts and was again reminded of the violent nature of a kickback. What I was looking at were the remnants of a bendix spring after one such kickback.
I keep these parts to remind me and show others the energy your body must deal with during a kickback if you hold on too tight or get too close.
Be careful out there.
This summer, while at a car show, my kids along with others were crawling over our car. I always set the spark and gas for starting when I shut off a car, so I can just turn on the ignition, go up front and crank.
On this particular occasion, I turned on the switch, went up front (with a small crowd watching, much to my satisfaction), pulled the crank, and sure enough it kicked back like nobody's business.
I looked glaringly at my kids in the front seat, because the spark had been pulled down, along with the throttle. Of course they didn't do it (probably didn't, because they know about not changing things on the cars), but probably one of their new found friends did.
As a result, I decided no car is "kickback" proof.
BTW, it was our N, but it still packed quite a 'kickback" wallop.
Another question I have, our 13 Buick has an impulse mag, along with a DU-4 mag, and it never seems to appear as if it will kickback. I wonder if the impulse mag prevents such an occurance from orruring (start on the impulse mag, then goes to the Bosch mag, like old tractors did)?
Alas, it is a common thing with kids all the world over - it is always their friends "Ida No" or "Wuzzan Mee"
Sigh - but then again we NEVER did anything like that ourselves did we ;-)
Yes Rob the impulse on your DU4 retards the spark internally and when it starts it goes to the advance position. The impulse winds up before it lets go so the mag snaps over faster to start. I run 2 on overhead T's and never touch the spark--just engage the impulse to start the car.
I have been bitten before and had to go to the emergency room. I was at the local ice cream shop. Lots of kids around so I thought I would entertain them. I retarded the timing fully, got in front and pulled through. It didn't start. I pulled again and BAM! Good thing I had my thumb on the correct side. I only got a slap (hard) on the back side of my hand. Had my thumb been around I would have broken it. What happened is after the first pull through the timing lever slipped down and I didn't check it. I now have a Texas T Parts wood block tensioner on the timing and throttle linkage arms so it doesn't move. Once bitten twice shy. Spend the $10 or make one. Or be sorry or is that sorey By the way - they were entertained and the car did start.
Think of all the doctors that would have had less work, if it weren't for Model T cranking fractures. Equipping the T with a magneto with impulse coupling would have been so easy, and no doubt lower cost than the buzz coils and internal magneto. The cost of patent royalties was probably not as big a factor as Henry's stubbornness in refusing to pay them.
LEFT! LEFT! LEFT!
It's hangin' there. Learn to use it.
You can use a glove or old towel so to put your right hand on the hot radiator to steady yourself.
That old Audel instruction must have been written by a greedy doctor.
Year before last, at the National City Automobile Heritage day, I was in a row with a 1903 Knox, It had a one cylinder air cooled motor, the one cylinder was about the size of T's motor, it had a 15 pound detachable crank, If it kicked & the crank flew you wouldn't just break an arm, if it didn't kill you, you'd be going through a lot of reconstructive surgery.
Nice thought, Alex. If the engine is turning backwards, the crank will stay on the shaft. It's when the engine turns forward faster than the crank that it will disengage, maybe with a vengenace.
Long time ago, my Grand Dad was cranking one of out T's, I was sitting in the front seat, told me to "give it some gas", and guess what, I pulled down the wrong lever. Got a cussing and a whipping that I still remember ! Remember Bay Bridge Sue ? she used to write about spinning her's to start it, I have done that too, but a very long time ago on cars that were flat wore out.
Grady, that's funny! ;)
Michael, not funny at the time !
RD,Do you get alot of free or compression starts with a mag wheather it has a impulse or not?? As a boy who used tractors with hand cranks and mags with impulse everything was not perfect and they would break and also stick.If the cranker did not retard the spark and the engine kicked and injured them would it be the engine's fault or the Dummy who forgot?? Would it matter what brand it was say maby the Cadillac or others without Shower of Sparks?? Yup,The Ford broke proably thousands of thumbs,hands,wrist,arms,jaws,and maby worse but how many Fords were sold?? How many people in the day forgot to retard the spark as people Still do?? PS,Thanks george!! Bud DeLong.
You could just attach one of these special devices back in the T days before the electic starter....
Dan,I wonder if anyone made a Shower of Sparks for the Ford?? Anyone who ha seen OLD 16 started has to belive there was a better way! I also wonder how the 999 started and were it and The Arrow the same car just reworked? Bud DeLong.
Those look like flyweights on the magneto, and they were no doubt used for centrifugal advance.
Perhaps I'm just hard headed. You have me totally convinced that a T can kick back. You have me totally convinced that if it does, there's a good chance the crank will break your writst/arm. You have me totally convinced that cranking with your left hand is safer than cranking with your right hand.
However, I still don't get the thumb thing. The best explaination to me is that you will have a better grip which may pull you down further into the arc of the crank, therby inceasing your chances of getting hit when it comes back around. Perhaps this is all there ever was to it? I don't know. But I still don't see how it would break my thumb or pull it out of joint, and SURE don't see how it is going to take it completely off.
Sorry guys. I'm REALLY not trying to be hard to get along with. I'm just one of these guys who has a need to understand things rather than taking them at face value. At least most of the time. This is just one of those things that has me baffled and I was wanting to get a better understanding. And I still don't get it.
Hal, I'm just guessing myself, but if you have a tight grip on the handle with the thumb wrapped around it, it will pull you down and into position for a bad rap on the arm or head. If your palm is open, it will only slip out of your grip and you will likely pull up. We used to get men with "corn picker" injuries as they tried to dislodge clogs in the picker by stabbing at it with a corn stalk. None of these men would dream of reaching into the header, but use the longest stalk they can find to stab at the clog. As the picker grabbed at the stalk, they couldn't let go fast enough and it pulled their arm into the mechanism, often taking the arm off at the elbow. Your reflexes just aren't fast enough to let go quickly.
The thumb on the same side is to reduce the hazard when you're cranking wrongly. If you're pushing down with your right hand, a kick will take it out on your right thumb.
I grip with my left thumb in the normal place, and have even overpowered kicks that are very near TDC.
If you pull up with your left hand, the thumb and the whole hand will be out of the way as the crank comes swinging back around. Because you're pulling up at about 9 0'clock when the kick pulls the crank out of your hand, your hand will keep coming straight up, and out of the way.
Left is right;
Right is wrong.
Owwee won't be your song.
We grind cane for syrup. The cane mill doesn't turn real fast, so there's no real chance of it pulling you in with a normal length piece of cane. BUT...Sometimes, a real short piece will break off and be blocking the rollers. You have to fight the urge to reach in and get it out. It's just a natural reaction. If you got into those rollers, it would pull you right in. It is a nip point by design and no guards on this thing. It's likely as old as a T. The other hazard is pushing the cane in. Sometimes, you have to ram it in pretty hard to get it to start between the rollers. If a piece breaks while doing this, you could fall into the thing. They are dangerous, but like a T, a lot of fun also. You just have to be careful working around this old stuff.
How much horsepower is in the kickback? I was thinking that there was 5 HP since only one cylinder kicks back.
My wife is left handed, that is why I let her crank our 16 Seriously, after reading all of the above posts, I am getting concerned about one of us having an injury cranking the car. Maybe when the time is right for a rebuild I will add a starter.
Howard, It may only be 5 HP of kick but it is concentrated in just a few square inches of crank handle. I broke my two fingers in seven places and also separated the fingers at the knuckles on a Holsman engine and it is only 12 HP. Maybe the 55 pound flywheel helped a little!....Michael Pawelek
Only 5 hp? Think of it as five horses all kicking you at once.
Here I go again; purely conjecture on my part. But I was taught to always keep my thumb on the same side of the crank as my fingers; and I have always done that, even tho' I may have been doing it unnecessarily, or for the wrong reason that I had in mind. Here's my theory, and, as I said, just my idea:
I think Ralph Ricks has come as close to the real reason as anybody with the first sentence in his comment:
"....to reduce the hazard when you're cranking wrongly".)
I think (as I said; conjecture on my part) that a lot of people, back in the early days of the Model T, in fact, maybe this started back even earlier with the A, R, N, or whatever, when people who had no previous experience of any kind with automobiles, engines, or mechanical things of any kind, actually (and mistakenly) thought that to hand crank a gasoline engine to start it, you had to "wind it up" by first pulling up on the crank, and then over top center, continue to spin the engine by pushing down on the crank, in a continuous winding motion of several non-stop revolutions until the engine began to fire. Now, stay with me on this; imagine what you'd be doing on each revolution during the portion of the revolution when you pushed down on the crank. You are not really "gripping" the crank all that hard, if at all. You are mostly pushing down on the crank with the heal of your hand. I'm sure there were many "kickbacks" (maybe more in the early years because these newcomers to gasoline engines didn't always think to retard the spark) and if that kickback happened to occur on the downstroke when not gripping the crank all that much, but if your thumb was wrapped around the crank, a broken arm or wrist would commonly occur. Someone, who also did not know that continuous winding up of the crank/engine to start it was not necessary, realized that if your thumb was on the same side as your fingers, and the kickback occured on the downstroke when you were barely gripping the crank, but mosty pushing down on the crank with the heal of your hand, the kickback would harmlessly rip the crank out of your "non-gripping" fingers and not break your arm. (Whew! not sure I could say all that again!)
Anyway, I think (remember, purely conjecture) I think that by the time that more people learned that you only had to pull up on the crank from approx. 9 o'clock to 12 o'clock to start an engine, the common practice of keeping their thumb on the same side of the crank as their fingers had already become "a rule of thumb" (no pun intended) and from those early days when so many people were still "winding up the motor with the crank, the rule just stuck, whether it was necessary or not.
So, that's my theory of how, and when, this "rule of thumb" came into being. (Hey, maybe that IS where that expression came from too (???) Anyway, that's my story and I'm stick'n to it! For what it's worth,........harold
Here's my 2 cents on the "rule of thumb"
If the thumb is on the same side of the crank as the other four fingers, when the kickback occurs, the hand is thrown out of the way.
If the thumb is on the opposite side of the crank as regards the other four fingers, the thumb acts as a restraint to keep the hand from being thrown out of the way, UNTIL something gives in the thumb or the wrist to enable the hand to be thrown out of the way. Only then, it is too late. And it happens quicker than the blink of an eye. Trust me on this one guys. LOLOL Besides, when the thumb is opposite the fingers, instead of with them, you're going to grip the crank more firmly (wrapping thumb and fingers around crank) which makes it all the more dangerous.
Like I said, my 2 cents, FWIW.
Given the LARGE number of "old timers" giving the same advice (often from experience) with regard to cranking stationary engines, tractors, cars, trucks, binders etc etc I think there must be some sort of reason for the advice NOT to wrap the thumb around the crank.
One thing about advice - you can listen to it then decide for yourself!
Experience lost is another lesson for someone else to re-learn.
When I had my first T in the 50'S, I was showing off to a girl. I didn't have a starter or generator in my 26 T. Thatís what you get for $10.00! I would need to spin the engine to get it going. I put my hand around the crank and started to spin the crank with my thumb around the crank. It may have been wet or shorted in the timer at the wrong time and backfired.
All I know, had I been older I would have had a broken arm or wrist. It jammed my arm into my shoulder so hard that it upset my stomach and I lost my cookies. I really impressed the girl. I lost her also. That was the last time I wrapped my thumb around a Crank. I still can spin an engine and get most of them running on mag, but never with my thumb on the opposite side of my fingers.
I have had the crank ripped out of my hand many times. Other than your pride and a little sting in the hand you wonít get a broken arm.
Thatís my story and Iím sticking to it.
I enjoyed your story. My question is, I've never been able to start on mag. Do I have to "spin" it to start on mag, or will a quarter turn still start it? I have three T's with strong mags, so should be able to start on mag, but never have.
To crank start on mag the only difference is to advance the spark lever about 3-4 notches. Same 1/4 flip of the crank as if starting on bat.
Not all cranks are original, and certainly not the long one from another car I cut down to clear the windsplitter radiator on the Speedster.
What is the usual position of the crank at Top Dead Center of the pistons? Is it at 3, 6, 9 and 12 o'clock, or some other angle? Mine is at those positions.
I engage the crank at 5-6 o'clock, and pull up, hitting TDC at 9 o'clock - with the LEFT hand. Since the Fronty has pretty good compression, I do not attempt to crank at any other angle. Pulling up through 9 o'clock with my right hand on the radiator gives me good leverage.
Pulling across to a 12 o'clock TDC would be more difficult until you developed those muscles, probably by doing more than just cranking the engine.
So are you saying that you engage the crank with the left hand, pull to 9 o'clock, then change hands, and pull further with the right hand? Dave
Hmmm, did I say that, Dave? I pull the crank to just past 9 o'clock, then the compression takes over and I let go the crank.
No, I guess I read that wrong...bad eyes? Old age? Reading before morning coffee? Dunno. Thanks. Dave
I think what Ralph's saying is he holds onto the radiator with his right hand to keep from falling on his posterior while cranking with his left hand.
My left arm is weak due a bad break when I was 15, so I have to crank with my right arm. The natural tendency is to grab the handle with the thumb over, Victrolas, music boxes, apple peelers & screwdrivers don't kick. It's a mind set to remember to keep the palm open with the thumb down.
Sometimes you should take things at face value. If everyone gives you advise from collective experience, maybe you should take it. You should make up your own mind, experiment, change and learn for your self. I had an A for my first car in the 50's and drove it thru hi school in New England, then to Calif. (on Rt 66). I was told the same thing about pulling up from 8 - 12 (approx.) and the thumb and fingers on the same side. When a battery is too expensive, you learn to crank even at 30 below in Vermont. T's and A's seem similar to start with mixture and timing. Maybe just luckey but no broken bones yet. The 26 I have now doesn't seem as easy to start though. Could be just getting older?