A Gas Engine Magazine reader shares his gas engine tips.
Introduction to Following Story I'm sending you the enclosed material to do as you like with. Some of it may seem old hat to you or many of the readers, however I've been surprised at the number of people (many of them garagemen) who did not know some of these simple things. Maybe you will have better articles on these subjects (Then good, maybe I'll learn something) Though I've had years of experience with engines, the number of makes has been rather limited. I'm not claiming to be an expert by any means, but have found all directions given in these articles to be as true as the day is long, and these gas engine tips might be of help to some.
I like your magazine a lot and hope other readers will contribute as much.
I recall back in the days before the self starter became universal on automobiles of seeing people now and then going around with their right arm in a sling. When questioned as to what had happened the answer was almost always that their car had kicked them when they tried to start it. Some were lucky enough to survive with merely a sprained wrist, but cranking a car was considered rather dangerous. When I was a Boy Scout, longer ago than I like to admit, I passed an examination for a merit badge in automobiling. One of the things I learned was how to grasp the crank. They said to take hold of it with the thumb on the same side as your fingers are on, that is, do not reach clear around the crank with your hand. Also do not try to spin the motor, but instead give it a series of upward jerks, do not bear down on it, if you do, you are more likely to be injured in case it kicks back. I think that was very good advice.
My dad bought his first car (A Model T Ford without self starter) in 1916. One of the first things he did was to hook up 4 dry cells in series and connect them to the extra post on the back of coil box, then by turning the switch key to the left the coils became energized from the batteries. He temporarily removed the wires from the spark plugs. Then he set the No. 1 cylinder on top dead center and bent the control rod to the timer slightly, so when the spark lever was raised clear up it would fire just after dead center. He knew then that if the spark lever was raised clear up when cranking that there was no danger of being kicked. He and I drove that Ford more than 10 years after that, always starting it by arm strong method and we were never kicked by it.
Ford was turning out Model T's by mass production in those days and apparently paid very little attention to proper setting of spark. (At least that was the way it was with this particular one.) Also I suspect some of the owners did not understand just what retarding the spark meant. Some of the accessory mail order companies sold a ratchet affair which when bolted to the crank made it impossible for the engine to turn backward. I think that was a very good idea. Another gadget had a handle extending through the floor boards, and by pulling on it the motor could be turned a quarter turn at a time. (similar to the recoil starters on modern lawn mowers.) I never saw but one of these, and the owner said it worked fine except in cold weather, then it was best to go back to the crank. I never have heard of anyone being injured starting a John Deere tractor with their flywheel starting. You could always let go of the flywheel if it kicked back. The Rumely Oil Pulls in the middle 20's and later had an eccentric shaped cam which could be engaged with the flywheel to prevent their kicking back. The old McCormick-Deering impulse starter that you had to set by hand was also very reliable, providing you didn't forget to set it. The automatic impulse starters made since were ok if kept clean (Free from gum and flush them out with kerosene occasionally.) Spark advance for normal running speeds need to be 15 to 30 degrees before top dead center and on most of the older engines was manually controlled.
I thought this was an unusual engine. It is a Fuller Johnson pump jack. The engine fires counterclockwise. Its owner lives in Alberta, Canada. I'm sure some of the readers would enjoy eyeballing it, as I have.
More than 30 years ago, on a road building job the boss took the magneto off a Cleveland (caterpillar type) tractor to have it repaired. He made center punch marks on the coupling so as to be sure to get it back together right. The repaired magneto gave a good spark but no amount of cranking would start the motor. He belted it up to another tractor, so as to spin it fast, and on choking it, it would only spit fire out the exhaust, making a lot of noise, but would not continue to run. He was going to take the magneto back to the garage-man who worked on it. I told him I could make it run, and he finally said to go ahead. I took the coupling apart and turned it exactly one turn ahead, lining up the punch marks again, he said that wouldn't make any difference, it was set same as before. I told him to try it now and see if it made any difference, so he did and it started easily by cranking and ran perfectly. He couldn't understand what I did and seemed to think I was practicing some sort of magic. What he didn't know was that the distributor was geared to the armature shaft and only ran half as fast and the way he had it set, though the armature and breaker point setting was ok, the distributor was out of time the way he had it set and was sending the spark to the wrong cylinders. (It was 180 degrees out of time). The distributor ran half as fast as the armature and rotated in the opposite direction.
At a County Fair, come evening, the dealer took all the spark plug wiring off his Allis-Chalmers tractors that he was displaying, so no vandals could start them up during the night. The next morning when he put them back on he couldn't start them either. He couldn't seem to figure out how to get them back right, and of course couldn't run the tractors. It was very simple, I knew the firing order of the motors (1-3-4-2) and by removing the No. 1 spark plug of each one, holding my thumb over the hole to detect the compression stroke, then screwing spark plug back in cylinder head, connected it to the proper terminal of magneto, (Remembering that the distributor rotated in opposite direction to the armature) connected remaining wires in proper sequence (1-3-4-2) and soon had all five of his tractors running. I'm not telling this to brag, but to instruct and hope I've made myself clear as to what I did.
We bought a used McCormick-Deering 10-20 years ago. When this tractor was running full speed or pulling it ran ok, but when idling it would fire on only 3 cylinders, with the No. 2 cylinder always missing. That sounds simple and easy to fix, but it didn't turn out that way. Compression was good, and even, on all cylinders, new spark plugs were tried, spark was good on No. 2 cylinder, nevertheless dealer took magneto in and had it thoroughly checked and brought it back with new distributor head, but motor still ran same as before. Firing sequence was checked and found to be ok. No crossed ignition wires. Valve clearance checked and found to be ok. Head was removed, no water in cylinders, new head gasket installed. Entire manifold and carburetor assembly removed and dis-assembled, nothing found wrong, re-assembled and put back on with all new gaskets, motor still ran same as before. Dealer was stumped, never had one act like that before. He sent into Jackson for company service man who came out and worked on it for a couple of hours. Dinner was then ready so he quit for time being. After hearty meal and a cigar he went back to work on it. With motor idling he stuck a screwdriver between coils of valve springs, twisting it so as to increase tension and when he got to No. 2 cylinder and so increased tension on exhaust valve spring Presto! the cylinder fired perfectly. The spring had lost it's tension, and when the motor was idling the intake manifold vacuum was high, which sucked the exhaust valve open, leaning up the mixture on that cylinder sufficiently to make it quit firing. This might happen on any motor and if you should have similar trouble that would be one possible place to look for the trouble.
Winding just coming into view here as igniter points trip open. If provision is made for spark retard when starting, it should be retarded.
If you find it necessary to re-time the valves on an engine and there are no punch marks on timing gears, Here's my method. Put the piston on top dead center, (Or in cylinder as far as it will go) Now turn the large timing gear in its normal direction of rotation till the exhaust valve will have just closed, then mesh the gears. If intake valve is mechanically operated same as exhaust valve it will be just ready to open. Some of the higher speed engines have a bit of overlap here but not enough to change timing as much as one tooth on gears. If intake valve is suction operated pay no attention to it, as it will open automatically on following outward stroke of piston. This system of timing has worked 100% for me and can be used not only on Flywheel engines but on tractors and automobiles as well. On multi-cylinder engines pick any one cylinder and follow through.
Setting the rotary magneto properly on engines with make and break ignition, John Deere, United etc. (Low tension system). Igniter should trip (and points open) when armature is at position shown in illustration. This setting may seem a bit late to some, but is necessary because of what is called Armature Reaction.
A load of flywheels taken at the first show, 1964, of Roy Magnuson and Carl Fredrichs at Emerson, Nebraska.
This is my Fordson tractor which is used every year on a 22 inch threshing machine.
Here is a picture of my 25-50 Avery Tractor.